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研究了柱塞直径、喷嘴形式、供油提前角、喷嘴伸入汽缸长度、喷油压力、进气涡流比等燃烧系统主要参数对发动机性能的影响，测录了示功图和喷油器针阀升程以及污染物排放，计算了发动机的燃烧特性，并与发动机燃用柴油时进行了对比．发动机性能研究表明：与柴油相比，二甲醚能够提高发动机的热效率，降低ＮＯｘ 排放，实现无烟燃烧．燃烧特性分析结果表明：二甲醚的喷油延迟角大于柴油的喷油延迟角；二甲醚的滞燃期比柴油短，预混燃烧量少，扩散燃烧速度比柴油快．
The influence of the main parameters of the combustion system, such as plunger diameter, nozzle form, feed advance angle, nozzle extension into cylinder length, injection pressure and intake vortex ratio, on engine performance was investigated. The dynamometer and injector needle Valve lift and pollutant emissions, the engine combustion characteristics were calculated and compared with the diesel engine fuel. Engine performance studies show that DME can improve engine thermal efficiency, reduce NOx emissions and achieve smokeless combustion compared with diesel. The results of combustion analysis show that the retardation angle of DME is larger than that of diesel fuel. DME has shorter retarding period than diesel fuel, less premixed combustion volume and faster diffusion combustion rate than diesel fuel.