多缸汽油机气缸压力的缸间差异研究

Study on Differences of Cylinder-to-Cylinder Pressure in Multi-Cylinder Gasoline Engine

首先分析了多缸汽油机缸间差异的产生原因并提出了评价多缸发动机缸间差异的指标。其次介绍了同时测量四缸汽油机各缸气缸压力的试验装置。最后对平均指示压力、最高压力、最大压力升高率的偏差率δpi、δpm 、δDpm 和其偏差率绝对值的缸间均值бpi、бpm 、бDpm 进行了统计分析。结果表明 :多缸汽油机各气缸的压力存在较大差异 ;δpi、δpm 、δDpm 的变化范围大约在± 5 %、± 30 %、± 4 5 %之内 ,бpi、бpm 、бDpm 的范围大约为 0～ 9%、0～ 2 1%和 0～ 4 3%。

Firstly,the causes of differences of cylinder-to-cylinder were analyzed in multi-cylinder gasoline engine,and the evaluating parameter on the differences of cylinder-to-cylinder pressure was proposed.Secondly,the testing device was introduced for simultaneously measuring cylinder pressure.And finally,the statistical analysis of deflective rates of the indicated mean effective pressure,the peak cylinder pressure and the maximum rate of cylinder pressure,and the absolute value of their deflective rates were conducted.The results showed that there existed a large difference of cylinder-to-cylinder pressure in multi-cylinder gasoline engine while the value of deflective rates of the indicated mean effective pressure,the peak cylinder pressure and the maximum rate of cylinder pressure were about ±5%,±30% and ±45%,and the absolute value of their deflective rates were about 0～9%,0～21% and 0～43% respectively.