Discontinuous Galerkin Turbulent Flow Simulations of NASA Turbulence Model Validation Cases and High Lift Prediction Workshop Test Case DLR-F11

Abstract

A high-order Discontinuous Galerkin (DG) solver is used to simulate three turbulent flow simulations. Two of these simulations come from the NASA turbulence modeling resource and include turbulent flow over a hemisphere-cylinder and turbulent flow over a 3D bump in a channel. The third simulation is the DLR-F11 from the second high-lift prediction workshop. The flow is simulated by solving the Reynolds-Averaged Navier-Stokes equations closed by the negative Spalart-Allmaras turbulence model. For these simulations, lift, drag, pitching moment, pressure, and skin friction coefficients are provided for multiple grids and discretization orders and compared against other simulation results from well known finite-volume solvers. The simulations give very similar results to these benchmark solvers, pointing towards fully mesh resolved simulations and providing verification evidence of correct and consistent implementation of these discretizations. Results obtained using the high-order DG discretizations show higher accuracy using fewer degrees of freedom compared to the finite-volume discretizations. Also, it is shown for the DG simulations that p-refinement converges quicker to the mesh resolved solutions compared to h-refinement. However, there are still issues with the efficiency of DG and the time to solution is still an order of magnitude slower compared to finite-volumes methods such as NSU3D.