显式代数雷诺应力模型在超声速/高超声速流场计算中的应用

Research of Explicit Algebraic Reynolds Stress Model in Supersonic/Hypersonic Flow Field Computation

为了提高显式代数雷诺应力模型在高超声速流场中的计算精度,以修正后的CG k-ε模型作为湍流时间尺度决定方程,将Wallin和Johansson显式代数雷诺应力模型(WJ2000模型)应用于超声速/高超声速流场数值计算,并与线性湍流模型的计算结果进行了对比分析。结果表明WJ2000模型对高超声速压缩拐角附近壁面压力和热流分布的预测要优于线性湍流模型,同时网格依赖性明显低于后者;对CG k-ε湍流时间尺度决定方程所做修正不影响WJ2000模型对超声速流场的预测结果,但使其对高超声速流场的预测精度明显提高。

In order to improve explicit algebraic Reynolds stress model in hypersonic flow field calculation accuracy,taking the modified CG k-ε model as the determining equation of turbulent time scale,this study applied the Wallin & Johansson explicit algebraic Reynolds stress model in supersonic/hypersonic flow field computation and compared the results with those of linear turbulent models. It can be concluded that the prediction of WJ2000 model on wall pressure and heat flux distribution near the compression corner is apparently better than that of linear turbulent models,and the grid dependence is obviously lower than the latter. The modified determining equation of CG k-ε turbulent time scaling shows no influence on the WJ2000's prediction on supersonic flow field,however,the accuracy of its prediction on hypersonic flow field has been significantly improved.