Evaluation of Different Gasoline Formulations on a High-Performance Engine 2023-24-0038

The future of the combustion engine will to some extent depend on the use of CO₂-neutral eFuels to avoid further fossil CO₂ emissions. Also, the use of synthetic fuels offers the possibility to improve various engine properties, such as thermodynamics, EGR compatibility or emissions, through targeted influence on specific fuel properties. To this end, a methodology was generated to attribute various engine effects to particular fuel properties. Therefore, the Chair of Combustion Engines (LVAS) at the TU Dresden developed a fully automated testbed for motorcycle engines, including clutch and gear switching mechanisms. Hitherto, emissions measurements for motorcycles were done mostly on chassis dynamometers, with the disadvantage of a large spread of results. Due to the lack of consistency the analysis of fuel properties was not possible. To prove the developed methodology, a test campaign including 15 different gasoline fuels was elaborated in cooperation with KTM R&D GmbH. Before measuring over 200 WTMC cycles on this new engine test stand, a fast conditioning system was devised for the coolant, engine oil and catalyst. This allows for cycle times of just over an hour with subsequent cold start. The experiments demonstrate the detailed effects of the fuel on engine behaviour. The highly dynamic engine test stand showed a much better reproducibility and a massively decreased test interval, compared to the conventional dyno testing. During the evaluation of engine measurement data, differences between fuels were established regarding various characteristics. These include starting behaviour, CO₂ emissions and fuel consumption in correlation with varying C-H-O ratios, CO and NO_x as well as particle emissions. Recommendations for future engine application and adaptation for synthetic fuels can be drawn from the findings.