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.