A study of low-comression-ratio dimethyl ether diesel engines

Abstract

Abstract

A new concept of using dimethyl ether (DME) as an alternative fuel in direct injection compression ignition engines with low compression ratios was presented to seek a combustion regime with the highest thermal efficiency. The concept was experimentally evaluated by a comparison of performance and emissions between a DME-fuelled engine and the corresponding conventional diesel engine. The result demonstrated that the DME-fuelled engine is superior to the conventional diesel engine in terms of thermal efficiency, emissions and engine noise, particularly at low compression ratios. However, NO_x emission is unacceptably high and needs to be reduced by exhaust gas recirculation (EGR) or after-treatment systems.