The Effect of Vortex Generators on a Compressible Backward-Facing Step Flow

Wei-Chung Chang ； Ping-Han Chung ； Keh-Chin Chang

《Journal of Aeronautics, Astronautics and Aviation》 55卷2期 Vol.55 No.2 (2023/06) Pp. 135-142

https://doi.org/10.6125/JoAAA.202306_55(2).03

摘要

Flow separation reduces aerodynamic efficiency and increases energy loss. Turbulent flow past a backward-facing step is important for engineering applications in which low-frequency unsteady motions results in acoustic or structural problems. Active and passive control techniques are used to alleviate flow separation. This study uses vortex generators to control flow separation. Experiments are conducted in a transonic wind tunnel. The test matrix includes the freestream Mach number, the geometrical configuration and the height of the vortex generators. Dynamic pressure measurements (mean and fluctuating pressures) determine flow unsteadiness with and without a control device. The results allow the aerodynamic characteristics for high-speed vehicles to be determined.

關鍵字

Backward-facing step ； Vortex generator ； Flow Separation ； Compressible flow

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