A nonlinear partially-averaged Navier-Stokes model for turbulence flow simulations
Liu Jintao1, Zuo Zhigang2, Liu Shuhong2, Wu Yulin2, Wang Leqin3
1. Beijing Institute of Control Engineering, Beijing 100090, China; 2. Department of Thermal Engineering, State Key Laboratory of Hydro-science and Engineering, Tsinghua University, Beijing 100084, China; 3. Institute of Process Equipment, Zhejiang University, Hangzhou, Zhejiang 310027, China
Abstract：Most of the RANS turbulence models solve the Reynolds stresses by using linear and isotro-pic hypothesis, causing inaccurate predictions for turbulent flows with severe adverse pressure gradient, or recirculation flows with large curvature or complicated separated flows. At present, partially-averaged Navier-Stokes(PANS)method has been found to be better than the LES with less mesh cells in the near-wall region. In this paper, a new nonlinear PANS turbulence model is proposed by modifying the RNG k-ε turbulence model and introducing a nonlinear method for solving the Reynolds stresses. The new PANS model is used to simulate the turbulent flow fields around a NACA0015 hydrofoil and in a 90° curved rectangular cross-section duct. The predicted results agree well with the experimental data, showing a more accuracy under strong adverse pressure gradient. This suggests the model can predict 3D nonlinear turbulent flows induced by separation precisely. The effectiveness, which the nonlinear PANS model captures the behavior of turbulent flows with strong adverse pressure gradient and large curvature, has been proven. The model potentially can be used to predict complex vortex patterns in a turbomachine.
刘锦涛, 左志钢, 刘树红, 吴玉林, 王乐勤. 一种湍流计算的非线性PANS模型[J]. 排灌机械工程学报, 2015, 33(7): 572-576.
Liu Jintao, Zuo Zhigang, Liu Shuhong, Wu Yulin, Wang Leqin. A nonlinear partially-averaged Navier-Stokes model for turbulence flow simulations. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(7): 572-576.
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