PANS方法在双圆柱绕流数值模拟中的性能分析

PANS方法以传统的雷诺平均Navier-Stokes(RANS)方程为模板,引入控制参数对原方程进行修改,是一类能够有效模拟分离湍流流动的混合方法.采用基于Menter 剪切应力输运(SST)湍流模型的PANS方法,选取双圆柱绕流作为研究对象, 分析双圆柱流动结构,验证方法的准确性与可靠性,考察PANS方法中模型参数选取对于计算结果的影响,评估不同类型PANS方法的性能.研究表明:模化湍动能比例这一模型参数对计算结果有显著影响,且计算域内统一的模型参数取值难以处理复杂流动问题.在此基础上使方法中模化湍动能比例取值随流场物理信息和网格尺度变化,所得结果与SST DES计算结果及实验结果吻合较好,表明该方法适用于复杂湍流数值模拟. 

Property assessment of PANS method for numerical simulation of flow around tandem cylinders

Partially averaged Navier-Stokes (PANS) method derived from the traditional Reynolds averaged Navier-Stokes (RANS) methods by introducing controlling parameter into original RANS equations to modify these equations, is one kind of hybrid methods which can effectively simulate the separated turbulent flows. Computational results of tandem cylinders using PANS method based on Menter shear stress transport (SST) turbulence model were presented in this investigation. The flow structures around tandem cylinders were analyzed and the accuracy and reliability of PANS method were also verified. Moreover, the influence of the model parameter on numerical results was investigated and the performance of different types of PANS methods was assessed. Studies show that the unresolved-to-total ratio of turbulence kinetic energy has significant effects on the numerical results, and taking this parameter as a constant value throughout the whole computational domain can hardly tackle the complex flow problem. Furthermore, the parameter is made to change along with flow physical information and the local grid scale. The variable f_k PANS method agrees well with the results from SST detached-eddy simulation (DES) and the experimental measurements, suggesting strong adaptability to complex turbulence simulation.