Zeitschriften und Ausgaben

Volumen 26 (2019): Heft 4 (December 2019)

Volumen 26 (2019): Heft 3 (September 2019)

Volumen 26 (2019): Heft 2 (June 2019)

Volumen 26 (2019): Heft 1 (March 2019)

Volumen 25 (2018): Heft 4 (December 2018)

Volumen 25 (2018): Heft 3 (September 2018)

Volumen 25 (2018): Heft 2 (June 2018)

Volumen 25 (2018): Heft 1 (March 2018)

Volumen 24 (2017): Heft 4 (December 2017)

Volumen 24 (2017): Heft 3 (September 2017)

Volumen 24 (2017): Heft 2 (June 2017)

Volumen 24 (2017): Heft 1 (March 2017)

Zeitschriftendaten
Format
Zeitschrift
eISSN
2354-0133
Erstveröffentlichung
20 Dec 2019
Erscheinungsweise
4 Hefte pro Jahr
Sprachen
Englisch

Suche

Volumen 25 (2018): Heft 1 (March 2018)

Zeitschriftendaten
Format
Zeitschrift
eISSN
2354-0133
Erstveröffentlichung
20 Dec 2019
Erscheinungsweise
4 Hefte pro Jahr
Sprachen
Englisch

Suche

55 Artikel
Uneingeschränkter Zugang

Properties of the Baltic Crude Oil in the Oil-in-Water Emulsion Form: Excitation-Emission Spectra

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 7 - 14

Zusammenfassung

Abstract

Due to the fact that marine environment contamination by oil substances are not uncommon, it is necessary to improve the ability of determine their origin. Therefore, research on the possibility of recognizing the type of oil using its individual characteristic manifested in the processes of fluorescence excitation has been undertaken. Oil pollutants present in seawater mainly coming from ship drives, tankers, pipelines or sea bottom seeps, moreover oil leaks from offshore extraction equipment also are possible. For this reason, the crude oil extracted from the Baltic Sea deposit in the Polish Maritime Areas has been chosen for tests. Fluorescence properties of water containing small amounts of oil (concentrations from 5.59 to 55.4 ppm) in the form of oil-in-water emulsion were tested. Individual samples were assigned matrices of fluorescent values for different wavelengths, while excited by monochromatic light also for different wavelengths. The obtained matrices were visualized as a contour maps and 3D charts. For considered concentrations of crude oil dispersed in water, the wavelength-independent fluorescence maximum was determined. Obtained result indicates that in the studied wavelength range, the total fluorescence intensity is proportional to the oil concentration only for the lowest oil concentrations. The analysis of the objective parameter of the difference between the shapes of spectra indicates the similarity of the spectral shape for the lowest oil concentrations. These results are the methodological suggestion, that for the purpose of identifying the type of oil dispersed in water, spectra should be determined for sequences of different dilutions, until the excitation-emission spectra shapes become independent from the oil concentration.

Schlüsselwörter

  • crude oil
  • excitation-emission spectra
  • fluorescence
  • seawater
Uneingeschränkter Zugang

Applications of Metallic Composites in the Automotive Industry and their Machining by the EDM

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 15 - 23

Zusammenfassung

Abstract

The article deals with the problems of application of aluminium matrix composites in car industry and electro discharge machining (EDM) of selected composites, which are used for engine pistons.

Composites with Al+20%Si+3%Cu+1%Mg matrix were manufacturing by the powder metallurgy route in the process of cold compaction, degassing and hot extrusion. As the reinforcing phase Al2O3 particles with average size of 3, 9, 23 and 53 μm were used. Samples had constant reinforcing phase 5 and 10 % by volume. Electro discharge machining was performed using machine equipped with RLC generator. Four modes of energy of single discharge Ei in the range of 0.165 to 2.268 mJ were applied. EDM was carried out in a free – system. The main parameters determined after machining were volumetric productivity Vw (mm3/min) and roughness of the machined surface expressed as Ra. It was shown that energy of single discharge influence mainly on the EDM process running. The higher was Ei, the higher were value of Vw. Increasing particle granularity from 3 to 53 μm caused decreasing in process productivity 13 to 19%. Ei affects the surface roughness during EDM. The value of Ra increases as this energy increases. When the size of reinforcing particles is growing, roughness parameter Ra is also growing.

Schlüsselwörter

  • aluminium matrix composites
  • automotive industry
  • electro discharge machining
  • EDM productivity
  • surface roughness
Uneingeschränkter Zugang

Concept of an Expert Diagnostic System of the Turbine Engine’s Flow Path Elements

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 25 - 32

Zusammenfassung

Abstract

The article presents a concept of an expert diagnostic system of the turbine engine’s flow path (compressor – combustion chamber – turbine) elements. The system adopts diagnostic signals obtained with the use of non-destructive methods implemented on the non-operating engine. The aim is to detect and assess early stages of damage to selected elements of the engine. The achievement of a reliable diagnosis on the condition of the elements requires the application of a set of diagnostic methods and carrying out the inference, including knowledge about the degradation processes of elements and correlation of the diagnostic (signals) tests results obtained with various methods. A convenient tool, which supports solution of such a set problem is an expert system, which on the one hand, makes it possible to organise the existing formal knowledge, and on the other hand – to use non-formal, or even uncertain, knowledge. The presented concept of the expert diagnostic system is based on PC-Shell system of AITECH Polish Company.

Schlüsselwörter

  • engine
  • diagnostics
  • expert system
  • knowledge base
Uneingeschränkter Zugang

New Methods of Marine Power Plant Diagnostics

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 33 - 39

Zusammenfassung

Abstract

Up-to-date, of high-tech design techniques of machine operation require constant monitoring on some levels. Generally, the monitoring today is limited to failure detection and machinery components check.

The Marine Engineering Faculty of Gdynia Maritime University designed the System for Marine Engine Operation Assistance on the basis of Sulzer Diesel AL 25/30 testing station.

The engine modernization and wider research and survey capabilities resulted in engine operation quality improvement, marine power plant research enhancement. The project broadens the research range and engine failure expertise as well as takes into consideration innovative marine fuel emissions. The goal has been achieved in the way of the test equipment modernization including: effective pressure sensors, high pressure fuel sensors, monitoring and visualization of the engine systems’ parameters, electronic indictors adopted to continuous operation at all cylinders in the same time, and high class decision aid computer equipment. Engine modernization and data base extension allow for carrying out a wide scope of research.

Additionally, the article presents innovative diagnostic solutions together with their applications.

Schlüsselwörter

  • diesel engine
  • diagnostics
  • roughness
  • surface
Uneingeschränkter Zugang

Influence of Flame Heating Parameters on the Hardness of Hardened C45 Steel

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 41 - 47

Zusammenfassung

Abstract

In this article, the impact of selected parameters of heating using a gas torch on the hardness of hardened alloy steels C45 was presented. The staff of the ship’s engine room sometimes uses flame hardening during casual repairs of the machines weared as a result of operational extortions. The purpose of emergency repairs is to restore the possibility of work of ship machinery and equipment for the duration of the vessel’s journey. An acetylene-oxygen torch was used to heat the steel. As the analysed parameters of the technological process, the heating time and the distance between the nozzle and the workpiece were selected. The values of the mentioned parameters have been selected so that the temperature of hardened steel is in the range from 800 to 1250 °C. The following values of the adopted machining parameters were used: the heating time was 60, 85 and 110 seconds, while the distance of the torch nozzle was 10, 20 and 30 mm. After heating, the samples were cooled by immersing in water. The research was based on a randomized orthogonal experiment plan. The purpose of the quantitative assessment of the influence of heating parameters on the hardness of hardened C45 steel, done statistical analysis variance analysis, multiple regression and mathematical optimization by the Tagichi method. Conducted tests and statistical analysis showed a significant effect of selected parameters of flame heating on the hardness of hardened C45 steel. The greatest influence on the hardness of the steel is the distance between the nozzle and the workpiece. The highest value of hardness was obtained using the following parameters of flame hardening: nozzle distance 30 mm, heating time 60 seconds.

Schlüsselwörter

  • hardening
  • flame heating
  • multiple regression
  • mathematical optimization
  • Taguchi method
Uneingeschränkter Zugang

The Issue of Energy Management in Walking Machines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 49 - 57

Zusammenfassung

Abstract

The energy management is a serious issue in the platforms of mobile robots, and especially walking robots. The solutions are sought so as to obtain the furthest possible range with the energy resources at the disposal. Properly adjusted configuration of the drives and the manner of energy management has a key impact on effectiveness of the drives. The article presents the most important features of the basic driving systems, possible configurations, and steering manners along with the assessment of their effectiveness. The article will present classical and hybrid drives. The authors present a sample analysis of energy “costs” of steering for the selected systems. The analysis will be supported with results of the simulation performed with the use of constructed computer models.

The guidelines for designing of the systems for walking platforms will be proposed, enabling to obtain high dynamics and energy efficiency of the system.

Schlüsselwörter

  • drive of a walking machine
  • energy costs in a mobile machine
  • linear load-sensing systems
Uneingeschränkter Zugang

Concept and Model of Terrain Wheeled Tractor with Hybrid Drive

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 59 - 65

Zusammenfassung

Abstract

The article presents construction concept of a tractor with hybrid, diesel-hydraulic and diesel-electric drive meant for the use in livestock holdings. The tractor is enabled to cover short distances with the combustion engine switched off. This solution uses independent engines to propel front and rear axles. This article presents a computer model and simulation results for the project of a hybrid, diesel-electric tractor based on a benchmark machine Fendt 516.

Aside from the ability to drive with diesel engine switched off, the proposed solution has additional positive features allowing smooth transition of relation of peripheral speed of the front and rear wheels. It enables to obtain higher tractive powers for various conditions in a broader range than for a traditional solution (with propelling both axles with one engine through different transmission systems and specific difference of peripheral speed of the wheels). The computer model was built on the basis of the benchmark machine.

Schlüsselwörter

  • terrain wheeled tractor
  • hybrid drive
  • computer model of a tractor
Uneingeschränkter Zugang

Diagnostic Aspects of a Crankshaft Torsional Oscillations Monitoring by IAS Measurement

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 67 - 74

Zusammenfassung

Abstract

Continuous monitoring of diesel engine performance under its operating is critical for prediction of malfunction development and subsequently functional failure detection. Analysis of Instantaneous Angular Speed (IAS) of the crankshaft is considered as one of non-intrusive and effective method of detection of combustion quality deterioration. The article contains presentation of attempt of monitoring of piston engine’s crankshaft torsional vibrations by measurement of Instantaneous Angular Speed at free, and power output ends of the engine’s crankshaft. The angular speed measurements was done using two optical sensors for reading the IAS, mounted at shaft line’s opposite ends, one at free end of the crankshaft and second at end of generator’s shaft. In the article is presented description of the measurement system and explanation of its mode of work. Experiments were based at two kinds of malfunction possible to be simulated at test bed. First one was simulation of a leak of fuel injection pump, the second one relayed on mounting of sets of injection valves with different nozzles characteristics (spraying nozzle angle), giving different parameters of fuel injection. Presented results of experiment derives from test cycle carried out using laboratory stand of Gdynia Maritime University equipped with 3- cylinder self – ignition engine, powering electric generator.

Schlüsselwörter

  • diagnostics
  • diesel engine
  • torsional vibrations
  • torque and angular speed
Uneingeschränkter Zugang

The Effect of Parameters Burnishing Rolling – Pressuring Process in Aspect to Technological Quality Surface Layer of 316L Stainless Steel

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 75 - 81

Zusammenfassung

Abstract

In the manufacturing of machine elements was important to technological quality products. In surface engineering one of the economic and ecological treatments used for technological properties were burnishing rolling – pressuring process. This is a surface plastic forming a local plastic deformation based on the overall impression given by smooth and hard tool. In production, engineering cylindrical outer surfaces (e.g. plugs propulsion shaft centrifugal pumps seawater) were finishing. You can therefore propose burnishing in exchange for abrasive machining.

The article presents the influence of parameters for burnishing rolling – pressuring process on the degree of relative strain hardening and surface roughness reduction ratio. Burnishing process carried out for 316L stainless steels. After the experimental study, it was determined that there was an increase in hardness and a decrease in roughness of the top outer cylindrical layer of stainless steel, which can be applied to the centrifugal pump shafts ship. Important question to determine in the article of the research was to receive appropriate technological quality. The burnishing due the technological and economic aspect in the production of machine parts in exchange for the abrasive processing can be used. After the experiments, it was found that the technical parameters are influenced by the hardness and the roughness of the outer cylindrical surfaces and the material ratio curve a convex shaped, which, taking into account the load capacity of the surface will be directly affected by its resistance to wear and corrosion of the surface layer.

Schlüsselwörter

  • burnishing process
  • hardness
  • roughness
  • surface layer
  • stainless steel
Uneingeschränkter Zugang

Performance Characteristics of Panel Filters for Internal Combustion Engine Inlet Air Working in a Two-Stage Configuration

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 83 - 94

Zusammenfassung

Abstract

Air filtration conditions in a single-stage and a two-stage filtration system (multicyclone-porous panel filter) are presented. Allowable flow resistance ∆ pfdop values reducing the air filter service life are specified. The benefits of using a multicyclone as a first stage of air filtration, including improved mobility and extended service life, are discussed. Criteria for selecting the filter media for the automobile air intake system using an absorption coefficient of dust km determined at a specific allowable flow resistance ∆pfdop are specified. New methods and conditions to determine the absorption coefficient of dust km for article filter and non-woven fabric filter in a single-stage and a two-stage filtration system are developed and presented. The separation efficiency and separation performance as well as the flow resistance characteristics of the filter set including a single cyclone and a filter element with a specially selected filter medium surface area are tested. Absorption coefficients of dust km for the tested paper filter and non-woven fabric filter were determined for an allowable flow resistance. The effects of dust particle size distribution in the air downstream of the cyclone on reducing the absorption coefficient of dust of the paper filter and non-woven fabric filter in a two-stage filtration system are shown.

Schlüsselwörter

  • two-stage air filter
  • filter medium
  • separation efficiency
  • flow resistance
  • absorption coefficient of dust
Uneingeschränkter Zugang

Monitoring of Rapeseed Oil Fuelled Agricultural Machinery

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 95 - 100

Zusammenfassung

Abstract

Pure plant oil fuels, used in compatible agricultural machinery contribute to sustainable food supply. Especially rapeseed oil fuel significantly reduces greenhouse gas emissions up to 91 % and thus, lowers the carbon footprint of agricultural products. However, despite this advantage plant oil fuels are barely used in practice, because of technical, economical and sustainability concerns of potential users. It is the purpose of this work, to show the reliability, downtimes and the emission behaviour of pure rapeseed oil compatible tractors in practice. As test fuel, cold-pressed rapeseed oil fuel, complying with the national German standard DIN 51605 was used. Emission testing on the tractor test stand is based on the standard procedure of EU guideline 2016/1628. Differing from type approvals, where engine test stands are used, here the measurement is done at the tractors with mounted engines. The power is measured at the power take-off (PTO) with a dynamometer. As testing cycle, the Non-Road-Steady-Cycle (NRSC) and an adapted Non-Road-Transient-Cycle (10sNRTC) are applied. For real driving emission (RDE) measurements, two state-of-the-art tractors are being used. By using a PEMS Semtech Ecostar, which was set up in a box for off-road use, the emission components CO, HC, NOX are measured. Investigation of the monitored 20 tractors (exhaust stages I, II, IIIA, IIIB and IV) for more than 60.000 hours, showed no considerable failures or damages. Generally, the limited exhaust gas components (NOX, CO, HC, PM) determined at a tractor test stand remained nearly at the same level over the operating time. Plant oil tractors with exhaust gas stage IV achieve the legal emission limits with rapeseed oil fuel during both, the NRSC and 10sNRTC. Results of RDE measurements also show that recorded emission values are within expected limiting values for both fuels. Conformity factors that relate actual emissions, measured with PEMS, to corresponding test cycle values, measured at the test stand are within approaching legitimacy.

Schlüsselwörter

  • greenhouse gas emissions
  • liquid biofuel
  • pollution
  • environmental protection
Uneingeschränkter Zugang

The Effect of Adding 2-Ethylhexanol to Jet Fuel on the Performance and Combustion Characteristics of a Miniature Turbojet Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 101 - 109

Zusammenfassung

Abstract

There are currently many studies undergoing in the field of using alternative fuels for supplying different types of propulsion units. The ASTM standard in the aerospace industry, allows using five different technologies of manufacturing synthetic components apart from standard oil-based fuel for the propulsion of turbine engines (as a blend up to 50% with conventional fuel). One of these is a technology associated with the process of converting alcohols (isobutanol) to jet fuel – Alcohol to Jet (ATJ). In the research performance, emission parameters were measured on laboratory test rig with miniature turbojet engine (MiniJETRig). The test rig has been created in Air Force Institute of Technology for research and development works aimed at alternative fuels for aviation. The miniature engine was fuelled with conventional jet fuel – Jet A-1 and blend of Jet A-1 with 2-ethylhexanol. The results for this blend were compared with the results obtained for neat Jet A-1 fuel in terms of different engine operating modes, according to specified methodology. The conducted tests did not show significant differences in engine operating parameters (thrust, fuel consumption and thrust specific fuel consumption) and the values of CO, CO2 and NOx emission indices between the tested fuels. The engine tests took place in similar ambient conditions. Laboratory tests of selected physicochemical properties were also carried out for both fuel samples.

Schlüsselwörter

  • alternative fuels
  • alcohol to jet
  • combustion process
  • miniature jet engine
  • exhaust emission
Uneingeschränkter Zugang

A Concept of the Automatization of Dangerous Driving Manoeuvres

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 111 - 122

Zusammenfassung

Abstract

Automatic control is one of the main characteristic features of the present-day “electrified” motor vehicle. The avoidance of a suddenly appearing obstacle, including a rapid lane-change manoeuvre, is counted among the driving manoeuvres that are most dangerous and difficult to be automatized. Note that this seems to be a fundamental problem for autonomous cars. The authors have shown general vehicle automatization concepts derived from the control systems theory. Against this background, they have presented results of their own analytical studies and simulation research related to the system of automatic controlling of a rapid lane-change manoeuvre. A controller algorithm developed within this work, where a simplified reference model of the lateral dynamics of a motor vehicle was used (transmittance-type model based on well known “bicycle model” but transformed and linearized), was successfully examined in exhaustive simulation tests. The virtual object used for the simulation tests was an extensive simulation model (3D, nonlinear, MBS type) of a two-axle motor truck of medium load capacity, driven with quite a high speed. This detail model had been experimentally verified. In the article, only a fragment of a large research project has been described.

