供油系统对二甲醚发动机燃烧循环变动的影响

Effect of Fuel Supply System on Cyclical Combustion Variation of DME Engine

摘要:

通过采集分析二甲醚发动机示功图,试验研究了喷射系统参数和低压供油系统参数对二甲醚发动机燃烧循环变动的影响。结果表明：增大喷孔直径可以减小燃烧循环变动，高速时喷孔直径对燃烧循环变动的影响较低速时更显著；增大喷油器的开启压力，低速时燃烧循环变动增大，高速时则反之；发动机负荷增加，燃烧循环变动减弱；供油提前角从BTDC 6°CA提前到BTDC 13°CA后，燃烧循环变动系数呈先增大后减小的趋势；增加低压供油系统储能器的体积可以有效控制燃烧循环变动。

Abstract:

The indicator diagram was collected to study the effect of injector parameters and low pressure fuel supply system on cyclical combustion variation of DME as engine. The experimental results showed that the cyclical combustion variation of the DME engine decreased when the nozzle diameter hole diameter was increased. The influence of the nozzle hole on the cyclical combustion variation for the DME engine at high speed was more significant than that of low speed. The cyclical combustion variation increased when the opening pressure of the oil injector was increased at low speed, however it showed the opposite changing trend at high speed. The cyclical combustion variation decreased when the load of the engine was increased. The cyclical combustion variation coefficient showed a trend of first increase and then decrease when the fuel supply advance angle was advanced from BTDC 6°CA to BTDC 13°CA. The cyclical combustion variation could be controlled effectively by adding the volume of the accumulator of the low pressure fuel supply system.