内燃机缸内几种湍流流动涡粘度模型的比较

On New Eddy Viscosity Models of Turbulent Flow in the Cylinder of Internal Combustion Engine

将几种湍流涡粘度模型 ,即压缩修正的 k-ε模型、RNG- k-ε模型和修正的非线性三方程模型用于计算内燃机缸内的湍流流动 ;对计算结果进行了分析 ,并与实验数据作了对比。结果表明 :RNG- k-ε湍流模型的计算结果较 k-ε模型有所改进 ,而修正的非线性三方程模型则克服了涡粘度模型不能反映平顶活塞压缩上止点处雷诺应力各向异性的缺点 ,在定量和定性上明显优于各种 k-ε模型。

A new modified k-ε model and RNG-k-ε model with a compressible term and nonlinear three-equation model are applied to simulating in-cylinder turbulent flow in internal combustion engines.Comparisons among numerical data of the above models are made,indicating each one's advantages and deficiencies as well as its applicability.The results show that RNG-k-ε model is not only more accurate in predication in turbulent flow than the traditional k-ε model but also can be applied to simulating rotational flow,and that the modified nonlinear three-equation model overcomes the defect that all models in the category of EVM are not able to predict anisotropy at TDC of compression stroke of the internal combustion engine with flat face pistons.