A nonlinear Partially-Averaged Navier-Stokes model for turbulence

Most of the RANS turbulence models solved the Reynolds stress by linear hypothesis and they were isotropic models. At present, Partially-Averaged Navier-Stokes (PANS) has been found to be better than that of the LES with less mesh in the near-wall region. In this paper, a new nonlinear PANS turbulence model was proposed, which was modified from RNG k-ε turbulence model and the Reynolds stresses were solved by nonlinear methods. The new nonlinear PANS turbulence model was used to simulate the flow fields around a NACA0015 hydrofoil, in a curved rectangular duct and a low specific centrifugal pump. The results based on the new nonlinear PANS model agreed well with the experimental results. The calculation results proved that the nonlinear PANS model is available for high pressure gradient flows, large curvature flows, and it can be used to capture complex vortexes in a turbomachinary.