高超声速二方程湍流模型的数值模拟对比

对基于Reynolds和Favré(密度加权)混合平均的二方程湍流模型进行了修正,同时根据数值模拟高超声速流动时必须具有高分辨率捕捉间断面与在边界层内抑制数值粘性的能力的要求,提出了新的总变差减小(TVD)格式熵修正函数.在此基础上,通过对压缩拐角的高超声速湍流的数值模拟,对基于Reynolds和Favré混合平均的二方程湍流模型,以及其它不可压缩模型及可压缩性修正模型进行了对比,显示了不同湍流模型及可压缩性修正在计算壁面压力分布和热流分布上的特点,说明了对高超声速压缩拐角型流动,湍流模型可压缩修正的必要性,得到了基于Reynolds和Favré混合平均的二方程湍流模型的计算结果最接近实验结果. 

Comparison of two-equation turbulent models for hypersonic flow simulations

A two-equation turbulent model based on the mixed Reynolds and Favré (density weighted) average was modified for hypersonic compressible turbulence. In order to suppress the influences of the numerical viscosity toward the boundary layer, and yet to maintain simultaneously the high resolution on capturing the disco ntinuities in the hypersonic flow field, a new entropy correction function was proposed for the total variation diminishing (TVD) scheme. A test case on hypersonic flows over a ramp was then computed using the modified mixed averaged model, as well as the incompressible models proposed by the others together with their respective compressibility correction models. The comparative study shows that the compressibility corrections to the two-equation turbulence models are necessary for hypersonic ramp-type flows, and the numerical results by the modified mixed averaged model are closest to the experiments simultaneously.