Spalart-Allmaras湍流模型在高超声速气动加热计算中的应用

Application of the Spalart-Allmaras Turbulence Model in Hypersonic Aerothermodynamics Computations

将AUSM+格式与LU SGS隐式迭代相结合,采用一方程的Spalart Allmaras湍流模型和二阶迎风MUSCL格式,研究了火星"探路者号"实验模型在10马赫来流条件下的气动热问题。采用量热完全和热完全两种气体模型的计算结果与实验数据进行了比较。热完全气体模型模拟的热流分布规律与实验吻合较好,但是对分离区的热流估计过高。在网格合理划分,尤其是满足近壁面的网格分辨率要求的前提下,该方法能够合理反映高超声速流场除分离区以外的气动热特性。

Numerical solutions for hypersonic aerothermodynamics of Mar's Pathfinder at Mach number 10 have been computed using the oneequation SpalartAllmaras turbulence model and the second order MUSCL upwind scheme, AUSM+ scheme combined with LUSGS implicit iteration has been used here. The numerical results derived from calorically and thermally perfect gas models have been compared with experimental data. Computed heating rates distributions with thermally perfect model are in good agreement with the experiment, however, those in separated zones are poorly predicted. It is seen that thermodynamic properties of hypersonic flows except the separated zones can be correctly simulated with this method if the mesh is appropriately designed, in particular, when the grid resolution near wall is sufficient. 