Schlüsselwörter

  • motor vehicle
  • active safety
  • lateral dynamics
  • avoidance automatization
  • obstacle voidance
  • model tests
  • simulation tests
Uneingeschränkter Zugang

Problematics of Modelling Systems for Technical Service of Means of Transport

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 123 - 133

Zusammenfassung

Abstract

Exploitation of means of transport is an important decision issue for transport companies that perform transport tasks. The means of transport during their operation lose their functional properties, which mean that they require technical service and repairs. The components of operating costs of means of transport are expenditures incurred for servicing and expenditures incurred for repairs. As the first cost component increases, the other will decrease and vice versa. We obtain the optimal economic effect of the means of transport when the sum of costs reaches the minimum value. The article presents the problems of optimization of the technical service system. This required identification of technical services and basic parameters characterizing the operation system. On this basis, a mathematical approach to the problem of modelling the maintenance system is presented, including the decision variables, constraints and the criterion function. The identification of the problem of modelling the technical service system is presented in the case study for modelling the technical service of means of transport – buses in the company providing passenger transport services in public transport.

Schlüsselwörter

  • technical service
  • technical service system
  • modelling
Uneingeschränkter Zugang

Expert System Application for Improving the Manufacturing Process for Recreational Watercrafts Modelling Yacht Propulsion

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 135 - 142

Zusammenfassung

Abstract

This article deals with the problems of design improvement and the process of production preparation for recreational watercrafts. An original expert system was created to facilitate the design of mechanical equipment systems and to support the production of pleasure boats. This expert system contains information about issues related to the selection of appropriate mechanical equipment used in modern yachts. An expert system is a computer program, which contains information about a specific and usually narrow field of expertise. With the help of this kind of program, it is possible to solve problems on the same level as a human expert. Like most expert systems, this program is built in such a way that the knowledge base is separated from the rest of the system. It contains two main modules: the knowledge base and the inference mechanism. This system provides conclusions in a descriptive form and in the form of numbers, and presents explanations, diagrams, drawings, photos and videos. What is unique about this expert system is that a user with specialist knowledge in the field of yacht engineering can easily modify the knowledge base. With the development of technology, it is easy to feed new information into the system. This system can become a major tool in design offices and plants producing yachts, because it can be easily expanded and adapted to individual needs.

Schlüsselwörter

  • expert systems
  • yacht propulsion
  • manufacturing of yachts
  • knowledge engineering
Uneingeschränkter Zugang

Conversion of Energy in Electric Drive Supported by the Hydrostatic Drive

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 143 - 150

Zusammenfassung

Abstract

In the article, a study of conversion of energy in a hybrid (electro-hydrostatic) drive of a utility van intended for city traffic is described. In this hybrid drive, the electric drive is periodically accompanied by hydrostatic drive, especially during acceleration and regenerative braking of the vehicle. We present a mathematical model of the hybrid drive as a set of dynamics and regulation equations of the van traveling at a given speed. On this basis, we construct a computer program, which we use to simulate the processes of energy conversion in electro-hydrostatic hybrid drive. The main goal of the numerical simulation is to assess the possibility of reducing energy intensity of the electric drive through such a support of the hydrostatic drive. Our results indicate that it is possible to significantly increase the efficiency of energy conversion in the electric drive by support of the hydrostatic drive. In the article, chosen results of simulation studies for multiple starting and braking the car are given, and they show a 30% decrease for energy drawn by the hybrid drive, compared to solely electric drive.

Schlüsselwörter

  • numerical simulations
  • hybrid drive
  • electric drive
  • hydrostatic drive
  • energy conversion
  • city traffic
Uneingeschränkter Zugang

Selected Aspects of Costs Shaping in the Intermodal Terminal

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 151 - 158

Zusammenfassung

Abstract

The article presents the problems of designing intermodal terminals from the point of view of expenditures on construction and equipment as well as costs of its operation. The scope of factors to be considered at the design stage of the intermodal terminal was determined. The principles of calculation of expenditure on terminal infrastructure are presented. Based on these expenditures, the principles of calculating the cost of maintenance of equipment and labour are outlined. In addition, the practical examples of determining the cost of operation of handling equipment and labour costs are presented. The terminal carries out the functions of transhipment of intermodal transport units between means of transport, belonging to different modes of transport and the operations on these units in connection with their storage. Due to the different types of external means of transport operated in the intermodal terminal, a sufficient number of rail tracks, roads lines, storage, and handling areas should be provided. Apart from expenditures and costs, an important element in the design of an intermodal terminal is its location in the logistics network.

Schlüsselwörter

  • intermodal terminal
  • container
  • TEU
  • costs
Uneingeschränkter Zugang

Energy Consumption Estimation of Non-Pneumatic Tire and Pneumatic Tire During Rolling

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 159 - 168

Zusammenfassung

Abstract

The characteristics of the car tire, and especially its deformation and interaction road, are mainly factors affected the energy consumption of the vehicle and consequently the amount of fuel consumption and emissions to the environment the harmful exhaust gas components. It is estimated that approximately 80-90% of the total energy losses (rolling resistance) are due to internal tire friction, which occurs during its deformation, the remaining 10-20% are ventilation losses, tread face interaction with the road surface and cyclical compression and expansion of air enclosed in the tire. Non-pneumatic tires (NPT) (as a direction of development) are the alternative solutions for conventional tires. Their advantages are as follows maintenance-free and the resistance to typical for pneumatic tires mechanical damages can be a major cause of their widespread use in future (and thus electric) cars. In the available publications, the results of the estimation of the features NPT based on numerical simulations are only presented. There is lack of experimental research results concerning real objects, which determine their driving properties.

Presented work is an attempt to check how the change in wheel structure affects the energy consumption of rolling wheels. Research objects (non-pneumatic tire and pneumatic tire) were selected for the size and destination compatibility. Experimental research were carried out at a universal quasi-static tire testing station, which is located at the Institute of Mechanical Vehicles and Transport at the Department of Mechanical at the Military University of Technology. According to the authors, the obtained results can be an interesting and unique supplement to the problem of assessing the properties of new and future (non-pneumatic tire) construction of vehicle wheels.

Schlüsselwörter

  • non-pneumatic tire (NPT)
  • airless tire
  • resilient tire
  • pneumatic tire
  • special wheel
  • rolling resistance
  • energy consumption during rolling
Uneingeschränkter Zugang

Methods for Determining the Take-off Speed of Launchers for Unmanned Aerial Vehicles

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 169 - 176

Zusammenfassung

Abstract

Unmanned aerial vehicles (UAV) are currently a very rapidly developing type of aviation. The problem of support during the take-off with the use of, i.e. take-off launchers arose along with their development, especially for UAVs with weights and dimensions preventing manual take-off. One of the major issues associated with UAV take-off launchers is for its UAV accelerating element to obtain its initial speed. The article presents three methods of determining launcher take-off speeds for unmanned aerial vehicles, i.e. the concentrated very oblique projection method, the high-speed camera methods, and the acceleration recorder method. The take-off launcher carriage speed in the oblique projection method is determined from a formula. This method involves “ejections” of concentrated masses from the UAV mass range and measuring the component values resulting from the used formula, which contains the range of the oblique projection, the elevation of the projection and its angle. The method using the high-speed camera involves recording the course of ejections of the concentrated mass from the launcher. The average take-off speed is determined on the basis of a take-off run length (section of the launcher race, where the unit accelerates) and defining the start and end frame of the carriage movement. The third method for the determination of the take-off speed utilizes an acceleration recorder. The method with the recorder involves registering a change in the accelerations when the take-off carriage is being accelerated by a system fixed on the carriage or the accelerated object. The article presents the methodology of dynamic tests of object acceleration on a launcher, necessary for the determination of speed with the mentioned methods. Selected results from actual tests with the use of the 01/WS/2015 launcher, which is an element of the ZOCP JET2 set, were presented. The test results are presented in a tabular form. The methods for the determination of the take-off speed were compared on the basis of performed tests. Based on the obtained results, the factors impacting the accuracy of each of the methods were identified.

Schlüsselwörter

  • aviation
  • unmanned aerial vehicle
  • take-off launcher
  • take-off speed
  • acceleration recorder
Uneingeschränkter Zugang

Fatigue Strength Analysis of Welded Aluminium Stairs

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 177 - 184

Zusammenfassung

Abstract

The article presents numerical analyses and results of experimental fatigue tests of the welded stairs made from prefabricated EN-AW 6063-T66 aluminium alloy thin-walled profiles. Fatigue life analysis of welded thin-walled structures is a complicated and demanding task. Fatigue analysis of stairs was carried out according to the concept of a weak link, which was verified experimentally. The FEM method was applied in strength analysis. The conducted research allowed identifying the weak link of the structure at the welded joint. The samples stairs were subjected to fatigue tests. The fatigue tests have been conducted using specially designed set up. The experiments confirmed the numerical analysis. The cracks occurred at welded joints before expected fatigue life to fracture. Then the stairs structure was modified by changing the weld joints arrangement. The fatigue tests were carried out again and showed further weaknesses of their structure cracking of the step profile. To precisely capture this problem, detail finite element calculations for the analysed stairs have been conducted. Applying the nominal stress method, this problem was solved changing the treads profile of the stairs step. The last improvement in the construction was sufficient to satisfy fatigue strength requirement of the analysed structure. The weak link approach and nominal stress method proved to be an effective tool in fatigue analysis of the examined structure.

Schlüsselwörter

  • fatigue tests
  • welded joints
  • aluminium thin-walled constructions
Uneingeschränkter Zugang

Analysis of Possibilities of Increasing a Turbulence by Throttled Axisymmetric Stream for a Fluid Flow Inside Closed Duct

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 185 - 190

Zusammenfassung

Abstract

Fluid flow through the closed duct is a common phenomenon, which is used in many technical applications. A stream of a fluid is often disturbed by different shapes of elements, which have an effect for a flow and causes the growth of a turbulence. Turbulence rising causes an increase of heat transfer process and eliminates areas of flow stagnation in thermal devices. Article presents methodology and results of research about possibilities of turbulence increasing for a fluid flow inside a closed duct. Authors analysed capabilities of application of an internal stream of a fluid in the axis of the tested duct, in the inlet to analysed construction for mainstream turbulence expanding. An additional stream of a fluid was added into the model by internal, partially throttled pipe, which was clogged by special disc. Contact between the disc and internal pipe generated a small gap, where an additional stream of a fluid was directed. Numerical analysis of a level of turbulence for a fluid flow through analysed duct was realized in ANSYS Fluent environment, as an unsteady simulation with Delayed Detached Eddy Dissipation model of turbulence. Experimental research was realized with constant anemometry measurement method. Results of experimental and numerical analysis show, what part of a fluid inside duct disturbed mainstream of a flow.

Schlüsselwörter

  • closed duct
  • turbulence increasing
  • numerical calculations
  • fluent
Uneingeschränkter Zugang

Selection of Turbocharger for the T3.251 Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 191 - 196

Zusammenfassung

Abstract

In this research, a selection of turbocharger for atmospheric engine with automatic ignition T3.251 is described. This experimental engine was designed for driving small tractors. The purpose of turbocharging was to achieve a power of 45 kW. This atmospheric engine at 2250 rpm had power of 35 kW. In the first phase, the initial calculations of the turbocharger parameters were made according to the method proposed be Garret Company. The B65 turbocharger was selected for the study with flue gas exhaust in a multi-variant combination of turbines and compressors. Modifications were made to both turbine and compressor bodies as well as the size of their rotors. Altogether, eleven variants of the B-65 turbocharger were studied. The B65 turbochargers were fitted with an adjustable exhaust valve. By changing the spring preload, the supercharging pressure was adjusted. The research was carried out by performing the external characteristics and load characteristics of the engine under the same operating conditions and settings of the engine and injection equipment. The article presents the co-operation lines of an engine and superchargers using the characteristics of the discussed earlier compressors at Institute of Aviation. The effects of different turbocharger configurations on engine performance, power, fuel consumption, temperature and smoke emissions were also analysed. An analysis of the correct selection of turbochargers was performed.

Schlüsselwörter

  • transport
  • self-ignition engine
  • turbocharging
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Management of Disused Lead-Acid Batteries in the Context of the Eco-Balance Analysis

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 197 - 203

Zusammenfassung

Abstract

The article describes the results of the eco-balance analysis of the disused lead-acid batteries recycling technology. The analysis will be made using the life cycle assessment (LCA) method. The analysis was developed using the SimaPro7.3.3. software. The life cycle assessment (LCA) was made using Ecological Scarcity and IMPACT2002 + methods. The results are shown as environmental points [Pt], which reflect the potential level of environmental burdens exerted by the analysed object. The results are presented in the environmental categories, which are grouped in the impact categories. For the Ecological Scarcity method, these are emission into air, water, soil, energy, and natural resources and deposited waste. For the IMPACT2002 + method: human health, climate changes, ecosystem quality and resources consumption. The boundaries of the system under investigation include the processes of mechanical battery scrap processing, desulfurization and crystallization processes (PI), the melting processes to obtain crude lead and refining processes (PII and PIII). As the functional unit, there was accepted 1 Mg of the processed battery scrap. Particular attention was paid to the airborne emission, which adversely affect human health and climate change. The technology for which the tests were conducted offers the possibility to recover other elements, for example, secondary lead, polypropylene and sulfuric acid as crystalline sodium sulphate.

Schlüsselwörter

  • recycling
  • Life Cycle Assessment
  • environmental protection
  • lead-acid batteries
  • eco-balance
Uneingeschränkter Zugang

Evaluation of Dynamic Parameters of the Selected Components within Digitally Controlled Hydraulic System

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 205 - 214

Zusammenfassung

Abstract

Dynamic parameters characterizing proportional hydraulic components are essential factors affecting the performance of the construction machinery automatic control system. Knowledge of these parameters is inevitable in modelling the automatically controlled hydraulic power systems as well as designing and analysing the control algorithms. This article presents a methodology of assessing the dynamic parameters of selected components being part of digitally controlled hydraulic power system. The analysed system comprised a typical for mobile hydraulics applications PVG32 proportional directional control valve (DCV) and a variable displacement piston pump. The control system utilised an MC088 PLC controller with specifically prepared and configured software. The measuring system was based on CANbus, which, combined with the PLC used, allowed for flexible configuration of the sensor variables and logging both analogue and digital signals. Among others, the DCV characteristics, the response to step and sinusoidal inputs and DCV hysteresis were examined. The goal was to gather the data required for system modelling and to assess the importance and influence of the investigated parameters onto the model being created.

Schlüsselwörter

  • mobile hydraulics
  • proportional directional control valve
  • hydraulic cylinder control
  • electro-hydraulic pilot valve
  • hydraulic system modelling
Uneingeschränkter Zugang

3D Scanner Working Parameters – Influence on an Accuracy of Mechanical Vehicle Element Reproduction

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 215 - 223

Zusammenfassung

Abstract

In recent years, the reconstruction based on existing physical objects, plays an increasingly important role in research and everyday life. With the advancement of modern industry, more and more often, including automotive industry, modelling and deformation techniques of objects, based on reverse engineering, are used. One of such example is the reproduction of the geometry of motor vehicles using 3D scans. Damages of motor vehicles, cause local changes in the shape of the product and their size and character are directly related to the occurred reaction. However, to assess the damage extent and qualify the object for further repair, it is necessary thoroughly to know the condition of the object after the damage to select the appropriate technology and repair method. This is the case for reverse engineering, and 3D scanning using structural light.

The aim of the study was to evaluate the influence of the parameters of the 3D scanner on the accuracy of reconstructing the geometry of the selected vehicle element – the rear door of the Skoda Octavia in two variants, non-deformed and deformed. The dimensions of door exceeded the range of the largest measuring area of used 3D scanner, so it was necessary to use the photogrammetric technique in order to generate a point model of the object that was used to compose the individual scans.

Measurements were made with different measuring areas: 1000 × 800 × 800 mm, 500 × 400 × 400 mm and 250 × 250 × 200 mm. For the base field, 500 × 400 × 400 mm, several measurements were repeated in order to determine repeatability.

Schlüsselwörter

  • 3D scanning
  • strain identification
  • photogrammetry
  • reverse engineering
Uneingeschränkter Zugang

Experimental Analysis of Noise and Vibration of a Diesel Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 225 - 232

Zusammenfassung

Abstract

Noise and vibration of ignition compression engine is one of the most complicated fields to cope with since every mechanism that compose of the engine affect them separately. In this study, effect of diesel on engine noise and vibration has been studied on an unmodified compression ignition engine. Noise and vibration characteristic of a direct ignition engine, which was fuelled with diesel, were investigated. With the usage of equations obtained from regression analysis, estimation of engine characteristic fuelled with various biodiesels researches were carried out. Tests were conducted at fixed injection timing of diesel fuel. The first system is for diesel fuel injection; the second one is PFI (port-fuelled injection) and is used for injecting alcohol into the engine intake manifold. The engine applied to this study was a naturally aspirated, 3in-line, IVECO AIFO 8031 i06.05 diesel engine with direct injection. Experiments were conducted in a sound insulated room. For each experiment, vibration data gathered from the engine block with 3.2 kHz (for vibration) for 2 s and with 20 kHz sampling frequency for 0.320 s. All measurements were performed under conditions: angle 10; 4 different loads (4, 8, 12 and 20 kW).

Schlüsselwörter

  • biodiesel
  • compression ignition engine
  • engine vibration
  • sound pressure level
Uneingeschränkter Zugang

Maritime Radio Systems for Distress Alerting

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 233 - 240

Zusammenfassung

Abstract

The most important function of a maritime radio communication system called the Global Maritime Distress and Safety System (GMDSS) is the distress alerting function. Distress alerting is the rapid and successful reporting of a distress incident to a unit, which can provide or co-ordinate assistance. This would be a rescue co-ordination centre (RCC) or another ship in the vicinity. The article presents and evaluates the technical and operational possibilities of the maritime radio systems for a distress alerting. Especially the basic functional requirements and regulations for GMDSS referring to the maritime radio systems for distress alerting, resulting from the provisions of the International Convention for the Safety of Life at Sea (SOLAS) and Radio Regulations have been described. The article presents the role of the maritime radio systems for a distress alerting in the shipping and GMDSS as well. A current status and analysis of the systems responsible for distress alerting has been made. In this context, the operation, methods and ranges of transmitting and receiving the distress alerts by the INMARSAT system, COSPAS-SARSAT system and Digital Selective Calling (DSC) system have been described. The article also outlines the future of the maritime radio systems for a distress alerting. In this context, the two projects under the name of „E-navigation” and „The modernization of the GMDSS”, currently being implemented in the framework of the International Maritime Organization (IMO) by the Sub-Committee on Navigation, Communications and Search and Rescue (NCSR), have been presented as well.

