In the field of shipping, renewable fuels are becoming increasingly important. Their expanded use helps to significantly reduce CO₂ and pollutant emissions, thereby supporting the transition toward more sustainable and climate-friendly maritime mobility.
Against this background, new technical requirements are emerging for the long-term efficient operation of marine combustion engines. The use of alternative fuels requires comprehensive modifications to the overall system. The collaborative research project Fuel-OptimOT, funded by the German Federal Ministry for Economic Affairs and Energy, addresses exactly this issue and aims to examine the tribological behavior of the power unit in greater detail and to develop reliable models for predicting system behavior. Oil transport into the combustion chamber when using alternative fuels plays a central role in this context.
The shipping industry is facing the challenge of increasingly stringent emission targets set by the International Maritime Organization (IMO), requiring a greater use of low-emission or zero-emission fuels by 2030. These include, in particular, renewable methanol, dimethyl ether, and ammonia, which are expected to play a key role in the future maritime energy mix.
In light of these challenges, a medium-speed marine test engine with methanol intake manifold injection and pilot ignition is being investigated. The engine is equipped with extensive instrumentation on the piston, liner, and exhaust side. The focus lies on analysing oil transport within the system, especially processes influenced by ring motion, and their impact on ignition and combustion phenomena. The aim is to gain a deeper understanding of these interactions and to optimize them in a targeted manner in order to increase power density, particularly at high mean effective pressures and engine speeds.
Building on this, the present collaborative project focuses on the detailed analysis and model-based representation of the complex processes within the piston tribological system, consisting of the piston, piston rings, and cylinder liner.
The aim of the project is to provide a more comprehensive description of the tribological behaviour of the power unit and to develop reliable predictions of system behaviour. A particular focus is placed on oil transport into the combustion chamber when using alternative fuels.
To this end, the Institute of Internal Combustion Engines and Fuel Cells is developing a numerical simulation model for a dual-fuel engine operated with methanol and n-heptane. This model is intended to enable the representation of ignition processes, particularly in the piston top land region. The goal is to predict the key operating parameters of such an engine with a deviation of no more than ±5%.
At the same time, the predictive accuracy for ignition phenomena in the piston top land area is to be significantly improved in order to ensure a reliable representation of real operating conditions within the combustion chamber.
