The Experimental Study Of A Single Cylinder Direct Injection Diesel Engine Fueled With Dimethyl Ether

This dissertation investigates the performance and emissions characteristics for both Dimethyl Ether (DME) and diesel fueled direct injection diesel engine.The theoretical study of the working process of DME engine are also carried out. The main achievements are as follows:1 It's for the first time to extensively investigate effects of main combustion system parameters such as plunger diameter, plunger stroke, fuel delivery advanced angle, valve opening pressure of nozzle on performance of DME engine.The parameters are optimized.2 The load characteristics tests and exhaust emissions measurements of the engine are done at the original fuel delivery advanced angle and modified fuel delivery advanced angles when run on pure DME and different fuel blends consisting of predominant DME and some diesel fuel in the diesel engine stage experiments.3 The performances and emissions characteristics for both Dimethyl Ether (DME) and diesel fueled direct injection diesel engine are investigateddeeply and completely.The experimental results show that in the power and torque of dimethyl ether fueled ZS195 diesel engine is better than the archetypal one. In the full load range, the engine exhaust contains no smoke and the NOx exhaust obviously decreases and the engine noise also decreases.The different fuel blends consisting of predorminant DME and some diesel can conqer or in large part improve the wear and leakage of plunger.4 According to the study of combustion characteristics of DME engine, it is for the first time to find that the injection delay of DME is longer than that of disel. Investigation results show that DME engine has shorter ignition delay, lower peak pressure, lower maximum rate of pressure rise.The investigation demonstrates that the DME is an attractive fuel for diesel engine to achieve high effeciecy, ultra low emissions.