Schlüsselwörter

  • communication systems
  • maritime distress communication
  • maritime distress alerting
Uneingeschränkter Zugang

Numerical Studies of Suspension System with Double Spring Loaded Using the Force Pulse

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 241 - 248

Zusammenfassung

Abstract

The forced vibration of a dependent rear suspension model of the two-axle vehicle, equipped with a 3D model of a double spring and a viscous shock absorber is the subject of consideration. The clearance between the master and auxiliary springs is a specificity of the double suspension construction. Dynamic analysis of such a system has been performed by forcing with different forms of force pulses using the fixed base of force 10 kN. Three different time runs (two trapezoidal and one triangular model) are used as the force impulses. Modelling and analysis taking into consideration contact problems have been developed using the MSC.Software package with a special use of Patran pre-processor and Nastran solver. A finite element method (FEM) has been used in numerical analysis of the suspension model with geometric nonlinearities, viscous damping [9] and time-varying load. The boundary conditions of numerical models correspond to a spring support in the real vehicle suspension. The non-periodic damped vibrations and damped free vibrations of the simplified suspension system are investigated during numerical analysis. Selected results of the model tests have been presented in the form of the timings of the accelerations of the spring elements and of the forces in the suspension damper.

Schlüsselwörter

  • dependent motor truck suspension
  • double multi-leaf spring
  • viscous damper
  • numerical analysis
  • FEM
Uneingeschränkter Zugang

The Influence of Changing of Cutting Parameters on Temperature and Cutting Forces During Turning Process by CCET09T302R-MF Insert

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 249 - 256

Zusammenfassung

Abstract

One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process, the technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. It is crucial to find a suitable solution which will meet the requirements as well as the work conditions of a given machine part. The article presents the results of influence of change of cutting parameters on temperature and cutting forces during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal CDS 6250 BX-1000 centre lathes. Measurement of cutting forces during turning process used DKM 2010 turning dynamometer. A cutting tool conducted the turning process with CCET09T302R-MF insert by DIJET. During the turning, the following machining parameters were used: cutting speed Vc = 226 m/min, feed f = 0.044; 0.062; 0.083; 0.106 mm/rev and cutting depth ap = 0.375; 0.625; 0.875 mm. The chemical composition of steel was measured by Solaris-ccd plus optical spectrometer. The Smartzoom 5 microscope made the view of the nose radius of cutting tool.

Schlüsselwörter

  • turning dynamometer
  • temperature and cutting forces
  • cutting parameters
  • stainless steel
Uneingeschränkter Zugang

Legal Conditions in the Aspect of Pollutant Emissions from Exhaust Systems of Rail Vehicles Engines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 257 - 264

Zusammenfassung

Abstract

One of the main objectives of the European transport policy is to increase the share of alternative modes of transport – revitalization of rail transport, promotion of water transport and development of intermodal transport, which will help to reduce the dominance of road transport. The adverse impact of transport can be felt both in the natural environment and in society, where the dynamic development of this sector has enabled significant civilization development, with the effects varying depending on the level of economic development, the degree of advancement and use of the various transport sectors, geographical location (including climate), and also the sensitivity of the elements of the environment. Considering contemporary transport hazards, it is important to prevent them from occurring, and when that is not possible – limiting their impact on the environment and reducing the scale and extent of negative impacts. The impact of rail transport on the environment and safety is much lower compared to road transport. The impact of rail transport on the environment mainly comes from the emission of noise and vibration, pollution (from diesel locomotives) and land occupation. The article presents information on the current legal conditions regarding the emission of pollutants from rail vehicles. Information with reference to research tests and emission limit values was included. The subject of tests in real traffic conditions was also mentioned as the direction of changes in vehicle homologation tests.

Schlüsselwörter

  • rail vehicles
  • combustion engines
  • exhaust emission
  • research tests
  • transport
  • environmental protection
Uneingeschränkter Zugang

Studies of Electric Drive with Hydrostatic Support

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 265 - 274

Zusammenfassung

Abstract

In this article, results of experimental studies concerning the relief of a city car electric drive by means of hydrostatic drive support are presented. Experimental studies were performed using a laboratory station built for this particular purpose. Studies of basic properties of elements of hydraulic system and resistances in the mechanical system were performed. The results of experimental studies of a chosen sub-assembly of hydrostatic drive (i.e. hydro-pneumatic battery) are given. The resistances within mechanical system (flywheel) were determined.

In the considered hybrid drive, electric drive is cyclically supported by hydrostatic drive during acceleration or regenerative braking of the vehicle. The results of experimental studies presented in this article were obtained on a designed and built laboratory station representing a model of a lightweight delivery van for city traffic and equipped with the studied hybrid drive. The obtained results suggest that there is a possibility considerably to increase the effectiveness of energy conversion in the electric drive of the vehicle by means of hydrostatic support. By applying the hydrostatic support in the electric drive, the load on the electric battery decreased, which positively influences the length of operation time.

Schlüsselwörter

  • hybrid drive
  • energy consumption
  • energy efficiency
  • regenerative braking
  • city traffic
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The Evaluation of Viscosity Properties of Engine Oil – Marinol RG 1240 After Working in Various Types of Engines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 275 - 281

Zusammenfassung

Abstract

The lubricating oils are a liquid substance, consisting of a base (mineral, synthetic or vegetable) and selected additives. They can used for lubricate internal combustion engines, so they called – engine oils. For proper functioning of the engine, lubricating oil have to fulfil basic requirements: the main function is to enable the formation of a film of oil between the moving parts which reduces friction and wear, assisting in cooling, keeping the compression ratio, reducing corrosion, filling in all micro ridges on the surface of cooperating components, sealing the combustion chamber etc. The most significant property of any lubricating oil is viscosity, which is the measure of its resistance to gradual deformation by shear stress or tensile stress. The important feature is that property of viscosity changes during the exploitation process of oil, it may increase and decrease. That is why, for engines it is important not only to choose the type of oil correctly but also to frequent monitor the viscosity. In the article, the author shows how the viscosity of marine engine oils changes after working in different types of engines. The experiments were conducted using the method of the rheometer Haake Mars III of Thermo Scientific. The samples of engine oil – Marinol RG 1240 were collected after various periods of use in three different engine types Cegielski-Sulzer.

Schlüsselwörter

  • engine oil
  • viscosity
  • marine engine
  • lubricating system
  • rheometer
  • Marinol RG 1240
Uneingeschränkter Zugang

Rules for the Organization and Functioning of a Maintenance Support System in a Military Unit – Selected Aspects

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 283 - 288

Zusammenfassung

Abstract

One of the most important tasks of military logistics is to ensure proper use and technical maintenance of armaments and military equipment. Providing maintenance support services on the modern battlefield, with its saturation with complex technical solutions, poses a significant challenge for the logistics system of the Armed Forces of the Republic of Poland. It is the duty of military logistics to adjust the potential of logistical sub-units as well as the organizational scheme and procedures of logistical support in accordance with changes occurring in the field. In times of peace, maintenance support services are focused on preventing equipment malfunctions. If a given piece of equipment becomes non-operational, their task consists in restoring it to full working order, taking into account all economic considerations.

The vehicles should feature good traction characteristics in varied terrain and be adapted to operation in both cold and hot environments. The training of repair sub-unit staff remains an important element affecting the standard of maintenance support.

Schlüsselwörter

  • maintenance support
  • operation
  • technical maintenance
  • automotive vehicle utilization
Uneingeschränkter Zugang

Static Analysis of the Tipper Semi-Trailer Frame

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 289 - 294

Zusammenfassung

Abstract

The article presents a static analysis of the existing three-axle tipper semitrailer using the finite element method. The tipper trailer frame must be strong enough to carry loads from the load while driving, during an accident and especially when emptying the load box when a very large part of the load is pointing at the rear of the frame. Frames are usually made of low-alloy steel with increased strength, most often of grade S355J2G3; duralumin alloy frames are also used.

The currently designed semi-trailer frames are becoming more lightweight while the required load capacity and durability are retained. This is possible thanks to the use of computational methods by the engineers in this finite element method. Static analysis allows for the determination of stress and deformation in the loaded frame and also a possible modification of the frame. The aim of the work was to investigate the influence of the position of the crossbar on the level of stress and deformations for three different load situations of the frame.

Schlüsselwörter

  • static balance
  • global static
  • web local buckling
  • Finite Element Method
Uneingeschränkter Zugang

Analysis of Calculation Models of Scaffolding Constructions in Light of Experimental Tests Results of Constructive Scaffolding Module

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 295 - 306

Zusammenfassung

Abstract

The concern of the article is the analysis of multiple computational models of scaffolding construction, taking into account the experimental results obtained for a representative scaffolding construction module. Analyses of 25 distinct models have been performed, allowing selecting models that most accurately predict deformations of the real construction. The article deals with the issues of elastic-plastic second-order analysis in relation to the working anchored scaffolds and it is focused on the standardization of computational models for engineering calculations. Including in calculations the plastic bearing capacity reserve and using objective calculation procedures, allows optimal designing of the scaffolding and evaluating of the load capacity. Structural model analyses were carried out in terms of their conformity with the actual construction. For comparative purposes, the results of the analyses of individual models were evaluated according to different verification formulas to determine the extent of their applicability. The purpose of the article was to test the behaviour of the system under the influence of constant horizontal forces reflecting the influence of wind and rising from zero until destruction due to the vertical load.

Schlüsselwörter

  • static analyses
  • scaffold structures
  • computational models
  • different verification formulas
  • load evaluating
Uneingeschränkter Zugang

Study on Fuel Injector with Hydraulic Amplifier (HADI) on the Example of Mercedes-Benz Actros Vehicle with Om 471.9 Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 307 - 316

Zusammenfassung

Abstract

One of the recent trends in heavy-duty engines has been the introduction of common rail injector with hydraulic amplifier (HADI − Hydraulically Amplified Diesel Injector) capable of considerable fuel pressure injection increase in reference to fuel pressure prevailing in rail of common rail fuel system. An example of a solution of this type of injectors is the two-valve CRIN4 injectors manufactured by Bosch. They allow the control of the fuel flow rate during injection process and therefore have an impact on the combustion process. In this article, advantages related to their use are described, which allow the engines with such injectors to meet the limits of the admissible content of toxic compounds in the exhaust gases defined in the EURO VI standard. An experimental study of the operation of the Bosch IV generation common rail system was performed on the Mercedes-Benz Actros. During measurement engine load, engine speed, waveforms (electric currents) controlling operation of the selected injectors, fuel pressure in the rail and the control current of high pressure pump control valve (metering unit) were registered. Interpretations of recorded waveforms were made, indicating the areas of application of the various modes operation. The use of CRIN4 injectors for the rapid reduction of fuel pressure in rail was observed, which supports the metering unit (ZME) for pressure control.

Schlüsselwörter

  • diesel engines
  • common rail systems
  • fuel injectors
  • injection rate modulation
  • boot injection
Uneingeschränkter Zugang

Analysis of Influence of the Shape of Cutting Insert on Change of the Parameter Value Describing the Deviation of the Profile of Surface Roughness

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 317 - 323

Zusammenfassung

Abstract

The article presents the influence of the shape of the cutting insert on the surface roughness of the material after medium-fine turning machining. The analysis of measurements of the Ra parameter describing the arithmetic mean deviation of the surface roughness profile from the centre line of the profile by the mechanical and contact method was made using the Hommel Etamic Waveline 20 profile (Gdynia Maritime University). The tests were carried out on three stainless steel X2CrNiMo17-12-2 / 1.4404 shafts with a diameter of 80 mm, subjected to medium-precision turning machining at a length of 270 mm, using three cutting inserts made of tungsten carbide shaped T – triangular, C – rhombic, W – trigonal manufactured by Pafana. Values of used parameters are turning speed Vc = 150 m/min, depth of cut ap = 2 mm and feed f = 0.2 mm/rev. The parameters have been selected according to the manufacturer’s recommendations. The tests were carried out three times, five measurements on the length of the turned part of the rollers. The first test was made after collecting one layer of material, the second test was carried out after collecting five layers of material, and the third test was made after collecting nine layers of material. The article describes the differences between the used tiles and their effect on surface roughness, presents the results of the research, charts of measurements with averaged values and descriptive statistics of the Ra parameter were presented. It was noted that for all measurements of the Ra parameter, the smallest values were obtained using a W-shaped cutting insert. The Ra parameter using the C and T shaped plates increases with each subsequent measurement. The largest value of the Ra parameter is obtained using the T.

Schlüsselwörter

  • surface roughness
  • turning machining
  • cutting insert
  • technological quality
  • contact profilometer
Uneingeschränkter Zugang

The Influence of Electrochemical Battery Aging Process on an Electric Vehicle’s Range

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 325 - 331

Zusammenfassung

Abstract

This article presents the influence of aging processes of the electric vehicle’s electrochemical battery. The increasing number of hybrid and electric vehicles increases the demand for durable and efficient sources of energy storage for vehicles. The vehicle’s declared range is reduced over time.

This is due to the aging of the battery that causes loss of its capacity and loss of its power. To minimize this phenomenon, manufacturers use counteracting solutions that include mounting additional cells in the battery that are switched on when the battery controller identifies a particular battery cell’s failure or high degradation. This is due to the deep and shallow discharges of the battery, the number of charge and discharge cycles, and the age and technology of battery packs.

AMESim software was used for the simulation of the electric vehicle. The research was based on modelling the range of the vehicle whose cell capacity includes processes related to aging of the battery. An aging cell algorithm causes the capacity to drop and consequently reduces the range of one full charge. By modelling aging processes, it is possible to determine the battery’s probable capacity loss during vehicle use and to estimate how these processes affect the vehicle’s range.

Schlüsselwörter

  • battery
  • simulation model
  • electric vehicle
  • LiFePO
Uneingeschränkter Zugang

Jet Aircraft Data Acquisition Systems

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 333 - 338

Zusammenfassung

Abstract

The article presents systems, which record parameters of flight in modern aircraft F-16, which was delivered to Polish Airforce in 2006. With the current level of technical development of the aviation industry, data acquisition systems are an important element of all aircrafts. These systems are responsible for the flight safety, allow reading and storing the most important flight parameters, and combined with digital control and safety systems allow to counteract dangerous situations, which especially can happen often in the case of military aircraft such as the F-16 due to their combat purpose. Systems records basics parameters of plane and engine, as specific fuel consumption or height of flight provides video and audio recording, and aerial combat assistance. These systems record even failures of a braking system during landing. Thanks to modern technology, and devices like those described in this article, F-16 is one of the best fighters in the world. The amount of data provided by analogue and digital sensors is so large that it requires the partitioning of parameters and use of several basic recorders of the entire system is the unit called DAU, or Data Acquisition Unit, which records the most important flight parameters, such as flight time, engine speed, or altitude.

Schlüsselwörter

  • aircraft
  • safety
  • jet engine
  • aviation
Uneingeschränkter Zugang

Study of The Influences of Blending Different Proportions of Propane into Methane on Combustion Characteristics at the Knock Threshold by Using RCM

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 339 - 346

Zusammenfassung

Abstract

A spark-ignited Rapid Compression Machine (RCM) has been used to investigate the influences of the different proportions of methane-propane mixtures on the combustion characteristics at knock threshold operating condition. First, the threshold operating points of the mixtures have been obtained and the results indicated that the piston driving pressure reduces from 142 bars to 90 bars as the propane content in the mixture increases. As a spark plug was fitted in this RCM, the optimum spark timing was also investigated. It was established that spark timing should be set synchronize with the piston at TDC, due to the free movement of the piston. In most RCMs, piston can move toward TDC following the equilibria of forces due to the absence of con-rod. Finally, knock intensity of the different mixtures has been studied. Pre-heating system in RCM with and without trace heating system; effects of flow-rate and lambda variations on peak pressure, ignition delay time and ARR; threshold operating conditions of pure methane, 90% methane and 10% propane, 80% methane and 20% propane, 70% methane and 30% propane; effect of driving pressure on the knocking intensity for mixture of methane and propane for heavy and light knockings are presented in the article.

Schlüsselwörter

  • Rapid Compression Machine
  • knock threshold operating condition
  • peak driving pressure
  • knock intensity
Uneingeschränkter Zugang

Gurney Flap and T-Strip Alternatives in Application to Typical Aircraft Steer Surface

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 347 - 354

Zusammenfassung

Abstract

Classic Gurney flap and double Gurney flap (called T-strip) are well-researched trailing edge modifications used in aerospace engineering. However, one of the inevitable effects of their use is the aerodynamic drag increase at low lift conditions, concerned as the major drawback of these solutions. This article presents Gurney flap and T-strip passive alternatives, which guarantee similar advantages in terms of e.g. lift enhancement, but without significant drag increase. Their aerodynamic analysis was performed on the application case of a typical symmetrical aircraft stabilizer with movable steer. Both solutions, consisting of plates nearly parallel to the direction of flow, were modelled as two-dimensional cases and CFD calculations were performed for specified range of angles of attack and steer deflections. Obtained aerodynamic characteristics allowed assessing the influence of selected modifications on the stabilizer effectiveness, as well as on hinge moment characteristics. The flow pattern changes in the presence of analysed devices were also investigated. In this way, performed analysis provided valuable information about the advantages and disadvantages of using of such devices in comparison to classic Gurney Flap and double Gurney flap. The results showed that using proposed solutions gives the possibility of significant reduction of the aerodynamic drag of the whole stabilizer at low lift conditions, while still maintaining favourable lift characteristics.

Schlüsselwörter

  • CFD
  • steer
  • stabilizer
  • Gurney flap
  • T-strip
Uneingeschränkter Zugang

Impact of the Driver Behaviour on the Energy Recuperation in an Electric Vehicle

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 355 - 362

Zusammenfassung

Abstract

In recent years, energy recuperation systems have been used more and more often. This is due to the rapid development of electric and hybrid cars. In view of the growing technology that allows for a recuperation system efficiency increase, it is important to consider whether the weakest link is in this case not the driver and his ability to customize the driving style to the needs of energy recovery. This article attempts to answer this question. For that purpose, the special road tests were conducted in a real urban traffic. Two drivers were involved, each of whom used alternating recovery and non-recovery driving style. In total twelve road tests, realisations have been completed. The results of the measurements were entered into a mathematical model that simulated the work of the energy recuperation system. It allowed estimating how different recovery systems can work in the conditions of conducted tests. On this basis, an analysis was made both in terms of the total amount of energy that can be recovered in the case of recuperative and non-recuperative driving, and analysis of the recuperation system working and the real impact of the driver’s driving style on the energy stored in the car’s battery. Basis on the conducted considerations authors noted that use of recuperative driving technique could increase the amount of stored braking energy on average by 60%. It was also seen a significant impact on the energy waveform in the battery.

