Large-Eddy Simulation of Separation Control for Flow over a Wall-Mounted Hump

摘要

This work describes an implicit large-eddy simulation for active control of flow over a wall-mounted hump. Results are presented for the baseline simulation without flow control and for both steady-suction and oscillatory blowing-and-suction flow control. Results are compared with Reynolds-averaged Navier-Stokes solutions and experimental data from NASA's 2004 Computational Fluid Dynamics Validation on Synthetic Jets and Turbulent Separation Control Workshop. The baseline and steady-suction cases achieved significantly better agreement with experimental flowfield characteristics than the Reynolds-averaged Navier-Stokes simulations in the separated region downstream of the hump. Because the large-eddy simulation was accomplished at one-fifth of the experimental Reynolds number, the oscillatory flow control displayed less effectiveness than the experiment. Using a larger oscillatory amplitude exerts more control on the separation bubble. Comparing the baseline flow solution with cases using flow control clearly demonstrates the ability to reduce the size of the separated flow region in the wake of the hump.