内燃机进排气系统的数值模拟

随着排放法规的日趋严格和能源的日益紧缺，发动机燃烧过程的优化显得尤为重要。文章利用GT-Power软件建立了某发动机工作过程的仿真模型，应用总变差减少的有限体积法（FVM—TVD）对该发动机的进排气系统进行数值模拟，包括进排气管内流体流速随曲轴转角变化的情况，以及进排气管内的压力波动情况。计算结果表明，动态效应对进排气管内的宏观气流运动有较大的影响。在压力波动和脉动效应等因素的作用下，进排气管内流体的流速和流量均呈波动状变化。

Numerical Simulation of Internal Combustion Engine Intake and Exhaust System

With increasingly strict emission regulation and energy shortage, the optimization of engine combustion process is becoming more important. The simulated model of an engine operating process was built based on GT-Power. Finite Volume Method-Total Variable Diminish （FVM-TVD） was applied to simulate the intake and exhaust systems which included the transformation of the fluid velocity and the dynamic pressure at different positions in the intake and exhaust pipes with the transformation of crank angle. The calculation results show that the dynamic effect has greatly influence on the macro-flow movement of the intake and exhaust pipes. The fluid velocity and flux change as fluctuations under the influence of dynamic pressure and ripple effect.