Experimental and Numerical Identification and Optimization of eFuel Potentials on Combustion Behavior and Engine Efficiency

Abstract:

The demand for CO₂ reduction is rising sharply nowadays， especially for gasoline engines. Considering a life cycle analysis， the energy carrier， i.e. the fossil fuel is responsible for the emissions problem. The defossilization towards synthetic fuels from renewable energy sources （eFuels）， can make the combustion engine almost CO₂ neutral. The design of an eFuel composition and properties is crucial， as its formulation influences the gasoline engine processes and efficiency. From injection， mixture formation and combustion to post-oxidation and exhaust after treatment， a change in fuel composition has significant effects. For these reasons， several research projects were conducted as part of a collaboration between Dr. Ing. h.c. F. Porsche AG and FKFS. Measurements of a single-cylinder engine test bench and of a spray test ring with different fuels were produced and used to calibrate 3D-CFD simulation models.The fuel formulation， mixture formation and combustion behavior were analyzed deeply， with the aim of increasing engine efficiency while improving emissions. A virtual optimization of the engine configuration was possible in addition to single-cylinder engine tests， leading to significant potentials through alternative fuels and engine optimization.

Key words:gasoline engine;eFuel;CO₂ reduction;engine efficiency