发动机内部EGR建模与仿真分析

The Modeling and Simulation Analysis of Internal EGR Engine

在内燃机中,废气残留比例直接影响气缸内气体的燃烧状态,进而影响发动机的排放、动力性和经济性。可变气门正时技术(VVT)可通过调整气门开闭时间实现气缸内的废气再循环(内部EGR),从而控制燃烧气体内的废气比例。分析了气门的结构、物理过程以及气门处的气体流动过程,建立了不同气门开闭时刻对应的废气残留比例动态模型,并搭建仿真模型,分析各个物理参量间的关系,最后通过实验验证了模型的合理性。

In the internal combustion engine,the rate of the residual exhaust gas directly affects the cylinder combustion state,thereby affects engine emissions,power and economy.By adjusting the valve opening and closing time,VVT achieves the exhaust gas recirculation,and controls the ratio of the exhaust gas.This paper analyzes the structure of the valve,physical processes and gas flow at the valve.Through the valve opening and closing time,this paper establishments the residual gas dynamic model.Then this paper builds the simulation models and analyzes the relationship between the various physical parameters.Finally,the experimental data verifies that the model is reasonable.