SST二方程湍流模型在高超声速绕流中的可压缩修正

为模拟高速可压缩湍流问题，对剪应力输运（SST）湍流模型进行了可压缩修正。数值格式采用改进的总变差减小（TVD）格式，并对湍流模型的负值强制项进行了隠式处理。在此基础上计算了绕平板以及基本无分离和具有分离流动结构的压缩拐角的高超声速流动。计算结果和实验数据及半经验公式的对比表明：SST湍流模型的可压缩影响项为密度加权脉动速度的平均与压力梯度的标量乘积。经可压缩修正后的SST湍流模型与原模型及其它可压缩修正模型相比，所计算的壁面压力、摩擦阻力和壁面热流分布具有更高的精度。

Compressibility Correction for the SST Two Equation Turbulence Model in Hypersonic Flows

A compressibility correction for the shear stress transport (SST) model suitable for hypersonic compressible turbutent flows is proposed in this paper. Numerical computations are performed by using an improved TVD scheme, and the negative part of the source terms in the turbulence model is discretized by using an implicit scheme. To validate the corrected model, hypersonic flows over a flatplate, as well as compression ramps with or without separated flows are computed by using the developed model. The numerical results reveal that, in comparison with experimental results and results computed by the original model and semi\|empirical formulae, the compressibility effects on the SST model stem from the scalar product of the weighted density average of the turbulent fluctuating velocity and the pressure gradient of the average flow field. In addition, it is demonstrated that the presently established model provides more favorable results on the wall pressure, skin friction and wall heating rate distribution for the experiments than the original SST model and other compressibility modifications.