Potential Analysis of a DMC/MeFo Mixture in a 4-Cylinder Light Vehicle Gasoline Engine

Parallel to investigations with a fuel mixture of dimethyl carbonate (DMC and methyl formate (MeFo) on a single-cylinder-research-engine, a 4-cylinder light vehicle gasoline engine was operated with the same synthetic substitute for gasoline. When produced with renewable energy the fuel is CO2-neutral and offers the potential to reduce emissions. The results of the 4-cylinder engine operation confirmed the expectations. With minor adjustments to the engine control unit (ECU), a brake thermal efficiency gain of 16 % was achieved at the lowend-torque operating point while the particulate emissions were reduced by 99 % during static operation. The physical properties of DMC/MeFo help to lower the cylinder charge temperature, enabling a stoichiometric operation over the entire engine map. Investigations in homologation relevant driving cycles result in a particulate number reduction of up to 90 %, while CH4 and CO are reduced by 46 % and 84 %. The results gained from this study show the potential of oxygenated, CO2-neutral fuels when used as a substitute for fossil fuel for modern gasoline engines in order to reach the climate targets with lowest local pollutant emissions.