Numerical Simulation of Unsteady Internal Flows using Dual Time Stepping Method

The Dual Time Stepping method has been applied to the numerical simulation of unsteady internal flows using a Reynolds-Averaged Navier-Stokes (RANS) solver with transport equation turbulence models. The first two test cases are purely numerical. Simulations have provided comparisons of computational performances between the DTS method and a time-explicit method. Furthermore, the turbulent computations have demonstrated the influence of the solution strategy for the RANS/turbulent decoupled systems in order to improve the efficiency. For the last test case — cavity flow —, the existence of a database has allowed to verify the relevancy of the DTS results. The numerical prediction is satisfactory since it provides a good description of such a flow.