【摘要】 在一台车用多缸直喷柴油机上进行了燃用二甲醚的试验研究.结果表明:增大每循环的供油量可使二甲醚发动机的额定转矩超出原柴油机的额定转矩;采用流通截面积较大的喷油器,增加喷油器伸出气缸盖底平面的距离,降低启喷压力,可以提高二甲醚发动机的热效率;与柴油机相比,燃用二甲醚时发动机在全部转速和负荷范围内都可以实现无烟燃烧,且NOx排放下降50%左右,CO和HC排放与柴油机相当.将性能优化后的二甲醚发动机装车进行行驶试验,该车的最高时速(120km/h)和加速性能都达到了原柴油车的水平.试验表明,二甲醚是一种可以替代柴油的理想清洁燃料.更多还原

【Abstract】 Experiments were carried out to investigate performance of a multi-cylinder direct-injection diesel engine with dimethyl ether (DME) as fuel. The results show that maximum torque of DME engine can exceed that of diesel engine by increasing fuel supply amount per cycle. Increasing the flowing area of nozzle orifices or the vertical distance of the nozzle tip into the cylinder and reducing opening pressure of nozzle can improve the thermal efficiency of DME engine. NOx emission of DME engine is about 50% of that of diesel engine. Smokeless emission can be realized in all operating conditions. HC and CO emissions are close to those of diesel engine. DME engine modified with the above optimum data was mounted onto the vehicle and tested on the road . The maximum speed (120 km/h) and the accelerating performance of this vehicle can reach or exceed those of the corresponding diesel vehicle. Experiments confirm that DME is a kind of ideal alternative fuel for diesel engines.更多还原