A Nonlinear sub-grid scale model for compressible turbulent flow

作者：Li Bin^*; Wu Songping

来源：Chinese Journal of Aeronautics, 2007, 20(6): 495-500.

• large eddy simulation
• subgrid scale
• compressible flow
• nonlinear

The governing equations for large eddy simulation (LES) are obtained by filtering the Navier-Stokes (N-S) equations with standard (non-Favre filtering) spatial filter function. The filtered scale stress due to the standard filtering is then reconstructed by using the Taylor series expansion. The loss of information due to truncating the expansion up to the first derivative term is modeled by a dynamic nonlinear model (DNM), which is free from any empirical constant and wall damping function. The DNM avoids the singularity of the model and shows good local stability. Unlike the conventional dynamic Smagorinsky model (DSM), the DNM does not require the plane averaging and reduces the computational cost. The turbulent flow over a double ellipsoid for Reynolds number of 4.25 x 10(6) and Mach number of 8.02 is simulated numerically to validate the proposed approach. The results are compared with experiment data, as well as the data of Reynolds averaged numerical simulation (RANS).

• 出版日期2007-12
• 单位北京航空航天大学