<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>For the development of gas exchange for large diesel engines, a compromise has to be found between efficient valve-flow and the time between overhauls. On the one hand, large effective flow areas, especially during valve-overlap, are demanded. On the other hand, there are limitations of cylinder bore regarding the maximum diameter of inlet and outlet valves and the minimum distance (dead space) between valves and piston, as well as wear-related smaller seat angles. For large medium-speed diesel engines, a valve-seat angle of <italic>β</italic> = 30° for inlet and outlet valves is a standard application. For engine-operation with clean fuels, a valve-seat lubrication (gasoil) or smaller seat angles (natural gas) need to be applied. With this presentation, the basic influence of different valve-seat angles on the operation values and emissions will be considered for the example of the single-cylinder research engine FM16/24. Using a self-developed testbed, experimental investigations into effective flow areas as a function of valve-lift at inlet and outlet valves have to be executed. With this input, different cycle calculations including T/C have to be carried out to determine deviances in specific fuel-oil consumption, exhaust-gas temperatures, NOx emissions and air/fuel ratio. The results will be discussed critically.</p>
</abstract>

For the development of gas exchange for large diesel engines, a compromise has to be found between efficient valve-flow and the time between overhauls. On the one hand, large effective flow areas, especially during valve-overlap, are demanded. On the other hand, there are limitations of cylinder bore regarding the maximum diameter of inlet and outlet valves and the minimum distance (dead space) between valves and piston, as well as wear-related smaller seat angles. For large medium-speed diesel engines, a valve-seat angle of β = 30° for inlet and outlet valves is a standard application. For engine-operation with clean fuels, a valve-seat lubrication (gasoil) or smaller seat angles (natural gas) need to be applied. With this presentation, the basic influence of different valve-seat angles on the operation values and emissions will be considered for the example of the single-cylinder research engine FM16/24. Using a self-developed testbed, experimental investigations into effective flow areas as a function of valve-lift at inlet and outlet valves have to be executed. With this input, different cycle calculations including T/C have to be carried out to determine deviances in specific fuel-oil consumption, exhaust-gas temperatures, NOx emissions and air/fuel ratio. The results will be discussed critically.

Influence of Valve-Seat Angles to Operation Values and Emissions of Medium-Speed Diesel Engines

leander.marquardt@hochschule-stralsund.de

niklas.kockskaemper@hochschule-stralsund.de

Acta Mechanica et Automatica

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

For the development of gas exchange for large diesel engines, a compromise has to be found between efficient valve-flow and the time between overhauls. On the...

Influence of Valve-Seat Angles to Operation Values and Emissions of Medium-Speed Diesel Engines

Published Online: Mar 19, 2023

Page range: 173 - 179

Received: Sep 14, 2022

Accepted: Dec 11, 2022

DOI: https://doi.org/10.2478/ama-2023-0019

Keywords
medium-speed engine, gas exchange, valve-seat angle, flow coefficient, thermal load

© 2023 Leander Marquardt et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Influence of Valve-Seat Angles to Operation Values and Emissions of Medium-Speed Diesel Engines

Published Online: Mar 19, 2023

Page range: 173 - 179

Received: Sep 14, 2022

Accepted: Dec 11, 2022

DOI: https://doi.org/10.2478/ama-2023-0019

Keywordsmedium-speed engine, gas exchange, valve-seat angle, flow coefficient, thermal load

© 2023 Leander Marquardt et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
medium-speed engine, gas exchange, valve-seat angle, flow coefficient, thermal load