Schlüsselwörter

  • energy recuperation
  • driver behaviour
  • braking energy
  • mathematical model
Uneingeschränkter Zugang

Simulation Investigation of Operational Conditions of Rotor for High-Speed Compound Helicopter

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 363 - 370

Zusammenfassung

Abstract

The article presents results of simulations concerning possibilities of rotorcraft performance enhancements for compound helicopters with introduced additional wings and propellers. The simple model of helicopter including a point mass of fuselage and a rotor treated as a disk was used for calculations of helicopter flight equilibrium conditions. For the defined flight states, the more detailed model of elastic blade was applied to compute magnitude of rotor loads and level of blade deformations. The model of elastic blade includes out-of-plane bending, in plane bending, and torsion effects due to variable aerodynamic and inertial loads of rotor blades. Equations of motion of rotor blades are solved applying Runge-Kutta method. Taking into account Galerkin method, parameters of blade motion are computed as a combination of assumed torsion and bending Eigen modes of the rotor blade. The six-bladed rotor with stiff connections of blades and hub was applied for comparison of flight envelope for conventional helicopter and versions of compound rotorcraft with additional propellers and with wings and propellers. Simulations indicate that, in the case of compound helicopter configuration, achieving the operational flight conditions at high speed of 400 km/h is possible without generating excessive loads and blade deformations. The results of calculations of rotor loads and generated blade deflections are presented in form of time-run plots and as rotor disk distributions, which depend on radial and azimuthal positions of blade elements. The simulation investigation may help to define demands for rotor of high-speed helicopter.

Schlüsselwörter

  • compound helicopter
  • rotor loads
  • blade deformation
Uneingeschränkter Zugang

Robust Optical Flow Estimation Applied to Particle Image Velocimetry Images for High Resolution Velocity Measurements

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 371 - 377

Zusammenfassung

Abstract

The article discusses application of Robust Optical Flow Estimation for increasing of Particle Image Velocimetry measurement resolution. Nowadays, one of the promising approaches for increasing the performance of the PIV systems is application of the Optical Flow Estimation for image analysis. Nevertheless, some of the OF implementations do not perform well in case of motion discontinues typically occurring in the PIV images. The purpose of this study is to validate the performance of the Robust Optical Flow Estimation. The tests were performed on simulated images of vortex flow and the results were compared with displacement fields calculated with the typical correlation PIV algorithm. The velocity for high and medium particle concentration was similar for Optical Flow and PIV-like analysis. Furthermore, the performance of the robust optical flow framework was tested with images corrupted with blurs and occlusions. The tests proved good performance of proposed analysis in case of non-Gaussian sources of measurement errors. The robust estimation framework performed well in the case of common image artefacts and proved to be a promising method for precise PIV flow measurements. The presented approach can be useful in development hybrid OF-PIV post processing software aimed for high-resolution measurements and provide a help in designing of experimental investigation of microscale fluid flow phenomena.

Schlüsselwörter

  • Particle Image Velocimetry
  • optical flow estimation
  • particle image density
  • image occlusions
Uneingeschränkter Zugang

Influence of Thermal Signal Characteristics on Defect Detection in GFRP by Active Optical Thermography

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 379 - 383

Zusammenfassung

Abstract

Advances in technological development, since the 1990s, has been associated with the development of two basic domains of knowledge: information technology and material engineering. The development of material engineering is directly related to composite materials. One group of composite materials are fibre-reinforced composites. Due to their unique properties, they are used in various fields of engineering sectors. Composites reinforced with glass fibre (GFRP) are the second most commonly used composite after carbon fibre reinforced composites (CFRP). GFRP in many cases can replace traditional structural materials, which are usually made from metal. Of course, this material is exposed to damage both in production and operation phases. One method of non-destructive testing that effectively identifies defects in GFRP is active optical thermography. In this method, for thermal stimulation of the tested material, various types of heat sources are used for example: heating lamps, lasers etc. This article analyses the influence of the characteristics of the thermal optical sources on detection of typical defects in GFRP.

Schlüsselwörter

  • non-destructive testing
  • composite material
  • IR thermography
Uneingeschränkter Zugang

Use of Biofuels in a Compression-Ignition Engine – Comprehensive Technical and Economical Analysis

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 385 - 393

Zusammenfassung

Abstract

The assessment of renewable fuels on the basis of the results of internal combustion engine’s tests is not clearly good or not good. Biofuels can be a part of sustainability from energy sources, energy security and energy diversity point of view. But they cannot be assessed better compared to the fossil diesel as for their combustion and air pollution and the engine’s external parameters. Comparison test series has been conducted with three different fuel and their controlled blends. These fuels were fossil diesel, the conventional, standardized biodiesel, and a new type biodiesel, which is the so-called TBK-biodiesel. These tests covered the physicochemical properties of the fuels, the engine external parameters, the combustion parameters and the exhaust emission of an internal combustion compression ignition engine. Furthermore, external costs have been calculated based on the emission results. Physicochemical properties, engine parameters, combustion parameters, exhaust emission and external costs have been observed as parameter groups, which contain many parameters. A complex evaluation could be built with the help of such kind of parameter set. On the basis of the results, it can be established that almost in the most cases the direction of the parameters’ changes is negative. Thus, the evaluation’s centre of gravity has been observed as shifted in the negative direction.

Schlüsselwörter

  • conventional biodiesel
  • TBK-Biodiesel
  • complex evaluation
  • Diesel engine
  • combustion
  • emission
Uneingeschränkter Zugang

Exhaust Emission Estimation in Freight Transport Systems

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 395 - 406

Zusammenfassung

Abstract

Modelling of transport systems is a complex issue requiring taking into account many factors that allow for the mapping of the real system and thus allowing decision support. In the era of increasingly higher requirements for services, transport also faces the challenges of sustainable development. Therefore, it is necessary to conduct research both in the sphere of technical and organizational solutions aimed at limiting pollutant emissions. Mapping in the model the negative impact of transport on the environment allows for planning the implementation of the transport service taking into account the pro-ecological criterion. This is particularly important in urban areas where traffic and especially heavy goods vehicles are particularly onerous for inhabitants and require limiting transport work in the city area and the use of environmentally friendly rolling stock. The aim of the article is to present the considerations regarding the modelling of transport systems including pollutant emissions. The article introduces the problem of cargo distribution and a review of the models of estimation of pollution emission in the micro and macro scale was carried out. Next, a mathematical model was proposed which is a variant of the Vehicle Routing Problem of the so-called Green VRP. In the distribution model was used COPERT methodology for estimation of harmful substance emission. In article examples of calculations carried out on the example of the city of Warsaw for the organization of cargo distribution due to the CO emission criterion was presented. The article ended with a short synthesis of the work carried out.

Schlüsselwörter

  • transport
  • freight transport
  • modelling
  • emission estimation
  • COPERT
  • Green VRP
Uneingeschränkter Zugang

Effective Harvesting of Braking Energy in Electric Cars

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 407 - 422

Zusammenfassung

Abstract

Regenerative braking and damping are effective approaches for electric cars to extend their driving range. A disk Faraday generator regenerative braking strategy integrated with controlled charging of a supercapacitor is developed in this article to advance the level of energy-savings on the car board. The kinetic energy of the car suspension during driving regenerated effectively to electric energy by using shock absorber is harvested and then used to charge the vehicle’s battery, the power electronics and the supercapacitor. One of the advantages of supercapacitors is their high power capability, which is applicable for high rate of charging and discharging operations like motor starting and regenerative braking of an electric vehicle. This article presents a new charging method for supercapacitors. Common for regenerative braking and damping chargers for supercapacitors are usually equipped with electronic PWM converter performing two states of operation per switching cycle. A simple open-loop control system is applicable for the whole charging state. The proposed circuit consists of a minimum number of components. It is free of stability problem and protects itself from being overloaded by supercapacitor with zero initial charge. Simulation results for regenerative braking processes corresponding to three velocity tests are included.

Schlüsselwörter

  • urban transport
  • environmental protection
  • electric cars
  • energy harvesting
  • braking energy recovering
  • damping energy recovering
  • supercapacitors
  • simulation
Uneingeschränkter Zugang

The Errors of the Numerical Calculations of Dynamic Characteristics of Cantilever Beam Mounted on the Plate

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 433 - 440

Zusammenfassung

Abstract

The safety, comfort of the crews, stability, economics of the equipment when ship operating is the leading requirement in the field of designing and manufacturing marine structure and machinery. As a result, all parts of the ships must be tested and inspected to meet the basic safety requirements of the shipping association. The design, manufacture, testing in the maritime field in general and shipbuilding sector in particular are expensive, time consuming: such as aerodynamic experiments of the engine, collision test, ship manoeuvring, vibration test and balance of deck beams, hull beams, hatch covers, shafts...thus experimental works are sometimes impossible. Along with the development of computer science, many numerical models and software programs have been developed to solve these difficult problems. There are many numerical modelling methods, starting with the finite difference method, the boundary element method, the finite element method, the no mesh method, the weight residue or the energy method. The Work will be limited to the analysis of the most popular numerical modelling method - finite element method using Patran and Nastran software. In the first step of our research, T-beam was analysed as a part of ship hull structure (thin-walled structure). The article goes into the analysis of the accuracy of selected numerical models for the natural vibration frequency of the T-beams mounted on the plate. After modelling, calculating the natural frequency of the T-beam using the Patran - Nastran software, the results were compared with the theoretical values. From that, we evaluate the dispersion and error of different numerical models and select the optimal numerical model. Optimal model will be used for modelling full ship hull with superstructure.

Schlüsselwörter

  • T-Beam
  • vibration
  • ship structure
  • modal analysis
  • FEM errors
Uneingeschränkter Zugang

Optimization of Gassing-Up Operation Based on Comparative Analysis of Two Twin Ethylene Carriers

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 441 - 446

Zusammenfassung

Abstract

The article consists comparative analysis of the gassing-up operation – purging cargo tanks with cargo vapour, on gas carriers carrying primarily Ethylene – one of the most expensive cargo of all hydrocarbons carrying by the sea. The source of the problem constitutes similar densities of both gases under specific conditions – Ethylene and Nitrogen – a gas that tanks are purged before gassing-up. The analysis is made for considerable optimization of the process. The comparison of gassing-up methods is based on tests and measurements on two particular twin gas carriers. In both cases different methods – parallel and cascade were chosen to do the gassing-up (parallel means to purge tanks separately at the same time, cascade means to purge tanks one after the other) what allows specifying beneficial procedure. What was estimated during voyages were technical parameters measured during gassing-up, time of the process and the most important information – loss of the cargo. Analysis of particular stages of the operation also allows estimate the level of gas mixing in the tank. The basic purpose of this profile, based on Ethylene loss, is selecting alternative for carrying this operation in more efficient way, what constitutes determining the most proper method of gassing-up – parallel or cascade and setting temperatures, pressures, mass flows which minimize vapour of Ethylene vented to the atmosphere.

Schlüsselwörter

  • gassing-up
  • gas mixing
  • ethylene
  • nitrogen
Uneingeschränkter Zugang

Car Tyres with Reduced Energy Consumption

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 447 - 456

Zusammenfassung

Abstract

The objective of this publication is to present the changes that are currently made to the tyre structure in order to reduce its rolling resistance including the rubber compound, tread pattern and tyre support structure. Based on a broad literature review the authors present a history of changes introduced in the construction of tyres aimed at reducing their share in the energy losses needed to overcome the resistance of rolling wheels in the car’s movement (at present it reaches even 50%). They indicate a significant conflict resulting from the rubber properties using the data sets available on the labels of summer and winter tyres in which the improvement of wheel adhesion leads to increased rolling resistance. In the next part, the basic factors determining the rolling resistance of tyres are approximated, focusing on those related to their construction. The influence of the rubber loss factor is described which values at different deformation frequency (turning the wheel 101-102 Hz and its braking at 104-105 Hz). It determines the interaction of the rubber with the road surface. Various ways of actions are shown to reduce the losses occurring during the deformation of the tyre: the use of silica as a rubber filler and the introduction of nanotechnology to control the rubber crosslinking process, reducing the volume of rubber used to build the tyre coating, simplifying the tread pattern and changing the tyre diameter size to a larger one (treatment used in electric cars). Particular attention was also paid to the weakness of the changes, i.e. the increase of the noise generated by the more elastic coating of the tyre and the possible directions of counteracting this phenomenon were signalled.

Schlüsselwörter

  • energy consumption
  • rolling resistance
  • tyre construction
  • tyre tread rubber
  • tread pattern
Uneingeschränkter Zugang

The Influence of the Compression Ratio Error and the Pressure Error at the Beginning of Compression on the Heat Release Characteristic Calculated Based on Indicator Diagram Marine Diesel Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 457 - 463

Zusammenfassung

Abstract

In the operational diagnostic of marine engines, the analysis of indicator diagrams is important. In addition to analysing changes in the values of indicated parameters, should be aimed to oriented broader analysis, including the determination on the basis of experimental indicator diagram of heat release characteristics during the combustion process.

In the diagnostics of piston engines, including marine engines, special interest arouses to use single-zone model based on indicator diagrams as a source of information. There are calculated heat release characteristics: net heat release (Q) and intensity of heat release (q).

The article discusses the impact problem the characteristics of heat release calculated based on experimental indicator diagram various errors – the compression ratio error and the pressure error at the beginning of compression.

Based on the results of own research we analysed the impact on the characteristics of heat release the compression ratio error and the pressure error at the beginning of compression.

The effect of the errors on the course of characteristics q and Q, to the typical marine medium speed engine Sulzer A25/30 and low speed engine Sulzer RTA 76 shown.

Schlüsselwörter

  • marine diesel engine
  • indicated parameters
  • indicator diagram
  • heat release characteristics
  • compression ratio
  • compression pressure
Uneingeschränkter Zugang

Material Recovery as an Opportunity of Immediate Introduction of Eco-Friendly Transport System (Vehicles)

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 465 - 474

Zusammenfassung

Abstract

The article presents an analysis of the need to introduce pro-ecological solutions at the fuel sector of industry, resulting from dynamic economic development, and environment protection requirements. The forecasts on the number of vehicles in the world and the subsequent growth of interest in alternative fuels are presented. The advantages of using these fuels as compared to petroleum fuels and electricity are described. The presented analysis emphasizes the context of EU legislation on environmental requirements. At the same time, it was pointed out the need to obtain the required technical and energy characteristics of alternative fuels, the competitive costs of their production, and important environmental aspects. Taking into account these premises and the principle of circular economy closed circuit, alternative fuels from organic waste, in particular from enormous amounts of organic non-biodegradable wastes (packaging, multi-material fabric, rubber, tires) were proposed. It has been shown that thermal decomposition by thermolysis, described briefly in the article, can be a method suitable for a wide economic application within the alternative fuel production system. Based on literature data and own experience, it has been found that the quality of fuels (oil, gas) obtained from the thermal decomposition of organic and mixed waste is not different from the requirements for the best quality raw materials used in the production of petrol and may even exceed the properties of petroleum. Introduction of the system of regional production and distribution of alternative fuels from waste could be remarkable driver of small towns and rural areas revitalization and development, while supporting build up and improvement of local communities.

Schlüsselwörter

  • road transport
  • material recovery
  • environmental protection
  • thermolysis
  • alternative fuels
Uneingeschränkter Zugang

Analysis of Damage of the Cooling Aggregate in Vehicle with Cold Storage Chamber

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 475 - 482

Zusammenfassung

Abstract

Vehicles with cold storage chambers realize the transport of fast spoil articles. The cooling system of such chamber is its critical subsystem, the essential component of which is a cooling aggregate driven by vehicle combustion engine via belt transmission. The main assembly of the analysed aggregate was the axial five-piston compressor. Small aluminum pistons were led in cylinders in fixed head made of aluminum alloy. Such pistons were driven through steel tappets, mating through their spherical surfaces with spherical seats made in small pistons. Through their front surfaces, placed opposite to the spherical surfaces, the spatial disc cam made of aluminum alloy drove small pistons. The cam was mounted on the steel shaft. The co-operation of described parts was in presence of refrigerant oil. The abrasive and fatigue wear of elements occurred. Because of long-term utilizing of the aggregate the damage of radial sealing ring occurred. Then, external impurities of high hardness got into the contact zone between the mating surfaces. The main aim of the study was to analyse consequences of such fact. The failure was noticed in the form of wear of disc cam, front surfaces of tappets, and the plastic deformation in the spherical surfaces of the seats. Then, due to deformation and the displacements of the rotating shaft, wear of the side surface of disc cam during contacts with small pistons surfaces took place. Moreover, we noticed wear of the side surfaces of the pistons and the cylinders mating with them in the fixed head. In the article, we present figures of damaged surfaces of elements and results of the SEM analysis of spherical surfaces of tappets. The material transfer occurred between the spherical surfaces of tappets and their seats.

Schlüsselwörter

  • cooling aggregate
  • combustion engine
  • sealing ring damage
  • failure
  • blurring
Uneingeschränkter Zugang

Results of the Crash Tests of Electric Cars

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 483 - 490

Zusammenfassung

Abstract

The work presents the results of crash tests carried out with six electrical car models (from 2012-2013), with the weight of 1200-2300 kg (Smart Electric Driver, Mitsubishi IMiEV, Nissan Leaf, CODA, Ford Focus BEV, Tesla Model S). The results were published on the Internet by the National Highway Traffic Safety Administration (USA), and the tests involved a car travelling at the speed of 56 km/h, hitting frontally into a non-deformable (stiff) barrier, positioned perpendicularly to the car’s direction of movement. Particular attention was paid to the deformation of the car after hitting the barrier, so-called stiffness characteristics of the frontal crumple zone, and to the loads on the dummies placed at the driver’s and passenger’s seat (Hybrid III, a 50-centile man and a 5-centile woman). Results of the tests with electric cars were compared with the results of the tests with over a hundred of combustion engine cars with similar weight and type of car body (sedan, hatchback). The tests proved that, in the majority of electrical cars tested, the deformation of the frontal crumple zone after hitting an obstacle is larger than in case of similar cars with internal combustion engine. Because of that, the dynamic loads on the occupants of the vehicle tend to be smaller, as indicated by measured loads on the heads and chests of the dummies. The results may suggest that the frontal crumple zone may be better constructed in the case of electric cars, while the design possibilities regarding that area are limited in standard cars due to the combustion engine, which is not deformed during the accident, which makes it more difficult for the energy of the crash to dissipate.

