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双方程k-ω剪切应力输运(SST)湍流模型通常以隐式耦合方式或者显式半耦合/解耦的方式来求解。本文提出了该模型的一种显式耦合应用方法,即通过点隐的方式来处理湍流源项的刚性,并与混合Runge-Kutta时间推进以及当地时间步长、隐式残差光顺等加速收敛技术相结合,从而使得湍流方程可以与流动方程同时求解。为了增强计算的鲁棒性,进一步对湍流变量进行了限制。将所发展的方法用于DLR平面叶栅算例,确认了求解结果的正确性以及刚性的来源。通过对三维NASA Rotor 67的模拟,验证了SST模型的精度;进一步将其与Badwin-Lomax(BL)模型、Spalart-Allmaras(SA)模型对比,发现三者都能正确地捕捉出口参数分布,且SST与SA模型的模拟结果比较一致;对于该算例,SST模型在总温模拟上更具优势,而BL模型在总压分布上与试验值更加接近。
The two-equation k-ω shear stress transport (SST) turbulence model is usually solved by implicit coupling or explicit coupling / decoupling. In this paper, an explicit method for coupling the model is proposed, which deals with the rigidity of the turbulent source term by implicit method and is accelerated with the hybrid Runge-Kutta time advancement and the local time step, implicit residual smoothing Convergence technique, so that the turbulent flow equation can be solved simultaneously with the flow equation. In order to enhance the robustness of the computation, turbulence variables are further limited. The developed method was applied to the DLR plane cascade example, confirming the correctness of the solution and the source of rigidity. The accuracy of the SST model was verified by simulating the three-dimensional NASA Rotor 67. Comparing it with the model of Badwin-Lomax (BL) and the Spalart-Allmaras (SA) model, it was found that all the three models correctly captured the exit parameter distribution The results of SST and SA model are consistent. For this example, the SST model is more advantageous in the overall temperature simulation, while the BL model is closer to the total pressure distribution.