Volume 214 (2018): Edizione 3 (September 2018)

There are a lot of energy saving devices for ships on the market, but few have seen wide adoption on naval ships, with one exception: the bulbous bow. The bulbous bow was developed for naval ships in the early 20^th century and is now widespread on a variety of ship designs. Many have wondered if the effect of the bulbous bow — reducing the resistance of a ship by reducing the bow wave — could be replicated somehow at the stern — by reducing the stern wave. This is exactly what is done by a novel and patented energy saving device called Hull Vane^®.

Invented by Dutch hydrodynamicist Dr Peter van Oossanen for an America’s Cup sailing yacht in the early 21^st century, research over the years has shown that this wing-shaped appendage works best on ships that combine a relatively high displacement with a relatively high top speed requirement — even if most sailing hours are done at half speed. Examples are certain offshore vessels, superyachts, patrol vessels and naval ships. On offshore patrol vessels, the resistance reduction from the Hull Vane^® ranges typically from 10 to 20% over the entire useful speed range.

In this paper, the working principles of the Hull Vane^® will be described to give a better under-standing of the device. An overview will be given of the work carried out on naval ships and coastguard ships (25 to 142 m), based on Computational Fluid Dynamics studies, model tests and full-scale applications. The question ‘Why?’ will be answered by translating the hydrodynamic effects to concrete capability improvements for naval ships: a lower fuel consumption, a longer range, reduced signature, a higher top speed and improved seakeeping.

The question ‘When?’ will zoom in on whether a Hull Vane^® is something to be included in a newbuild or if it is something to be retrofitted to an existing ship. Finally the answer to the question ‘How?’ will explain the process of either integrating a Hull Vane^® in a newbuild project or retrofitting it during a midlife upgrade of an existing ship.

The paper presents based on literature critical evaluation of commonly known methods for determining the mechanical losses of a piston engine. Their advantages and disadvantages were pointed out also the possibility of their use in a marine propulsion system was assessed.

In the paper, there has been constructed such a non-classical Bittner operational calculus model, in which the derivative is understood as a central difference D_n{x(k)}:= {x(k+n)–x(k-n)}. The discussed model has been generalized by considering the operation D_n,b{x(k)}:= {x(k+n)–bx(k-n)}, where b∈𝕔\{0}. In the D₁-difference model exponential-trigonometric and hyperbolic Fibonacci sequences have been introduced.

The aim of the article was to present selected methods for the production of layered composites in the aspect of the additive in the form of polyester-glass recyclate. The polyester-glass recyclate was obtained from the original composite material from which the ship’s hull was made in Poland in the 1980s. The article presents the technology of processing polyester-glass waste in order to obtain recyclate. The methods of manual lamination, vacuum bag method and vacuum infusion were described successively. The advantages and disadvantages of particular technologies have been presented in terms of the possibility of their use in the production of polyester-glass recycled composites. From the described and verified technologies, the vacuum bag method can be the most advantageous for composites with recyclate.

In this paper radio link system solutions operating in 300 MHz — 3000 MHz range and sea environment were described. Solutions with more than one frequency and wave propagation models for horizontal not more than 50 km and far range were described. In the paper the results of actions taken design and construction solutions adopted were presented, aimed to contribute to ensure the reliability of the system, among other things, by implementing mechanisms for collecting and processing information. This solutions allow resources management to automatically adjust the transmission parameters configuration to the bitrate and range requirements. Available configurations can be extended with active part and electronic beam steering with one or more beams. The paper describes antenna systems ability of transmission parameters adaptation to get the range required.

Increasing security in Polish maritime areas is not only a priority for maritime administration, but all users of this zone. The article proves the general assumptions of the implementation of the National Maritime Safety System as well and the method of implementation of its individual elements. Detailed system information was included PHI-CS and Information Exchange System and Sailing Safety. An attempt was made to investigate the scope of modernization of the System of Information and Navigation Safety System. The article describes elements: the national Safe Sea Net system, rules of passenger registration, databases, ICT connections.

The article presents the analysis of the threats to ships of the Polish Navy resulting from the implementation systems of active neutralization for missiles of MANPADS (e.g. Grom, Igla, Mistral) to the armed forces of the Russian Federation.

The paper describes the most popular sea anti-aircraft missile sets based on MANPADS missiles and the capabilities of Russian multi-sensor systems for protection of Vitebsk class helicopters and aircraft (President-S). The article contains conclusions from the analysis of the capabilities of weapon systems and active disruption systems in the confrontation of a present ship with a modern combat helicopter and proposals for solving this problem by means of the diversification of missile of anti-aircraft systems.

This article is an attempt to interest the subjects associated with maritime technology — in the possibilities of increasing the safety of Polish Navy ships (or civilian ships), which may be threatened by attacks of maneuvering missiles and drones moving at low altitude at high speed. The concept proposed by the team was initially verified in simulation tests and the obtained results of these studies indicate that the automated missile self-defence system based on guided and unguided missiles with caliber 40 mm and 70 mm, can be an effective means of self-defence (even the smallest vessels). Small dimensions and mass as well as simplicity of use and reliability of this weapon system allow to believe that 40 mm MLRS¹ could also be used by special forces of Polish Navy in offensive operations (destruction of lightly armoured objects of surface or ground, vehicles, force, putting smoke screens, mine mines) to 2000 m. For that reason, the system is referred to by the team of implementers as ‘pocket rocket artillery’.