高压喷射乙二醇双燃料发动机的燃烧与排放特性研究

In order to improve the engine's power performance and reduce pollutant emissions,the effects of different high-pressure injection of ethylene glycol(EGP5,EGP10,EGP20)on the engine's combustion and emission characteristics under different substitution rates(EG0,EG5,EG10,EG15)were studied on an inline 4-cylinder turbocharged common rail diesel engine.The research results show that under the same ethylene glycol injection pressure(EGP),the peak pressure and peak heat release rate in the cylinder show a trend of first decreasing and then increasing with the increase of ethylene glycol substitution rate;As the injection pressure of ethylene glycol increases,the average temperature in the cylinder also increases,and the ignition delay period remains basically unchanged.The combustion duration is slightly shortened,and NOx emissions decrease with the increase of substitution rate.The weighted average particle size of ultrafine particles shows a trend of first increasing and then decreasing;At the same substitution rate,with the increase of EGP,the peak pressure in the cylinder slightly decreases,while the effective thermal efficiency increases,and the average effective thermal efficiency of EGP20 is 1.6%higher than that of EG5.In summary,when the injection pressure of ethylene glycol is 20MPa,it can effectively balance the combustion and emission performance of the engine.