应用不同湍流模型计算叶栅流场的结果与比较

采用有限体积TVD-LW格式求解N-S方程,使用了B-L模型、高雷诺数k-ε模型和低雷诺数k-ε模型等多种湍流模型。并且用具体算例说明本文所用程序的可靠性,比较了3种的湍流模型的特点。B-L模型最大的优点是简单、使用方便。k-ε方程适应性强,分为低雷诺数k-ε方程和高雷诺数k-ε方程两种。高雷诺数k-ε方程比低雷诺数k-ε方程精度略低,但所需计算时间和存储量都比后者小,网格也可以粗些。k-ε模型对粘性层、分离区有比较高的分辨能力,高雷诺数k-ε模型比较适于一般数值计算。 

Numerical Simulation of Cascades with Different Turbulence Models

The finite-volume TVD-LW N-S solvers were developed by using B-Lmodel of high Re number k-ε model and low Re number k-ε model respectively.Some numerical examples have been calculated to demonstrate the resolving capability of the numerical method for boundary layer,separative region and shock.The advantage of B-L model is simplicity and convenience.The k-ε model has high adaptability,and can be divided to two types.One is low Re number k-ε model, for which the wall function is not used;and the other is high Re number k-ε model,for which the wall function is used.The precision of the low Re number k-ε model is better than that of high Re number k-ε model,but it requires more computer time,storage capacity,and larger grid.The k-ε model can predict boundary separation.For convectional calculation,high Re number k-ε model is more suitable as it can provide required precision with coarser grid.