二甲醚发动机性能试验研究

Experimental Study on the Performance of Dimethyl Ether Engine

对柴油机燃用二甲醚(DME),在各种技术条件下的发动机排放性能、动力性和经济性进行了试验研究.结果表明,燃用二甲醚时,发动机碳烟排放很低,但在大负荷工况下,由于燃烧不好,CO和HC的排放较高.采用进气增压技术,有利于改善燃烧,降低排放和能量消耗率.采用废气再循环(EGR)技术可以有效地降低NOx排放,但在大负荷和过高的废气再循环率情况下,会使燃烧恶化.进气增压和适度的废气再循环率相结合,可以同时降低排放和改善能量消耗率,有利于达到超低排放的要求.

The experimental studies on diesel engine fueled with dimethyl ether(DME)were conducted in the aspects of exhaust emissions, power and energy consumption. The results show that DME engine smoke emissions are very low. However, at the high load condition, the CO and HC emissions are very high due to the fuel/air mixing worsening. Supercharging can improve combustion, exhaust emissions and energy consumption of DME engine. Exhaust gas recirculation (EGR) can reduce NOx emission obviously, but at the high load and high EGR rate conditions, the combustion will be worsen. The combination of supercharging and EGR is beneficial to meet ultra-low emission regulation for the DME engine.