Schlüsselwörter

  • road transport
  • vehicle safety
  • crash tests
  • safety of passengers
  • electric vehicles
55 Artikel
Uneingeschränkter Zugang

Properties of the Baltic Crude Oil in the Oil-in-Water Emulsion Form: Excitation-Emission Spectra

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 7 - 14

Zusammenfassung

Abstract

Due to the fact that marine environment contamination by oil substances are not uncommon, it is necessary to improve the ability of determine their origin. Therefore, research on the possibility of recognizing the type of oil using its individual characteristic manifested in the processes of fluorescence excitation has been undertaken. Oil pollutants present in seawater mainly coming from ship drives, tankers, pipelines or sea bottom seeps, moreover oil leaks from offshore extraction equipment also are possible. For this reason, the crude oil extracted from the Baltic Sea deposit in the Polish Maritime Areas has been chosen for tests. Fluorescence properties of water containing small amounts of oil (concentrations from 5.59 to 55.4 ppm) in the form of oil-in-water emulsion were tested. Individual samples were assigned matrices of fluorescent values for different wavelengths, while excited by monochromatic light also for different wavelengths. The obtained matrices were visualized as a contour maps and 3D charts. For considered concentrations of crude oil dispersed in water, the wavelength-independent fluorescence maximum was determined. Obtained result indicates that in the studied wavelength range, the total fluorescence intensity is proportional to the oil concentration only for the lowest oil concentrations. The analysis of the objective parameter of the difference between the shapes of spectra indicates the similarity of the spectral shape for the lowest oil concentrations. These results are the methodological suggestion, that for the purpose of identifying the type of oil dispersed in water, spectra should be determined for sequences of different dilutions, until the excitation-emission spectra shapes become independent from the oil concentration.

Schlüsselwörter

  • crude oil
  • excitation-emission spectra
  • fluorescence
  • seawater
Uneingeschränkter Zugang

Applications of Metallic Composites in the Automotive Industry and their Machining by the EDM

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 15 - 23

Zusammenfassung

Abstract

The article deals with the problems of application of aluminium matrix composites in car industry and electro discharge machining (EDM) of selected composites, which are used for engine pistons.

Composites with Al+20%Si+3%Cu+1%Mg matrix were manufacturing by the powder metallurgy route in the process of cold compaction, degassing and hot extrusion. As the reinforcing phase Al2O3 particles with average size of 3, 9, 23 and 53 μm were used. Samples had constant reinforcing phase 5 and 10 % by volume. Electro discharge machining was performed using machine equipped with RLC generator. Four modes of energy of single discharge Ei in the range of 0.165 to 2.268 mJ were applied. EDM was carried out in a free – system. The main parameters determined after machining were volumetric productivity Vw (mm3/min) and roughness of the machined surface expressed as Ra. It was shown that energy of single discharge influence mainly on the EDM process running. The higher was Ei, the higher were value of Vw. Increasing particle granularity from 3 to 53 μm caused decreasing in process productivity 13 to 19%. Ei affects the surface roughness during EDM. The value of Ra increases as this energy increases. When the size of reinforcing particles is growing, roughness parameter Ra is also growing.

Schlüsselwörter

  • aluminium matrix composites
  • automotive industry
  • electro discharge machining
  • EDM productivity
  • surface roughness
Uneingeschränkter Zugang

Concept of an Expert Diagnostic System of the Turbine Engine’s Flow Path Elements

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 25 - 32

Zusammenfassung

Abstract

The article presents a concept of an expert diagnostic system of the turbine engine’s flow path (compressor – combustion chamber – turbine) elements. The system adopts diagnostic signals obtained with the use of non-destructive methods implemented on the non-operating engine. The aim is to detect and assess early stages of damage to selected elements of the engine. The achievement of a reliable diagnosis on the condition of the elements requires the application of a set of diagnostic methods and carrying out the inference, including knowledge about the degradation processes of elements and correlation of the diagnostic (signals) tests results obtained with various methods. A convenient tool, which supports solution of such a set problem is an expert system, which on the one hand, makes it possible to organise the existing formal knowledge, and on the other hand – to use non-formal, or even uncertain, knowledge. The presented concept of the expert diagnostic system is based on PC-Shell system of AITECH Polish Company.

Schlüsselwörter

  • engine
  • diagnostics
  • expert system
  • knowledge base
Uneingeschränkter Zugang

New Methods of Marine Power Plant Diagnostics

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 33 - 39

Zusammenfassung

Abstract

Up-to-date, of high-tech design techniques of machine operation require constant monitoring on some levels. Generally, the monitoring today is limited to failure detection and machinery components check.

The Marine Engineering Faculty of Gdynia Maritime University designed the System for Marine Engine Operation Assistance on the basis of Sulzer Diesel AL 25/30 testing station.

The engine modernization and wider research and survey capabilities resulted in engine operation quality improvement, marine power plant research enhancement. The project broadens the research range and engine failure expertise as well as takes into consideration innovative marine fuel emissions. The goal has been achieved in the way of the test equipment modernization including: effective pressure sensors, high pressure fuel sensors, monitoring and visualization of the engine systems’ parameters, electronic indictors adopted to continuous operation at all cylinders in the same time, and high class decision aid computer equipment. Engine modernization and data base extension allow for carrying out a wide scope of research.

Additionally, the article presents innovative diagnostic solutions together with their applications.

Schlüsselwörter

  • diesel engine
  • diagnostics
  • roughness
  • surface
Uneingeschränkter Zugang

Influence of Flame Heating Parameters on the Hardness of Hardened C45 Steel

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 41 - 47

Zusammenfassung

Abstract

In this article, the impact of selected parameters of heating using a gas torch on the hardness of hardened alloy steels C45 was presented. The staff of the ship’s engine room sometimes uses flame hardening during casual repairs of the machines weared as a result of operational extortions. The purpose of emergency repairs is to restore the possibility of work of ship machinery and equipment for the duration of the vessel’s journey. An acetylene-oxygen torch was used to heat the steel. As the analysed parameters of the technological process, the heating time and the distance between the nozzle and the workpiece were selected. The values of the mentioned parameters have been selected so that the temperature of hardened steel is in the range from 800 to 1250 °C. The following values of the adopted machining parameters were used: the heating time was 60, 85 and 110 seconds, while the distance of the torch nozzle was 10, 20 and 30 mm. After heating, the samples were cooled by immersing in water. The research was based on a randomized orthogonal experiment plan. The purpose of the quantitative assessment of the influence of heating parameters on the hardness of hardened C45 steel, done statistical analysis variance analysis, multiple regression and mathematical optimization by the Tagichi method. Conducted tests and statistical analysis showed a significant effect of selected parameters of flame heating on the hardness of hardened C45 steel. The greatest influence on the hardness of the steel is the distance between the nozzle and the workpiece. The highest value of hardness was obtained using the following parameters of flame hardening: nozzle distance 30 mm, heating time 60 seconds.

Schlüsselwörter

  • hardening
  • flame heating
  • multiple regression
  • mathematical optimization
  • Taguchi method
Uneingeschränkter Zugang

The Issue of Energy Management in Walking Machines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 49 - 57

Zusammenfassung

Abstract

The energy management is a serious issue in the platforms of mobile robots, and especially walking robots. The solutions are sought so as to obtain the furthest possible range with the energy resources at the disposal. Properly adjusted configuration of the drives and the manner of energy management has a key impact on effectiveness of the drives. The article presents the most important features of the basic driving systems, possible configurations, and steering manners along with the assessment of their effectiveness. The article will present classical and hybrid drives. The authors present a sample analysis of energy “costs” of steering for the selected systems. The analysis will be supported with results of the simulation performed with the use of constructed computer models.

The guidelines for designing of the systems for walking platforms will be proposed, enabling to obtain high dynamics and energy efficiency of the system.

Schlüsselwörter

  • drive of a walking machine
  • energy costs in a mobile machine
  • linear load-sensing systems
Uneingeschränkter Zugang

Concept and Model of Terrain Wheeled Tractor with Hybrid Drive

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 59 - 65

Zusammenfassung

Abstract

The article presents construction concept of a tractor with hybrid, diesel-hydraulic and diesel-electric drive meant for the use in livestock holdings. The tractor is enabled to cover short distances with the combustion engine switched off. This solution uses independent engines to propel front and rear axles. This article presents a computer model and simulation results for the project of a hybrid, diesel-electric tractor based on a benchmark machine Fendt 516.

Aside from the ability to drive with diesel engine switched off, the proposed solution has additional positive features allowing smooth transition of relation of peripheral speed of the front and rear wheels. It enables to obtain higher tractive powers for various conditions in a broader range than for a traditional solution (with propelling both axles with one engine through different transmission systems and specific difference of peripheral speed of the wheels). The computer model was built on the basis of the benchmark machine.

Schlüsselwörter

  • terrain wheeled tractor
  • hybrid drive
  • computer model of a tractor
Uneingeschränkter Zugang

Diagnostic Aspects of a Crankshaft Torsional Oscillations Monitoring by IAS Measurement

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 67 - 74

Zusammenfassung

Abstract

Continuous monitoring of diesel engine performance under its operating is critical for prediction of malfunction development and subsequently functional failure detection. Analysis of Instantaneous Angular Speed (IAS) of the crankshaft is considered as one of non-intrusive and effective method of detection of combustion quality deterioration. The article contains presentation of attempt of monitoring of piston engine’s crankshaft torsional vibrations by measurement of Instantaneous Angular Speed at free, and power output ends of the engine’s crankshaft. The angular speed measurements was done using two optical sensors for reading the IAS, mounted at shaft line’s opposite ends, one at free end of the crankshaft and second at end of generator’s shaft. In the article is presented description of the measurement system and explanation of its mode of work. Experiments were based at two kinds of malfunction possible to be simulated at test bed. First one was simulation of a leak of fuel injection pump, the second one relayed on mounting of sets of injection valves with different nozzles characteristics (spraying nozzle angle), giving different parameters of fuel injection. Presented results of experiment derives from test cycle carried out using laboratory stand of Gdynia Maritime University equipped with 3- cylinder self – ignition engine, powering electric generator.

Schlüsselwörter

  • diagnostics
  • diesel engine
  • torsional vibrations
  • torque and angular speed
Uneingeschränkter Zugang

The Effect of Parameters Burnishing Rolling – Pressuring Process in Aspect to Technological Quality Surface Layer of 316L Stainless Steel

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 75 - 81

Zusammenfassung

Abstract

In the manufacturing of machine elements was important to technological quality products. In surface engineering one of the economic and ecological treatments used for technological properties were burnishing rolling – pressuring process. This is a surface plastic forming a local plastic deformation based on the overall impression given by smooth and hard tool. In production, engineering cylindrical outer surfaces (e.g. plugs propulsion shaft centrifugal pumps seawater) were finishing. You can therefore propose burnishing in exchange for abrasive machining.

The article presents the influence of parameters for burnishing rolling – pressuring process on the degree of relative strain hardening and surface roughness reduction ratio. Burnishing process carried out for 316L stainless steels. After the experimental study, it was determined that there was an increase in hardness and a decrease in roughness of the top outer cylindrical layer of stainless steel, which can be applied to the centrifugal pump shafts ship. Important question to determine in the article of the research was to receive appropriate technological quality. The burnishing due the technological and economic aspect in the production of machine parts in exchange for the abrasive processing can be used. After the experiments, it was found that the technical parameters are influenced by the hardness and the roughness of the outer cylindrical surfaces and the material ratio curve a convex shaped, which, taking into account the load capacity of the surface will be directly affected by its resistance to wear and corrosion of the surface layer.

Schlüsselwörter

  • burnishing process
  • hardness
  • roughness
  • surface layer
  • stainless steel
Uneingeschränkter Zugang

Performance Characteristics of Panel Filters for Internal Combustion Engine Inlet Air Working in a Two-Stage Configuration

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 83 - 94

Zusammenfassung

Abstract

Air filtration conditions in a single-stage and a two-stage filtration system (multicyclone-porous panel filter) are presented. Allowable flow resistance ∆ pfdop values reducing the air filter service life are specified. The benefits of using a multicyclone as a first stage of air filtration, including improved mobility and extended service life, are discussed. Criteria for selecting the filter media for the automobile air intake system using an absorption coefficient of dust km determined at a specific allowable flow resistance ∆pfdop are specified. New methods and conditions to determine the absorption coefficient of dust km for article filter and non-woven fabric filter in a single-stage and a two-stage filtration system are developed and presented. The separation efficiency and separation performance as well as the flow resistance characteristics of the filter set including a single cyclone and a filter element with a specially selected filter medium surface area are tested. Absorption coefficients of dust km for the tested paper filter and non-woven fabric filter were determined for an allowable flow resistance. The effects of dust particle size distribution in the air downstream of the cyclone on reducing the absorption coefficient of dust of the paper filter and non-woven fabric filter in a two-stage filtration system are shown.

Schlüsselwörter

  • two-stage air filter
  • filter medium
  • separation efficiency
  • flow resistance
  • absorption coefficient of dust
Uneingeschränkter Zugang

Monitoring of Rapeseed Oil Fuelled Agricultural Machinery

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 95 - 100

Zusammenfassung

Abstract

Pure plant oil fuels, used in compatible agricultural machinery contribute to sustainable food supply. Especially rapeseed oil fuel significantly reduces greenhouse gas emissions up to 91 % and thus, lowers the carbon footprint of agricultural products. However, despite this advantage plant oil fuels are barely used in practice, because of technical, economical and sustainability concerns of potential users. It is the purpose of this work, to show the reliability, downtimes and the emission behaviour of pure rapeseed oil compatible tractors in practice. As test fuel, cold-pressed rapeseed oil fuel, complying with the national German standard DIN 51605 was used. Emission testing on the tractor test stand is based on the standard procedure of EU guideline 2016/1628. Differing from type approvals, where engine test stands are used, here the measurement is done at the tractors with mounted engines. The power is measured at the power take-off (PTO) with a dynamometer. As testing cycle, the Non-Road-Steady-Cycle (NRSC) and an adapted Non-Road-Transient-Cycle (10sNRTC) are applied. For real driving emission (RDE) measurements, two state-of-the-art tractors are being used. By using a PEMS Semtech Ecostar, which was set up in a box for off-road use, the emission components CO, HC, NOX are measured. Investigation of the monitored 20 tractors (exhaust stages I, II, IIIA, IIIB and IV) for more than 60.000 hours, showed no considerable failures or damages. Generally, the limited exhaust gas components (NOX, CO, HC, PM) determined at a tractor test stand remained nearly at the same level over the operating time. Plant oil tractors with exhaust gas stage IV achieve the legal emission limits with rapeseed oil fuel during both, the NRSC and 10sNRTC. Results of RDE measurements also show that recorded emission values are within expected limiting values for both fuels. Conformity factors that relate actual emissions, measured with PEMS, to corresponding test cycle values, measured at the test stand are within approaching legitimacy.

Schlüsselwörter

  • greenhouse gas emissions
  • liquid biofuel
  • pollution
  • environmental protection
Uneingeschränkter Zugang

The Effect of Adding 2-Ethylhexanol to Jet Fuel on the Performance and Combustion Characteristics of a Miniature Turbojet Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 101 - 109

Zusammenfassung

Abstract

There are currently many studies undergoing in the field of using alternative fuels for supplying different types of propulsion units. The ASTM standard in the aerospace industry, allows using five different technologies of manufacturing synthetic components apart from standard oil-based fuel for the propulsion of turbine engines (as a blend up to 50% with conventional fuel). One of these is a technology associated with the process of converting alcohols (isobutanol) to jet fuel – Alcohol to Jet (ATJ). In the research performance, emission parameters were measured on laboratory test rig with miniature turbojet engine (MiniJETRig). The test rig has been created in Air Force Institute of Technology for research and development works aimed at alternative fuels for aviation. The miniature engine was fuelled with conventional jet fuel – Jet A-1 and blend of Jet A-1 with 2-ethylhexanol. The results for this blend were compared with the results obtained for neat Jet A-1 fuel in terms of different engine operating modes, according to specified methodology. The conducted tests did not show significant differences in engine operating parameters (thrust, fuel consumption and thrust specific fuel consumption) and the values of CO, CO2 and NOx emission indices between the tested fuels. The engine tests took place in similar ambient conditions. Laboratory tests of selected physicochemical properties were also carried out for both fuel samples.

Schlüsselwörter

  • alternative fuels
  • alcohol to jet
  • combustion process
  • miniature jet engine
  • exhaust emission
Uneingeschränkter Zugang

A Concept of the Automatization of Dangerous Driving Manoeuvres

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 111 - 122

Zusammenfassung

Abstract

Automatic control is one of the main characteristic features of the present-day “electrified” motor vehicle. The avoidance of a suddenly appearing obstacle, including a rapid lane-change manoeuvre, is counted among the driving manoeuvres that are most dangerous and difficult to be automatized. Note that this seems to be a fundamental problem for autonomous cars. The authors have shown general vehicle automatization concepts derived from the control systems theory. Against this background, they have presented results of their own analytical studies and simulation research related to the system of automatic controlling of a rapid lane-change manoeuvre. A controller algorithm developed within this work, where a simplified reference model of the lateral dynamics of a motor vehicle was used (transmittance-type model based on well known “bicycle model” but transformed and linearized), was successfully examined in exhaustive simulation tests. The virtual object used for the simulation tests was an extensive simulation model (3D, nonlinear, MBS type) of a two-axle motor truck of medium load capacity, driven with quite a high speed. This detail model had been experimentally verified. In the article, only a fragment of a large research project has been described.

Schlüsselwörter

  • motor vehicle
  • active safety
  • lateral dynamics
  • avoidance automatization
  • obstacle voidance
  • model tests
  • simulation tests
Uneingeschränkter Zugang

Problematics of Modelling Systems for Technical Service of Means of Transport

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 123 - 133

Zusammenfassung

Abstract

Exploitation of means of transport is an important decision issue for transport companies that perform transport tasks. The means of transport during their operation lose their functional properties, which mean that they require technical service and repairs. The components of operating costs of means of transport are expenditures incurred for servicing and expenditures incurred for repairs. As the first cost component increases, the other will decrease and vice versa. We obtain the optimal economic effect of the means of transport when the sum of costs reaches the minimum value. The article presents the problems of optimization of the technical service system. This required identification of technical services and basic parameters characterizing the operation system. On this basis, a mathematical approach to the problem of modelling the maintenance system is presented, including the decision variables, constraints and the criterion function. The identification of the problem of modelling the technical service system is presented in the case study for modelling the technical service of means of transport – buses in the company providing passenger transport services in public transport.

