The effects of dimethyl ether enriched air (DMEA) on exhaust pollutants and performance characteristics of an old generation diesel engine

Abstract

In this study, the effect of dimethyl ether enriched air (DMEA) on pollutants and performance characteristics a diesel engine was evaluated. The combustion parameters have been evaluated by simulation method. Simulation results show that the in-cylinder pressure increases slightly while the combustion duration is shorter for DMEA-engine compared to the original case. In addition, a comparative test on DMEA-engine was carried out, in which DME was supplied into the intake manifold at a constant concentration to the mass of intake air. The results show that, when operating with DMEA, the brake specific energy consumption (BSEC) reduces slightly at full load condition by 2.20%. While, at a speed of 1600 rpm, the BSEC increases from 2.6% to 7.7% at low load and slides from 3.1% to 5.5% at high load condition. The smoke level reduces moderately when the test engine operating with DMEA by 6.25% on average at full load and 2.0% to 8.2% as load increases at intermediate speed condition. The CO emission reduces 5.28% while NOx and HC emission increase 5.62% and 7.1% on average at full load condition. At the speed of 1600 rpm, CO reduces 5.9% while NOx and HC increase by 7.1% and 27.5% on average.