汽油机进气歧管数值计算方法研究

针对两种数值计算方法（四口全通、三闭一通）影响进气歧管的流场特性和进气均匀性计算结果的问题，分别采用这两种数值计算方法对某四缸汽油机的两款进气歧管进行了CFD计算，分析了两种数值方法获得的进气阻力和进气均匀性计算结果。同时，建立了相应的发动机试验白架，通过分析两款进气歧管对发动机的动力性、经济性及运行平稳性的试验数据来验证数值计算方法的可靠性。研究结果表明：采用“四口全通”和“三三闭一通”这两种数值计算方法获得的进气阻力变化趋势一致，两者都适用于进气阻力仿真分析；两种数值计算方法的进气均匀性计算结果差异很大；“三闭一通”数值计算方法更加适用于进气歧管进气均匀性分析。

Numerical computed methods for intake manifolds in gasoline engine

Aiming at the effect of the results of two methods on flow field characteristics and air inlet uniformity of the intake manifold, two numerical calculation methods were used to simulate two models of intake manifold of a four-cylinder gasoline engine. Meanwhile, an engine test bench was established to verify the reliability of two numerical calculation methods on engine performance, fuel economy and running sta- bilily. The results indicate that the using ＂four all-pass＂ and the ＂three close＂ of these two kinds of numerical computing methodsfor air in- take resistance change trend is consistent, both are suitable for air intake resistance simulation analysis ; the results of air inlet uniformity vary widely;the ＂three close,one pass＂ numerical calculation method is more suitable intake manifold air intake uniformity analysis.