Schlüsselwörter

  • technical service
  • technical service system
  • modelling
Uneingeschränkter Zugang

Expert System Application for Improving the Manufacturing Process for Recreational Watercrafts Modelling Yacht Propulsion

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 135 - 142

Zusammenfassung

Abstract

This article deals with the problems of design improvement and the process of production preparation for recreational watercrafts. An original expert system was created to facilitate the design of mechanical equipment systems and to support the production of pleasure boats. This expert system contains information about issues related to the selection of appropriate mechanical equipment used in modern yachts. An expert system is a computer program, which contains information about a specific and usually narrow field of expertise. With the help of this kind of program, it is possible to solve problems on the same level as a human expert. Like most expert systems, this program is built in such a way that the knowledge base is separated from the rest of the system. It contains two main modules: the knowledge base and the inference mechanism. This system provides conclusions in a descriptive form and in the form of numbers, and presents explanations, diagrams, drawings, photos and videos. What is unique about this expert system is that a user with specialist knowledge in the field of yacht engineering can easily modify the knowledge base. With the development of technology, it is easy to feed new information into the system. This system can become a major tool in design offices and plants producing yachts, because it can be easily expanded and adapted to individual needs.

Schlüsselwörter

  • expert systems
  • yacht propulsion
  • manufacturing of yachts
  • knowledge engineering
Uneingeschränkter Zugang

Conversion of Energy in Electric Drive Supported by the Hydrostatic Drive

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 143 - 150

Zusammenfassung

Abstract

In the article, a study of conversion of energy in a hybrid (electro-hydrostatic) drive of a utility van intended for city traffic is described. In this hybrid drive, the electric drive is periodically accompanied by hydrostatic drive, especially during acceleration and regenerative braking of the vehicle. We present a mathematical model of the hybrid drive as a set of dynamics and regulation equations of the van traveling at a given speed. On this basis, we construct a computer program, which we use to simulate the processes of energy conversion in electro-hydrostatic hybrid drive. The main goal of the numerical simulation is to assess the possibility of reducing energy intensity of the electric drive through such a support of the hydrostatic drive. Our results indicate that it is possible to significantly increase the efficiency of energy conversion in the electric drive by support of the hydrostatic drive. In the article, chosen results of simulation studies for multiple starting and braking the car are given, and they show a 30% decrease for energy drawn by the hybrid drive, compared to solely electric drive.

Schlüsselwörter

  • numerical simulations
  • hybrid drive
  • electric drive
  • hydrostatic drive
  • energy conversion
  • city traffic
Uneingeschränkter Zugang

Selected Aspects of Costs Shaping in the Intermodal Terminal

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 151 - 158

Zusammenfassung

Abstract

The article presents the problems of designing intermodal terminals from the point of view of expenditures on construction and equipment as well as costs of its operation. The scope of factors to be considered at the design stage of the intermodal terminal was determined. The principles of calculation of expenditure on terminal infrastructure are presented. Based on these expenditures, the principles of calculating the cost of maintenance of equipment and labour are outlined. In addition, the practical examples of determining the cost of operation of handling equipment and labour costs are presented. The terminal carries out the functions of transhipment of intermodal transport units between means of transport, belonging to different modes of transport and the operations on these units in connection with their storage. Due to the different types of external means of transport operated in the intermodal terminal, a sufficient number of rail tracks, roads lines, storage, and handling areas should be provided. Apart from expenditures and costs, an important element in the design of an intermodal terminal is its location in the logistics network.

Schlüsselwörter

  • intermodal terminal
  • container
  • TEU
  • costs
Uneingeschränkter Zugang

Energy Consumption Estimation of Non-Pneumatic Tire and Pneumatic Tire During Rolling

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 159 - 168

Zusammenfassung

Abstract

The characteristics of the car tire, and especially its deformation and interaction road, are mainly factors affected the energy consumption of the vehicle and consequently the amount of fuel consumption and emissions to the environment the harmful exhaust gas components. It is estimated that approximately 80-90% of the total energy losses (rolling resistance) are due to internal tire friction, which occurs during its deformation, the remaining 10-20% are ventilation losses, tread face interaction with the road surface and cyclical compression and expansion of air enclosed in the tire. Non-pneumatic tires (NPT) (as a direction of development) are the alternative solutions for conventional tires. Their advantages are as follows maintenance-free and the resistance to typical for pneumatic tires mechanical damages can be a major cause of their widespread use in future (and thus electric) cars. In the available publications, the results of the estimation of the features NPT based on numerical simulations are only presented. There is lack of experimental research results concerning real objects, which determine their driving properties.

Presented work is an attempt to check how the change in wheel structure affects the energy consumption of rolling wheels. Research objects (non-pneumatic tire and pneumatic tire) were selected for the size and destination compatibility. Experimental research were carried out at a universal quasi-static tire testing station, which is located at the Institute of Mechanical Vehicles and Transport at the Department of Mechanical at the Military University of Technology. According to the authors, the obtained results can be an interesting and unique supplement to the problem of assessing the properties of new and future (non-pneumatic tire) construction of vehicle wheels.

Schlüsselwörter

  • non-pneumatic tire (NPT)
  • airless tire
  • resilient tire
  • pneumatic tire
  • special wheel
  • rolling resistance
  • energy consumption during rolling
Uneingeschränkter Zugang

Methods for Determining the Take-off Speed of Launchers for Unmanned Aerial Vehicles

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 169 - 176

Zusammenfassung

Abstract

Unmanned aerial vehicles (UAV) are currently a very rapidly developing type of aviation. The problem of support during the take-off with the use of, i.e. take-off launchers arose along with their development, especially for UAVs with weights and dimensions preventing manual take-off. One of the major issues associated with UAV take-off launchers is for its UAV accelerating element to obtain its initial speed. The article presents three methods of determining launcher take-off speeds for unmanned aerial vehicles, i.e. the concentrated very oblique projection method, the high-speed camera methods, and the acceleration recorder method. The take-off launcher carriage speed in the oblique projection method is determined from a formula. This method involves “ejections” of concentrated masses from the UAV mass range and measuring the component values resulting from the used formula, which contains the range of the oblique projection, the elevation of the projection and its angle. The method using the high-speed camera involves recording the course of ejections of the concentrated mass from the launcher. The average take-off speed is determined on the basis of a take-off run length (section of the launcher race, where the unit accelerates) and defining the start and end frame of the carriage movement. The third method for the determination of the take-off speed utilizes an acceleration recorder. The method with the recorder involves registering a change in the accelerations when the take-off carriage is being accelerated by a system fixed on the carriage or the accelerated object. The article presents the methodology of dynamic tests of object acceleration on a launcher, necessary for the determination of speed with the mentioned methods. Selected results from actual tests with the use of the 01/WS/2015 launcher, which is an element of the ZOCP JET2 set, were presented. The test results are presented in a tabular form. The methods for the determination of the take-off speed were compared on the basis of performed tests. Based on the obtained results, the factors impacting the accuracy of each of the methods were identified.

Schlüsselwörter

  • aviation
  • unmanned aerial vehicle
  • take-off launcher
  • take-off speed
  • acceleration recorder
Uneingeschränkter Zugang

Fatigue Strength Analysis of Welded Aluminium Stairs

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 177 - 184

Zusammenfassung

Abstract

The article presents numerical analyses and results of experimental fatigue tests of the welded stairs made from prefabricated EN-AW 6063-T66 aluminium alloy thin-walled profiles. Fatigue life analysis of welded thin-walled structures is a complicated and demanding task. Fatigue analysis of stairs was carried out according to the concept of a weak link, which was verified experimentally. The FEM method was applied in strength analysis. The conducted research allowed identifying the weak link of the structure at the welded joint. The samples stairs were subjected to fatigue tests. The fatigue tests have been conducted using specially designed set up. The experiments confirmed the numerical analysis. The cracks occurred at welded joints before expected fatigue life to fracture. Then the stairs structure was modified by changing the weld joints arrangement. The fatigue tests were carried out again and showed further weaknesses of their structure cracking of the step profile. To precisely capture this problem, detail finite element calculations for the analysed stairs have been conducted. Applying the nominal stress method, this problem was solved changing the treads profile of the stairs step. The last improvement in the construction was sufficient to satisfy fatigue strength requirement of the analysed structure. The weak link approach and nominal stress method proved to be an effective tool in fatigue analysis of the examined structure.

Schlüsselwörter

  • fatigue tests
  • welded joints
  • aluminium thin-walled constructions
Uneingeschränkter Zugang

Analysis of Possibilities of Increasing a Turbulence by Throttled Axisymmetric Stream for a Fluid Flow Inside Closed Duct

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 185 - 190

Zusammenfassung

Abstract

Fluid flow through the closed duct is a common phenomenon, which is used in many technical applications. A stream of a fluid is often disturbed by different shapes of elements, which have an effect for a flow and causes the growth of a turbulence. Turbulence rising causes an increase of heat transfer process and eliminates areas of flow stagnation in thermal devices. Article presents methodology and results of research about possibilities of turbulence increasing for a fluid flow inside a closed duct. Authors analysed capabilities of application of an internal stream of a fluid in the axis of the tested duct, in the inlet to analysed construction for mainstream turbulence expanding. An additional stream of a fluid was added into the model by internal, partially throttled pipe, which was clogged by special disc. Contact between the disc and internal pipe generated a small gap, where an additional stream of a fluid was directed. Numerical analysis of a level of turbulence for a fluid flow through analysed duct was realized in ANSYS Fluent environment, as an unsteady simulation with Delayed Detached Eddy Dissipation model of turbulence. Experimental research was realized with constant anemometry measurement method. Results of experimental and numerical analysis show, what part of a fluid inside duct disturbed mainstream of a flow.

Schlüsselwörter

  • closed duct
  • turbulence increasing
  • numerical calculations
  • fluent
Uneingeschränkter Zugang

Selection of Turbocharger for the T3.251 Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 191 - 196

Zusammenfassung

Abstract

In this research, a selection of turbocharger for atmospheric engine with automatic ignition T3.251 is described. This experimental engine was designed for driving small tractors. The purpose of turbocharging was to achieve a power of 45 kW. This atmospheric engine at 2250 rpm had power of 35 kW. In the first phase, the initial calculations of the turbocharger parameters were made according to the method proposed be Garret Company. The B65 turbocharger was selected for the study with flue gas exhaust in a multi-variant combination of turbines and compressors. Modifications were made to both turbine and compressor bodies as well as the size of their rotors. Altogether, eleven variants of the B-65 turbocharger were studied. The B65 turbochargers were fitted with an adjustable exhaust valve. By changing the spring preload, the supercharging pressure was adjusted. The research was carried out by performing the external characteristics and load characteristics of the engine under the same operating conditions and settings of the engine and injection equipment. The article presents the co-operation lines of an engine and superchargers using the characteristics of the discussed earlier compressors at Institute of Aviation. The effects of different turbocharger configurations on engine performance, power, fuel consumption, temperature and smoke emissions were also analysed. An analysis of the correct selection of turbochargers was performed.

Schlüsselwörter

  • transport
  • self-ignition engine
  • turbocharging
Uneingeschränkter Zugang

Management of Disused Lead-Acid Batteries in the Context of the Eco-Balance Analysis

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 197 - 203

Zusammenfassung

Abstract

The article describes the results of the eco-balance analysis of the disused lead-acid batteries recycling technology. The analysis will be made using the life cycle assessment (LCA) method. The analysis was developed using the SimaPro7.3.3. software. The life cycle assessment (LCA) was made using Ecological Scarcity and IMPACT2002 + methods. The results are shown as environmental points [Pt], which reflect the potential level of environmental burdens exerted by the analysed object. The results are presented in the environmental categories, which are grouped in the impact categories. For the Ecological Scarcity method, these are emission into air, water, soil, energy, and natural resources and deposited waste. For the IMPACT2002 + method: human health, climate changes, ecosystem quality and resources consumption. The boundaries of the system under investigation include the processes of mechanical battery scrap processing, desulfurization and crystallization processes (PI), the melting processes to obtain crude lead and refining processes (PII and PIII). As the functional unit, there was accepted 1 Mg of the processed battery scrap. Particular attention was paid to the airborne emission, which adversely affect human health and climate change. The technology for which the tests were conducted offers the possibility to recover other elements, for example, secondary lead, polypropylene and sulfuric acid as crystalline sodium sulphate.

Schlüsselwörter

  • recycling
  • Life Cycle Assessment
  • environmental protection
  • lead-acid batteries
  • eco-balance
Uneingeschränkter Zugang

Evaluation of Dynamic Parameters of the Selected Components within Digitally Controlled Hydraulic System

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 205 - 214

Zusammenfassung

Abstract

Dynamic parameters characterizing proportional hydraulic components are essential factors affecting the performance of the construction machinery automatic control system. Knowledge of these parameters is inevitable in modelling the automatically controlled hydraulic power systems as well as designing and analysing the control algorithms. This article presents a methodology of assessing the dynamic parameters of selected components being part of digitally controlled hydraulic power system. The analysed system comprised a typical for mobile hydraulics applications PVG32 proportional directional control valve (DCV) and a variable displacement piston pump. The control system utilised an MC088 PLC controller with specifically prepared and configured software. The measuring system was based on CANbus, which, combined with the PLC used, allowed for flexible configuration of the sensor variables and logging both analogue and digital signals. Among others, the DCV characteristics, the response to step and sinusoidal inputs and DCV hysteresis were examined. The goal was to gather the data required for system modelling and to assess the importance and influence of the investigated parameters onto the model being created.

Schlüsselwörter

  • mobile hydraulics
  • proportional directional control valve
  • hydraulic cylinder control
  • electro-hydraulic pilot valve
  • hydraulic system modelling
Uneingeschränkter Zugang

3D Scanner Working Parameters – Influence on an Accuracy of Mechanical Vehicle Element Reproduction

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 215 - 223

Zusammenfassung

Abstract

In recent years, the reconstruction based on existing physical objects, plays an increasingly important role in research and everyday life. With the advancement of modern industry, more and more often, including automotive industry, modelling and deformation techniques of objects, based on reverse engineering, are used. One of such example is the reproduction of the geometry of motor vehicles using 3D scans. Damages of motor vehicles, cause local changes in the shape of the product and their size and character are directly related to the occurred reaction. However, to assess the damage extent and qualify the object for further repair, it is necessary thoroughly to know the condition of the object after the damage to select the appropriate technology and repair method. This is the case for reverse engineering, and 3D scanning using structural light.

The aim of the study was to evaluate the influence of the parameters of the 3D scanner on the accuracy of reconstructing the geometry of the selected vehicle element – the rear door of the Skoda Octavia in two variants, non-deformed and deformed. The dimensions of door exceeded the range of the largest measuring area of used 3D scanner, so it was necessary to use the photogrammetric technique in order to generate a point model of the object that was used to compose the individual scans.

Measurements were made with different measuring areas: 1000 × 800 × 800 mm, 500 × 400 × 400 mm and 250 × 250 × 200 mm. For the base field, 500 × 400 × 400 mm, several measurements were repeated in order to determine repeatability.

Schlüsselwörter

  • 3D scanning
  • strain identification
  • photogrammetry
  • reverse engineering
Uneingeschränkter Zugang

Experimental Analysis of Noise and Vibration of a Diesel Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 225 - 232

Zusammenfassung

Abstract

Noise and vibration of ignition compression engine is one of the most complicated fields to cope with since every mechanism that compose of the engine affect them separately. In this study, effect of diesel on engine noise and vibration has been studied on an unmodified compression ignition engine. Noise and vibration characteristic of a direct ignition engine, which was fuelled with diesel, were investigated. With the usage of equations obtained from regression analysis, estimation of engine characteristic fuelled with various biodiesels researches were carried out. Tests were conducted at fixed injection timing of diesel fuel. The first system is for diesel fuel injection; the second one is PFI (port-fuelled injection) and is used for injecting alcohol into the engine intake manifold. The engine applied to this study was a naturally aspirated, 3in-line, IVECO AIFO 8031 i06.05 diesel engine with direct injection. Experiments were conducted in a sound insulated room. For each experiment, vibration data gathered from the engine block with 3.2 kHz (for vibration) for 2 s and with 20 kHz sampling frequency for 0.320 s. All measurements were performed under conditions: angle 10; 4 different loads (4, 8, 12 and 20 kW).

Schlüsselwörter

  • biodiesel
  • compression ignition engine
  • engine vibration
  • sound pressure level
Uneingeschränkter Zugang

Maritime Radio Systems for Distress Alerting

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 233 - 240

Zusammenfassung

Abstract

The most important function of a maritime radio communication system called the Global Maritime Distress and Safety System (GMDSS) is the distress alerting function. Distress alerting is the rapid and successful reporting of a distress incident to a unit, which can provide or co-ordinate assistance. This would be a rescue co-ordination centre (RCC) or another ship in the vicinity. The article presents and evaluates the technical and operational possibilities of the maritime radio systems for a distress alerting. Especially the basic functional requirements and regulations for GMDSS referring to the maritime radio systems for distress alerting, resulting from the provisions of the International Convention for the Safety of Life at Sea (SOLAS) and Radio Regulations have been described. The article presents the role of the maritime radio systems for a distress alerting in the shipping and GMDSS as well. A current status and analysis of the systems responsible for distress alerting has been made. In this context, the operation, methods and ranges of transmitting and receiving the distress alerts by the INMARSAT system, COSPAS-SARSAT system and Digital Selective Calling (DSC) system have been described. The article also outlines the future of the maritime radio systems for a distress alerting. In this context, the two projects under the name of „E-navigation” and „The modernization of the GMDSS”, currently being implemented in the framework of the International Maritime Organization (IMO) by the Sub-Committee on Navigation, Communications and Search and Rescue (NCSR), have been presented as well.

Schlüsselwörter

  • communication systems
  • maritime distress communication
  • maritime distress alerting
Uneingeschränkter Zugang

Numerical Studies of Suspension System with Double Spring Loaded Using the Force Pulse

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 241 - 248

Zusammenfassung

Abstract

The forced vibration of a dependent rear suspension model of the two-axle vehicle, equipped with a 3D model of a double spring and a viscous shock absorber is the subject of consideration. The clearance between the master and auxiliary springs is a specificity of the double suspension construction. Dynamic analysis of such a system has been performed by forcing with different forms of force pulses using the fixed base of force 10 kN. Three different time runs (two trapezoidal and one triangular model) are used as the force impulses. Modelling and analysis taking into consideration contact problems have been developed using the MSC.Software package with a special use of Patran pre-processor and Nastran solver. A finite element method (FEM) has been used in numerical analysis of the suspension model with geometric nonlinearities, viscous damping [9] and time-varying load. The boundary conditions of numerical models correspond to a spring support in the real vehicle suspension. The non-periodic damped vibrations and damped free vibrations of the simplified suspension system are investigated during numerical analysis. Selected results of the model tests have been presented in the form of the timings of the accelerations of the spring elements and of the forces in the suspension damper.

