高超声速热流计算湍流模型性能评估

采用计算流体力学方法,通过对高超声速来流下双椭球热流计算,综合分析了影响壁面热流预测精度的因素.针对工程上4种常用的湍流模型:BL(Baldwin-Lomax)模型、SA(Spalart-Allmaras)模型、k-ω模型及SST(Shear-Stress Transport)模型,评估了其在高超声速热流预测中的性能,获得了湍流模型下壁面法向网格雷诺数对热流计算的影响规律.此外,对高马赫数下不同后掠角钝舵模型进行热流计算,获得了后掠角对钝舵前缘热流峰值的影响规律.研究表明,两方程湍流模型相比一方程和零方程模型更适合高超声速气动热计算,其中SST模型对热流预测精度更高,总体性能更为优异;钝舵驻点线最大热流随后掠角增大呈非单调变化,在后掠角约为22°时热流达到峰值. 

Property evaluation on turbulence models calculation in hypersonic heat transfer simulation

Factors that influence the prediction accuracy of hypersonic heat transfer simulation under turbulence were studied with the double ellipsoid model by the means of computational fluid dynamic. Four popular turbulent models, which include the Baldwin-Lomax(BL) model, the Spalart-Allmaras(SA) model, the Wilcox k-ω model and the Menter shear-stress transport(SST) model, were employed in the study of heat transfer simulation, their performances were assessed, the dependence of heat transfer on grid Reynolds number was assessed. Besides, the connection between sweep angle and the heat in stagnation point was established by simulation with seven different sweep angles in blunt fin. The results indicate that the Two equation model, especially the SST model, is more suitable for the heat transfer simulation in reattaching flow than the One equation model and the Zero equation model. The results also show that the maximum heat of blunt fin varies non-monotonic with the sweep angle and reaches a peak value when the sweep angle is about 22°.