根据排气压力波确定发动机排气顺序的研究

根据柴油机气缸排气时歧管内总压和静压关系,提出采用排气压力波上的最小幅度静压脉冲识别发动机排气顺序的方法;建立4缸和6缸柴油机的仿真模型并对排气歧管内的压力波动进行仿真。仿真结果表明,发动机气缸排气时,与该气缸相连的排气歧管内产生的静压脉冲幅度低于其他气缸在该歧管所产生的静压脉冲幅度。在4缸柴油机上测量了4个歧管内的压力波,试验结果表明,4个压力传感器所测的最小幅度的静压脉冲时间顺序与柴油机发火顺序一致,根据第1或4缸所测的静压脉冲幅度可判断出排气顺序。

Confirmation of the Exhaust Sequence of the Diesel Engine Based on the Exhaust Pressure Wave

A method to recognize the exhaust sequence of the diesel engine utilizing the minimum static pressure of exhaust pressure wave is proposed based on the relationship of the overall pressure and static pressure in the manifold while cylinder is exhausting. The simulation models of 4-cylinder and 6-cylinder diesel engines are established with the simulation of the pressure fluctuation in exhaust manifold subsequently. The results indicate that the static pressure peak in the exhaust manifold is obviously lower than the value of other cylinders when the cylinder is exhausting. Pressure wave in 4 manifolds in 4-cylinder diesel engine are measured with experimental data from 4 pressure sensors, which shows that time sequence of the minimum static pressure is in accord with the firing order. Therefore the exhaust sequence could be judged according to the static pressure range of the 1 st or 4 th cylinder.