直喷式柴油机燃用二甲基醚(DME)试验研究

介绍了在1100单缸直喷式柴油机上燃用DME的发动机试验研究结果。研究表明：通过增加循环供油量可使柴油机燃用DME后恢复到原机略低，同时缸内最大爆发压力降低，发动机碳烟排放为零，HC和CO排放比原机略高，NOx排放比原柴油机降低约50%以上，供油提前角减少，缺内最大爆发压力降低，NOx排放可进一步大幅度降低，但HC排放略有升高；加大喷孔直径，缸内爆发压力升高，NOx排放升高，HC和CO排放在中低负荷相差不大，但在大负荷工况有所升高。

Experimental Investigation on Burning Dimethyl Ether (DME) in Direct Injection Diesel Engine

This paper introduces the experiment on a single cylinder direct injection diesel fuelled with Dimethyl Ether (DME).The results show that the power of the engine fuelled with DME equals to that of the original engine by enlarging the cycle fuel,and the torque of the DME engine was larger than that of a diesel engine at a middle and low rotate speed,but smaller in high speed.Compared with the original diesel engine,the ignition delay was smaller,and the largest heat release rate was much lower,it will result in a much lower maximum cylinder pressure.Also,NO x emissions reduced more than 50%,HC and CO emissions increased slightly and the engine was free smoke emissions on burning DME.With the delaying of the injection time,the cylinder pressure will decrease,NO x emissions will be reduced also,but the HC and CO emissions will be increased.By enlarging the orifice diameter,the maximum pressure in the cylinder of DME engine will increase,and the combustion duration will decrease,it is an effective way to reduce the fuel consumption.However,it will result in the increase of NO x emissions,and HC and CO emissions will increase under a high load.