汽油机进气歧管流通性和均匀性数值模拟

进气歧管的流通性和均匀性对发动机性能产生重要影响.建立了某四缸汽油发动机的GT-power仿真模型，对进气歧管的气体流速进行了仿真计算；利用STAR-CD软件模拟计算了进气歧管不同进气角度时各支管内的气体压力和流速分布，分析了各支管的进气均匀性和充气系数.计算和分析结果表明，通过改变进气口方向和稳压腔容积等几何参数，可以提高进气歧管的气体流通性，改善进气歧管各支管内气体流动质量，使各支管内气体流量趋于均匀.计算结果为该进气歧管的改性设计提供了理论依据.

Numerical simulation of liquidity and uniformity of gasoline engine intake manifold

The liquidity and uniformity of intake manifold have a major impact on engine performance. A four-cylinder gasoline engine model was created by GT-power and the gas flow rate of intake manifold was simulated. Gas pressure and velocity distribution were showed in different inlet angles though STAR-CD and the intake uniformity and inflatable coefficient were analyzed in each of the branched pipe. The results show that the gas liquidity and the gas flow quality in branched pipe were improved by changing the air inlet direction and regulator chamber volume and other geometric parameters, which made the gas flow tended to be uniform in each pipe. The calculation results provide a theoretical basis for designing the intake manifold modified.