Schlüsselwörter

  • dependent motor truck suspension
  • double multi-leaf spring
  • viscous damper
  • numerical analysis
  • FEM
Uneingeschränkter Zugang

The Influence of Changing of Cutting Parameters on Temperature and Cutting Forces During Turning Process by CCET09T302R-MF Insert

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 249 - 256

Zusammenfassung

Abstract

One of the greatest problems of modern production techniques is the achievement of an appropriate quality at minimal costs and accompanied by the production efficiency increase. Therefore, while designing the production process, the technology used should have a considerable influence on the durability and reliability of machine parts to be produced. During finish treatment, the final dimensions as well as functional properties are imparted to a given element by application of proper treatment type. The engineer has a range of production techniques to choose for the proper surface layer formation. It is crucial to find a suitable solution which will meet the requirements as well as the work conditions of a given machine part. The article presents the results of influence of change of cutting parameters on temperature and cutting forces during turning process of stainless steel. A shaft made of 304L stainless steel was used for the research. The cutting process was carried out on a universal CDS 6250 BX-1000 centre lathes. Measurement of cutting forces during turning process used DKM 2010 turning dynamometer. A cutting tool conducted the turning process with CCET09T302R-MF insert by DIJET. During the turning, the following machining parameters were used: cutting speed Vc = 226 m/min, feed f = 0.044; 0.062; 0.083; 0.106 mm/rev and cutting depth ap = 0.375; 0.625; 0.875 mm. The chemical composition of steel was measured by Solaris-ccd plus optical spectrometer. The Smartzoom 5 microscope made the view of the nose radius of cutting tool.

Schlüsselwörter

  • turning dynamometer
  • temperature and cutting forces
  • cutting parameters
  • stainless steel
Uneingeschränkter Zugang

Legal Conditions in the Aspect of Pollutant Emissions from Exhaust Systems of Rail Vehicles Engines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 257 - 264

Zusammenfassung

Abstract

One of the main objectives of the European transport policy is to increase the share of alternative modes of transport – revitalization of rail transport, promotion of water transport and development of intermodal transport, which will help to reduce the dominance of road transport. The adverse impact of transport can be felt both in the natural environment and in society, where the dynamic development of this sector has enabled significant civilization development, with the effects varying depending on the level of economic development, the degree of advancement and use of the various transport sectors, geographical location (including climate), and also the sensitivity of the elements of the environment. Considering contemporary transport hazards, it is important to prevent them from occurring, and when that is not possible – limiting their impact on the environment and reducing the scale and extent of negative impacts. The impact of rail transport on the environment and safety is much lower compared to road transport. The impact of rail transport on the environment mainly comes from the emission of noise and vibration, pollution (from diesel locomotives) and land occupation. The article presents information on the current legal conditions regarding the emission of pollutants from rail vehicles. Information with reference to research tests and emission limit values was included. The subject of tests in real traffic conditions was also mentioned as the direction of changes in vehicle homologation tests.

Schlüsselwörter

  • rail vehicles
  • combustion engines
  • exhaust emission
  • research tests
  • transport
  • environmental protection
Uneingeschränkter Zugang

Studies of Electric Drive with Hydrostatic Support

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 265 - 274

Zusammenfassung

Abstract

In this article, results of experimental studies concerning the relief of a city car electric drive by means of hydrostatic drive support are presented. Experimental studies were performed using a laboratory station built for this particular purpose. Studies of basic properties of elements of hydraulic system and resistances in the mechanical system were performed. The results of experimental studies of a chosen sub-assembly of hydrostatic drive (i.e. hydro-pneumatic battery) are given. The resistances within mechanical system (flywheel) were determined.

In the considered hybrid drive, electric drive is cyclically supported by hydrostatic drive during acceleration or regenerative braking of the vehicle. The results of experimental studies presented in this article were obtained on a designed and built laboratory station representing a model of a lightweight delivery van for city traffic and equipped with the studied hybrid drive. The obtained results suggest that there is a possibility considerably to increase the effectiveness of energy conversion in the electric drive of the vehicle by means of hydrostatic support. By applying the hydrostatic support in the electric drive, the load on the electric battery decreased, which positively influences the length of operation time.

Schlüsselwörter

  • hybrid drive
  • energy consumption
  • energy efficiency
  • regenerative braking
  • city traffic
Uneingeschränkter Zugang

The Evaluation of Viscosity Properties of Engine Oil – Marinol RG 1240 After Working in Various Types of Engines

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 275 - 281

Zusammenfassung

Abstract

The lubricating oils are a liquid substance, consisting of a base (mineral, synthetic or vegetable) and selected additives. They can used for lubricate internal combustion engines, so they called – engine oils. For proper functioning of the engine, lubricating oil have to fulfil basic requirements: the main function is to enable the formation of a film of oil between the moving parts which reduces friction and wear, assisting in cooling, keeping the compression ratio, reducing corrosion, filling in all micro ridges on the surface of cooperating components, sealing the combustion chamber etc. The most significant property of any lubricating oil is viscosity, which is the measure of its resistance to gradual deformation by shear stress or tensile stress. The important feature is that property of viscosity changes during the exploitation process of oil, it may increase and decrease. That is why, for engines it is important not only to choose the type of oil correctly but also to frequent monitor the viscosity. In the article, the author shows how the viscosity of marine engine oils changes after working in different types of engines. The experiments were conducted using the method of the rheometer Haake Mars III of Thermo Scientific. The samples of engine oil – Marinol RG 1240 were collected after various periods of use in three different engine types Cegielski-Sulzer.

Schlüsselwörter

  • engine oil
  • viscosity
  • marine engine
  • lubricating system
  • rheometer
  • Marinol RG 1240
Uneingeschränkter Zugang

Rules for the Organization and Functioning of a Maintenance Support System in a Military Unit – Selected Aspects

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 283 - 288

Zusammenfassung

Abstract

One of the most important tasks of military logistics is to ensure proper use and technical maintenance of armaments and military equipment. Providing maintenance support services on the modern battlefield, with its saturation with complex technical solutions, poses a significant challenge for the logistics system of the Armed Forces of the Republic of Poland. It is the duty of military logistics to adjust the potential of logistical sub-units as well as the organizational scheme and procedures of logistical support in accordance with changes occurring in the field. In times of peace, maintenance support services are focused on preventing equipment malfunctions. If a given piece of equipment becomes non-operational, their task consists in restoring it to full working order, taking into account all economic considerations.

The vehicles should feature good traction characteristics in varied terrain and be adapted to operation in both cold and hot environments. The training of repair sub-unit staff remains an important element affecting the standard of maintenance support.

Schlüsselwörter

  • maintenance support
  • operation
  • technical maintenance
  • automotive vehicle utilization
Uneingeschränkter Zugang

Static Analysis of the Tipper Semi-Trailer Frame

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 289 - 294

Zusammenfassung

Abstract

The article presents a static analysis of the existing three-axle tipper semitrailer using the finite element method. The tipper trailer frame must be strong enough to carry loads from the load while driving, during an accident and especially when emptying the load box when a very large part of the load is pointing at the rear of the frame. Frames are usually made of low-alloy steel with increased strength, most often of grade S355J2G3; duralumin alloy frames are also used.

The currently designed semi-trailer frames are becoming more lightweight while the required load capacity and durability are retained. This is possible thanks to the use of computational methods by the engineers in this finite element method. Static analysis allows for the determination of stress and deformation in the loaded frame and also a possible modification of the frame. The aim of the work was to investigate the influence of the position of the crossbar on the level of stress and deformations for three different load situations of the frame.

Schlüsselwörter

  • static balance
  • global static
  • web local buckling
  • Finite Element Method
Uneingeschränkter Zugang

Analysis of Calculation Models of Scaffolding Constructions in Light of Experimental Tests Results of Constructive Scaffolding Module

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 295 - 306

Zusammenfassung

Abstract

The concern of the article is the analysis of multiple computational models of scaffolding construction, taking into account the experimental results obtained for a representative scaffolding construction module. Analyses of 25 distinct models have been performed, allowing selecting models that most accurately predict deformations of the real construction. The article deals with the issues of elastic-plastic second-order analysis in relation to the working anchored scaffolds and it is focused on the standardization of computational models for engineering calculations. Including in calculations the plastic bearing capacity reserve and using objective calculation procedures, allows optimal designing of the scaffolding and evaluating of the load capacity. Structural model analyses were carried out in terms of their conformity with the actual construction. For comparative purposes, the results of the analyses of individual models were evaluated according to different verification formulas to determine the extent of their applicability. The purpose of the article was to test the behaviour of the system under the influence of constant horizontal forces reflecting the influence of wind and rising from zero until destruction due to the vertical load.

Schlüsselwörter

  • static analyses
  • scaffold structures
  • computational models
  • different verification formulas
  • load evaluating
Uneingeschränkter Zugang

Study on Fuel Injector with Hydraulic Amplifier (HADI) on the Example of Mercedes-Benz Actros Vehicle with Om 471.9 Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 307 - 316

Zusammenfassung

Abstract

One of the recent trends in heavy-duty engines has been the introduction of common rail injector with hydraulic amplifier (HADI − Hydraulically Amplified Diesel Injector) capable of considerable fuel pressure injection increase in reference to fuel pressure prevailing in rail of common rail fuel system. An example of a solution of this type of injectors is the two-valve CRIN4 injectors manufactured by Bosch. They allow the control of the fuel flow rate during injection process and therefore have an impact on the combustion process. In this article, advantages related to their use are described, which allow the engines with such injectors to meet the limits of the admissible content of toxic compounds in the exhaust gases defined in the EURO VI standard. An experimental study of the operation of the Bosch IV generation common rail system was performed on the Mercedes-Benz Actros. During measurement engine load, engine speed, waveforms (electric currents) controlling operation of the selected injectors, fuel pressure in the rail and the control current of high pressure pump control valve (metering unit) were registered. Interpretations of recorded waveforms were made, indicating the areas of application of the various modes operation. The use of CRIN4 injectors for the rapid reduction of fuel pressure in rail was observed, which supports the metering unit (ZME) for pressure control.

Schlüsselwörter

  • diesel engines
  • common rail systems
  • fuel injectors
  • injection rate modulation
  • boot injection
Uneingeschränkter Zugang

Analysis of Influence of the Shape of Cutting Insert on Change of the Parameter Value Describing the Deviation of the Profile of Surface Roughness

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 317 - 323

Zusammenfassung

Abstract

The article presents the influence of the shape of the cutting insert on the surface roughness of the material after medium-fine turning machining. The analysis of measurements of the Ra parameter describing the arithmetic mean deviation of the surface roughness profile from the centre line of the profile by the mechanical and contact method was made using the Hommel Etamic Waveline 20 profile (Gdynia Maritime University). The tests were carried out on three stainless steel X2CrNiMo17-12-2 / 1.4404 shafts with a diameter of 80 mm, subjected to medium-precision turning machining at a length of 270 mm, using three cutting inserts made of tungsten carbide shaped T – triangular, C – rhombic, W – trigonal manufactured by Pafana. Values of used parameters are turning speed Vc = 150 m/min, depth of cut ap = 2 mm and feed f = 0.2 mm/rev. The parameters have been selected according to the manufacturer’s recommendations. The tests were carried out three times, five measurements on the length of the turned part of the rollers. The first test was made after collecting one layer of material, the second test was carried out after collecting five layers of material, and the third test was made after collecting nine layers of material. The article describes the differences between the used tiles and their effect on surface roughness, presents the results of the research, charts of measurements with averaged values and descriptive statistics of the Ra parameter were presented. It was noted that for all measurements of the Ra parameter, the smallest values were obtained using a W-shaped cutting insert. The Ra parameter using the C and T shaped plates increases with each subsequent measurement. The largest value of the Ra parameter is obtained using the T.

Schlüsselwörter

  • surface roughness
  • turning machining
  • cutting insert
  • technological quality
  • contact profilometer
Uneingeschränkter Zugang

The Influence of Electrochemical Battery Aging Process on an Electric Vehicle’s Range

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 325 - 331

Zusammenfassung

Abstract

This article presents the influence of aging processes of the electric vehicle’s electrochemical battery. The increasing number of hybrid and electric vehicles increases the demand for durable and efficient sources of energy storage for vehicles. The vehicle’s declared range is reduced over time.

This is due to the aging of the battery that causes loss of its capacity and loss of its power. To minimize this phenomenon, manufacturers use counteracting solutions that include mounting additional cells in the battery that are switched on when the battery controller identifies a particular battery cell’s failure or high degradation. This is due to the deep and shallow discharges of the battery, the number of charge and discharge cycles, and the age and technology of battery packs.

AMESim software was used for the simulation of the electric vehicle. The research was based on modelling the range of the vehicle whose cell capacity includes processes related to aging of the battery. An aging cell algorithm causes the capacity to drop and consequently reduces the range of one full charge. By modelling aging processes, it is possible to determine the battery’s probable capacity loss during vehicle use and to estimate how these processes affect the vehicle’s range.

Schlüsselwörter

  • battery
  • simulation model
  • electric vehicle
  • LiFePO
Uneingeschränkter Zugang

Jet Aircraft Data Acquisition Systems

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 333 - 338

Zusammenfassung

Abstract

The article presents systems, which record parameters of flight in modern aircraft F-16, which was delivered to Polish Airforce in 2006. With the current level of technical development of the aviation industry, data acquisition systems are an important element of all aircrafts. These systems are responsible for the flight safety, allow reading and storing the most important flight parameters, and combined with digital control and safety systems allow to counteract dangerous situations, which especially can happen often in the case of military aircraft such as the F-16 due to their combat purpose. Systems records basics parameters of plane and engine, as specific fuel consumption or height of flight provides video and audio recording, and aerial combat assistance. These systems record even failures of a braking system during landing. Thanks to modern technology, and devices like those described in this article, F-16 is one of the best fighters in the world. The amount of data provided by analogue and digital sensors is so large that it requires the partitioning of parameters and use of several basic recorders of the entire system is the unit called DAU, or Data Acquisition Unit, which records the most important flight parameters, such as flight time, engine speed, or altitude.

Schlüsselwörter

  • aircraft
  • safety
  • jet engine
  • aviation
Uneingeschränkter Zugang

Study of The Influences of Blending Different Proportions of Propane into Methane on Combustion Characteristics at the Knock Threshold by Using RCM

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 339 - 346

Zusammenfassung

Abstract

A spark-ignited Rapid Compression Machine (RCM) has been used to investigate the influences of the different proportions of methane-propane mixtures on the combustion characteristics at knock threshold operating condition. First, the threshold operating points of the mixtures have been obtained and the results indicated that the piston driving pressure reduces from 142 bars to 90 bars as the propane content in the mixture increases. As a spark plug was fitted in this RCM, the optimum spark timing was also investigated. It was established that spark timing should be set synchronize with the piston at TDC, due to the free movement of the piston. In most RCMs, piston can move toward TDC following the equilibria of forces due to the absence of con-rod. Finally, knock intensity of the different mixtures has been studied. Pre-heating system in RCM with and without trace heating system; effects of flow-rate and lambda variations on peak pressure, ignition delay time and ARR; threshold operating conditions of pure methane, 90% methane and 10% propane, 80% methane and 20% propane, 70% methane and 30% propane; effect of driving pressure on the knocking intensity for mixture of methane and propane for heavy and light knockings are presented in the article.

Schlüsselwörter

  • Rapid Compression Machine
  • knock threshold operating condition
  • peak driving pressure
  • knock intensity
Uneingeschränkter Zugang

Gurney Flap and T-Strip Alternatives in Application to Typical Aircraft Steer Surface

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 347 - 354

Zusammenfassung

Abstract

Classic Gurney flap and double Gurney flap (called T-strip) are well-researched trailing edge modifications used in aerospace engineering. However, one of the inevitable effects of their use is the aerodynamic drag increase at low lift conditions, concerned as the major drawback of these solutions. This article presents Gurney flap and T-strip passive alternatives, which guarantee similar advantages in terms of e.g. lift enhancement, but without significant drag increase. Their aerodynamic analysis was performed on the application case of a typical symmetrical aircraft stabilizer with movable steer. Both solutions, consisting of plates nearly parallel to the direction of flow, were modelled as two-dimensional cases and CFD calculations were performed for specified range of angles of attack and steer deflections. Obtained aerodynamic characteristics allowed assessing the influence of selected modifications on the stabilizer effectiveness, as well as on hinge moment characteristics. The flow pattern changes in the presence of analysed devices were also investigated. In this way, performed analysis provided valuable information about the advantages and disadvantages of using of such devices in comparison to classic Gurney Flap and double Gurney flap. The results showed that using proposed solutions gives the possibility of significant reduction of the aerodynamic drag of the whole stabilizer at low lift conditions, while still maintaining favourable lift characteristics.

Schlüsselwörter

  • CFD
  • steer
  • stabilizer
  • Gurney flap
  • T-strip
Uneingeschränkter Zugang

Impact of the Driver Behaviour on the Energy Recuperation in an Electric Vehicle

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 355 - 362

Zusammenfassung

Abstract

In recent years, energy recuperation systems have been used more and more often. This is due to the rapid development of electric and hybrid cars. In view of the growing technology that allows for a recuperation system efficiency increase, it is important to consider whether the weakest link is in this case not the driver and his ability to customize the driving style to the needs of energy recovery. This article attempts to answer this question. For that purpose, the special road tests were conducted in a real urban traffic. Two drivers were involved, each of whom used alternating recovery and non-recovery driving style. In total twelve road tests, realisations have been completed. The results of the measurements were entered into a mathematical model that simulated the work of the energy recuperation system. It allowed estimating how different recovery systems can work in the conditions of conducted tests. On this basis, an analysis was made both in terms of the total amount of energy that can be recovered in the case of recuperative and non-recuperative driving, and analysis of the recuperation system working and the real impact of the driver’s driving style on the energy stored in the car’s battery. Basis on the conducted considerations authors noted that use of recuperative driving technique could increase the amount of stored braking energy on average by 60%. It was also seen a significant impact on the energy waveform in the battery.

