Enhancement of the Performance of the Partial-Averaged Navier – Stokes Method by Using Scale-Adaptive Mesh Generation

Abstract

The Partially-Averaged Navier-Stokes (PANS) approach is a recently proposed method which changes seamlessly from Reynolds-Averaged Navier-Stokes (RANS) to the direct numerical solution of the Navier-Stokes equations (DNS) as the unresolved-to-total ratios of kinetic energy and dissipation are varied. The parameter which determines the unresolved-to-total kinetic energy ratio f k is defined based on the grid spacing. The PANS asymptotic behavior goes smoothly from RANS to DNS with decreasing f k . In the work of Basara, Krajnovic and Girimaji (Proceedings of ERCOFTAC 7th International Symposium on Engineering Turbulence Modelling and Measurements ETMM7, 2/3, pp. 548–554, Lymassol, Cyprus, 2008), it was shown that a dynamic update of the PANS key parameter f k by changing at each point and at the end of every time step, is the promising approach to provide the optimum modeling on employed computational meshes. This work is extended here by introducing the adaptive local grid refinement which keeps in advance prescribed value of the parameter f k . The results show benefits of using such advanced numerical technique in conjunction with the PANS method.