Schlüsselwörter

  • energy recuperation
  • driver behaviour
  • braking energy
  • mathematical model
Uneingeschränkter Zugang

Simulation Investigation of Operational Conditions of Rotor for High-Speed Compound Helicopter

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 363 - 370

Zusammenfassung

Abstract

The article presents results of simulations concerning possibilities of rotorcraft performance enhancements for compound helicopters with introduced additional wings and propellers. The simple model of helicopter including a point mass of fuselage and a rotor treated as a disk was used for calculations of helicopter flight equilibrium conditions. For the defined flight states, the more detailed model of elastic blade was applied to compute magnitude of rotor loads and level of blade deformations. The model of elastic blade includes out-of-plane bending, in plane bending, and torsion effects due to variable aerodynamic and inertial loads of rotor blades. Equations of motion of rotor blades are solved applying Runge-Kutta method. Taking into account Galerkin method, parameters of blade motion are computed as a combination of assumed torsion and bending Eigen modes of the rotor blade. The six-bladed rotor with stiff connections of blades and hub was applied for comparison of flight envelope for conventional helicopter and versions of compound rotorcraft with additional propellers and with wings and propellers. Simulations indicate that, in the case of compound helicopter configuration, achieving the operational flight conditions at high speed of 400 km/h is possible without generating excessive loads and blade deformations. The results of calculations of rotor loads and generated blade deflections are presented in form of time-run plots and as rotor disk distributions, which depend on radial and azimuthal positions of blade elements. The simulation investigation may help to define demands for rotor of high-speed helicopter.

Schlüsselwörter

  • compound helicopter
  • rotor loads
  • blade deformation
Uneingeschränkter Zugang

Robust Optical Flow Estimation Applied to Particle Image Velocimetry Images for High Resolution Velocity Measurements

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 371 - 377

Zusammenfassung

Abstract

The article discusses application of Robust Optical Flow Estimation for increasing of Particle Image Velocimetry measurement resolution. Nowadays, one of the promising approaches for increasing the performance of the PIV systems is application of the Optical Flow Estimation for image analysis. Nevertheless, some of the OF implementations do not perform well in case of motion discontinues typically occurring in the PIV images. The purpose of this study is to validate the performance of the Robust Optical Flow Estimation. The tests were performed on simulated images of vortex flow and the results were compared with displacement fields calculated with the typical correlation PIV algorithm. The velocity for high and medium particle concentration was similar for Optical Flow and PIV-like analysis. Furthermore, the performance of the robust optical flow framework was tested with images corrupted with blurs and occlusions. The tests proved good performance of proposed analysis in case of non-Gaussian sources of measurement errors. The robust estimation framework performed well in the case of common image artefacts and proved to be a promising method for precise PIV flow measurements. The presented approach can be useful in development hybrid OF-PIV post processing software aimed for high-resolution measurements and provide a help in designing of experimental investigation of microscale fluid flow phenomena.

Schlüsselwörter

  • Particle Image Velocimetry
  • optical flow estimation
  • particle image density
  • image occlusions
Uneingeschränkter Zugang

Influence of Thermal Signal Characteristics on Defect Detection in GFRP by Active Optical Thermography

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 379 - 383

Zusammenfassung

Abstract

Advances in technological development, since the 1990s, has been associated with the development of two basic domains of knowledge: information technology and material engineering. The development of material engineering is directly related to composite materials. One group of composite materials are fibre-reinforced composites. Due to their unique properties, they are used in various fields of engineering sectors. Composites reinforced with glass fibre (GFRP) are the second most commonly used composite after carbon fibre reinforced composites (CFRP). GFRP in many cases can replace traditional structural materials, which are usually made from metal. Of course, this material is exposed to damage both in production and operation phases. One method of non-destructive testing that effectively identifies defects in GFRP is active optical thermography. In this method, for thermal stimulation of the tested material, various types of heat sources are used for example: heating lamps, lasers etc. This article analyses the influence of the characteristics of the thermal optical sources on detection of typical defects in GFRP.

Schlüsselwörter

  • non-destructive testing
  • composite material
  • IR thermography
Uneingeschränkter Zugang

Use of Biofuels in a Compression-Ignition Engine – Comprehensive Technical and Economical Analysis

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 385 - 393

Zusammenfassung

Abstract

The assessment of renewable fuels on the basis of the results of internal combustion engine’s tests is not clearly good or not good. Biofuels can be a part of sustainability from energy sources, energy security and energy diversity point of view. But they cannot be assessed better compared to the fossil diesel as for their combustion and air pollution and the engine’s external parameters. Comparison test series has been conducted with three different fuel and their controlled blends. These fuels were fossil diesel, the conventional, standardized biodiesel, and a new type biodiesel, which is the so-called TBK-biodiesel. These tests covered the physicochemical properties of the fuels, the engine external parameters, the combustion parameters and the exhaust emission of an internal combustion compression ignition engine. Furthermore, external costs have been calculated based on the emission results. Physicochemical properties, engine parameters, combustion parameters, exhaust emission and external costs have been observed as parameter groups, which contain many parameters. A complex evaluation could be built with the help of such kind of parameter set. On the basis of the results, it can be established that almost in the most cases the direction of the parameters’ changes is negative. Thus, the evaluation’s centre of gravity has been observed as shifted in the negative direction.

Schlüsselwörter

  • conventional biodiesel
  • TBK-Biodiesel
  • complex evaluation
  • Diesel engine
  • combustion
  • emission
Uneingeschränkter Zugang

Exhaust Emission Estimation in Freight Transport Systems

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 395 - 406

Zusammenfassung

Abstract

Modelling of transport systems is a complex issue requiring taking into account many factors that allow for the mapping of the real system and thus allowing decision support. In the era of increasingly higher requirements for services, transport also faces the challenges of sustainable development. Therefore, it is necessary to conduct research both in the sphere of technical and organizational solutions aimed at limiting pollutant emissions. Mapping in the model the negative impact of transport on the environment allows for planning the implementation of the transport service taking into account the pro-ecological criterion. This is particularly important in urban areas where traffic and especially heavy goods vehicles are particularly onerous for inhabitants and require limiting transport work in the city area and the use of environmentally friendly rolling stock. The aim of the article is to present the considerations regarding the modelling of transport systems including pollutant emissions. The article introduces the problem of cargo distribution and a review of the models of estimation of pollution emission in the micro and macro scale was carried out. Next, a mathematical model was proposed which is a variant of the Vehicle Routing Problem of the so-called Green VRP. In the distribution model was used COPERT methodology for estimation of harmful substance emission. In article examples of calculations carried out on the example of the city of Warsaw for the organization of cargo distribution due to the CO emission criterion was presented. The article ended with a short synthesis of the work carried out.

Schlüsselwörter

  • transport
  • freight transport
  • modelling
  • emission estimation
  • COPERT
  • Green VRP
Uneingeschränkter Zugang

Effective Harvesting of Braking Energy in Electric Cars

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 407 - 422

Zusammenfassung

Abstract

Regenerative braking and damping are effective approaches for electric cars to extend their driving range. A disk Faraday generator regenerative braking strategy integrated with controlled charging of a supercapacitor is developed in this article to advance the level of energy-savings on the car board. The kinetic energy of the car suspension during driving regenerated effectively to electric energy by using shock absorber is harvested and then used to charge the vehicle’s battery, the power electronics and the supercapacitor. One of the advantages of supercapacitors is their high power capability, which is applicable for high rate of charging and discharging operations like motor starting and regenerative braking of an electric vehicle. This article presents a new charging method for supercapacitors. Common for regenerative braking and damping chargers for supercapacitors are usually equipped with electronic PWM converter performing two states of operation per switching cycle. A simple open-loop control system is applicable for the whole charging state. The proposed circuit consists of a minimum number of components. It is free of stability problem and protects itself from being overloaded by supercapacitor with zero initial charge. Simulation results for regenerative braking processes corresponding to three velocity tests are included.

Schlüsselwörter

  • urban transport
  • environmental protection
  • electric cars
  • energy harvesting
  • braking energy recovering
  • damping energy recovering
  • supercapacitors
  • simulation
Uneingeschränkter Zugang

The Errors of the Numerical Calculations of Dynamic Characteristics of Cantilever Beam Mounted on the Plate

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 433 - 440

Zusammenfassung

Abstract

The safety, comfort of the crews, stability, economics of the equipment when ship operating is the leading requirement in the field of designing and manufacturing marine structure and machinery. As a result, all parts of the ships must be tested and inspected to meet the basic safety requirements of the shipping association. The design, manufacture, testing in the maritime field in general and shipbuilding sector in particular are expensive, time consuming: such as aerodynamic experiments of the engine, collision test, ship manoeuvring, vibration test and balance of deck beams, hull beams, hatch covers, shafts...thus experimental works are sometimes impossible. Along with the development of computer science, many numerical models and software programs have been developed to solve these difficult problems. There are many numerical modelling methods, starting with the finite difference method, the boundary element method, the finite element method, the no mesh method, the weight residue or the energy method. The Work will be limited to the analysis of the most popular numerical modelling method - finite element method using Patran and Nastran software. In the first step of our research, T-beam was analysed as a part of ship hull structure (thin-walled structure). The article goes into the analysis of the accuracy of selected numerical models for the natural vibration frequency of the T-beams mounted on the plate. After modelling, calculating the natural frequency of the T-beam using the Patran - Nastran software, the results were compared with the theoretical values. From that, we evaluate the dispersion and error of different numerical models and select the optimal numerical model. Optimal model will be used for modelling full ship hull with superstructure.

Schlüsselwörter

  • T-Beam
  • vibration
  • ship structure
  • modal analysis
  • FEM errors
Uneingeschränkter Zugang

Optimization of Gassing-Up Operation Based on Comparative Analysis of Two Twin Ethylene Carriers

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 441 - 446

Zusammenfassung

Abstract

The article consists comparative analysis of the gassing-up operation – purging cargo tanks with cargo vapour, on gas carriers carrying primarily Ethylene – one of the most expensive cargo of all hydrocarbons carrying by the sea. The source of the problem constitutes similar densities of both gases under specific conditions – Ethylene and Nitrogen – a gas that tanks are purged before gassing-up. The analysis is made for considerable optimization of the process. The comparison of gassing-up methods is based on tests and measurements on two particular twin gas carriers. In both cases different methods – parallel and cascade were chosen to do the gassing-up (parallel means to purge tanks separately at the same time, cascade means to purge tanks one after the other) what allows specifying beneficial procedure. What was estimated during voyages were technical parameters measured during gassing-up, time of the process and the most important information – loss of the cargo. Analysis of particular stages of the operation also allows estimate the level of gas mixing in the tank. The basic purpose of this profile, based on Ethylene loss, is selecting alternative for carrying this operation in more efficient way, what constitutes determining the most proper method of gassing-up – parallel or cascade and setting temperatures, pressures, mass flows which minimize vapour of Ethylene vented to the atmosphere.

Schlüsselwörter

  • gassing-up
  • gas mixing
  • ethylene
  • nitrogen
Uneingeschränkter Zugang

Car Tyres with Reduced Energy Consumption

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 447 - 456

Zusammenfassung

Abstract

The objective of this publication is to present the changes that are currently made to the tyre structure in order to reduce its rolling resistance including the rubber compound, tread pattern and tyre support structure. Based on a broad literature review the authors present a history of changes introduced in the construction of tyres aimed at reducing their share in the energy losses needed to overcome the resistance of rolling wheels in the car’s movement (at present it reaches even 50%). They indicate a significant conflict resulting from the rubber properties using the data sets available on the labels of summer and winter tyres in which the improvement of wheel adhesion leads to increased rolling resistance. In the next part, the basic factors determining the rolling resistance of tyres are approximated, focusing on those related to their construction. The influence of the rubber loss factor is described which values at different deformation frequency (turning the wheel 101-102 Hz and its braking at 104-105 Hz). It determines the interaction of the rubber with the road surface. Various ways of actions are shown to reduce the losses occurring during the deformation of the tyre: the use of silica as a rubber filler and the introduction of nanotechnology to control the rubber crosslinking process, reducing the volume of rubber used to build the tyre coating, simplifying the tread pattern and changing the tyre diameter size to a larger one (treatment used in electric cars). Particular attention was also paid to the weakness of the changes, i.e. the increase of the noise generated by the more elastic coating of the tyre and the possible directions of counteracting this phenomenon were signalled.

Schlüsselwörter

  • energy consumption
  • rolling resistance
  • tyre construction
  • tyre tread rubber
  • tread pattern
Uneingeschränkter Zugang

The Influence of the Compression Ratio Error and the Pressure Error at the Beginning of Compression on the Heat Release Characteristic Calculated Based on Indicator Diagram Marine Diesel Engine

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 457 - 463

Zusammenfassung

Abstract

In the operational diagnostic of marine engines, the analysis of indicator diagrams is important. In addition to analysing changes in the values of indicated parameters, should be aimed to oriented broader analysis, including the determination on the basis of experimental indicator diagram of heat release characteristics during the combustion process.

In the diagnostics of piston engines, including marine engines, special interest arouses to use single-zone model based on indicator diagrams as a source of information. There are calculated heat release characteristics: net heat release (Q) and intensity of heat release (q).

The article discusses the impact problem the characteristics of heat release calculated based on experimental indicator diagram various errors – the compression ratio error and the pressure error at the beginning of compression.

Based on the results of own research we analysed the impact on the characteristics of heat release the compression ratio error and the pressure error at the beginning of compression.

The effect of the errors on the course of characteristics q and Q, to the typical marine medium speed engine Sulzer A25/30 and low speed engine Sulzer RTA 76 shown.

Schlüsselwörter

  • marine diesel engine
  • indicated parameters
  • indicator diagram
  • heat release characteristics
  • compression ratio
  • compression pressure
Uneingeschränkter Zugang

Material Recovery as an Opportunity of Immediate Introduction of Eco-Friendly Transport System (Vehicles)

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 465 - 474

Zusammenfassung

Abstract

The article presents an analysis of the need to introduce pro-ecological solutions at the fuel sector of industry, resulting from dynamic economic development, and environment protection requirements. The forecasts on the number of vehicles in the world and the subsequent growth of interest in alternative fuels are presented. The advantages of using these fuels as compared to petroleum fuels and electricity are described. The presented analysis emphasizes the context of EU legislation on environmental requirements. At the same time, it was pointed out the need to obtain the required technical and energy characteristics of alternative fuels, the competitive costs of their production, and important environmental aspects. Taking into account these premises and the principle of circular economy closed circuit, alternative fuels from organic waste, in particular from enormous amounts of organic non-biodegradable wastes (packaging, multi-material fabric, rubber, tires) were proposed. It has been shown that thermal decomposition by thermolysis, described briefly in the article, can be a method suitable for a wide economic application within the alternative fuel production system. Based on literature data and own experience, it has been found that the quality of fuels (oil, gas) obtained from the thermal decomposition of organic and mixed waste is not different from the requirements for the best quality raw materials used in the production of petrol and may even exceed the properties of petroleum. Introduction of the system of regional production and distribution of alternative fuels from waste could be remarkable driver of small towns and rural areas revitalization and development, while supporting build up and improvement of local communities.

Schlüsselwörter

  • road transport
  • material recovery
  • environmental protection
  • thermolysis
  • alternative fuels
Uneingeschränkter Zugang

Analysis of Damage of the Cooling Aggregate in Vehicle with Cold Storage Chamber

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 475 - 482

Zusammenfassung

Abstract

Vehicles with cold storage chambers realize the transport of fast spoil articles. The cooling system of such chamber is its critical subsystem, the essential component of which is a cooling aggregate driven by vehicle combustion engine via belt transmission. The main assembly of the analysed aggregate was the axial five-piston compressor. Small aluminum pistons were led in cylinders in fixed head made of aluminum alloy. Such pistons were driven through steel tappets, mating through their spherical surfaces with spherical seats made in small pistons. Through their front surfaces, placed opposite to the spherical surfaces, the spatial disc cam made of aluminum alloy drove small pistons. The cam was mounted on the steel shaft. The co-operation of described parts was in presence of refrigerant oil. The abrasive and fatigue wear of elements occurred. Because of long-term utilizing of the aggregate the damage of radial sealing ring occurred. Then, external impurities of high hardness got into the contact zone between the mating surfaces. The main aim of the study was to analyse consequences of such fact. The failure was noticed in the form of wear of disc cam, front surfaces of tappets, and the plastic deformation in the spherical surfaces of the seats. Then, due to deformation and the displacements of the rotating shaft, wear of the side surface of disc cam during contacts with small pistons surfaces took place. Moreover, we noticed wear of the side surfaces of the pistons and the cylinders mating with them in the fixed head. In the article, we present figures of damaged surfaces of elements and results of the SEM analysis of spherical surfaces of tappets. The material transfer occurred between the spherical surfaces of tappets and their seats.

Schlüsselwörter

  • cooling aggregate
  • combustion engine
  • sealing ring damage
  • failure
  • blurring
Uneingeschränkter Zugang

Results of the Crash Tests of Electric Cars

Online veröffentlicht: 11 Nov 2019
Seitenbereich: 483 - 490

Zusammenfassung

Abstract

The work presents the results of crash tests carried out with six electrical car models (from 2012-2013), with the weight of 1200-2300 kg (Smart Electric Driver, Mitsubishi IMiEV, Nissan Leaf, CODA, Ford Focus BEV, Tesla Model S). The results were published on the Internet by the National Highway Traffic Safety Administration (USA), and the tests involved a car travelling at the speed of 56 km/h, hitting frontally into a non-deformable (stiff) barrier, positioned perpendicularly to the car’s direction of movement. Particular attention was paid to the deformation of the car after hitting the barrier, so-called stiffness characteristics of the frontal crumple zone, and to the loads on the dummies placed at the driver’s and passenger’s seat (Hybrid III, a 50-centile man and a 5-centile woman). Results of the tests with electric cars were compared with the results of the tests with over a hundred of combustion engine cars with similar weight and type of car body (sedan, hatchback). The tests proved that, in the majority of electrical cars tested, the deformation of the frontal crumple zone after hitting an obstacle is larger than in case of similar cars with internal combustion engine. Because of that, the dynamic loads on the occupants of the vehicle tend to be smaller, as indicated by measured loads on the heads and chests of the dummies. The results may suggest that the frontal crumple zone may be better constructed in the case of electric cars, while the design possibilities regarding that area are limited in standard cars due to the combustion engine, which is not deformed during the accident, which makes it more difficult for the energy of the crash to dissipate.

Schlüsselwörter

  • road transport
  • vehicle safety
  • crash tests
  • safety of passengers
  • electric vehicles

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