Investigation of flowfield characteristics due to shock wave-boundary layer interaction on compression decompression corners using les

Karpuzcu, Irmak Taylan
Shock wave boundary layer interactions occur in industrial flows where the flow is transonic, supersonic or hypersonic and there is an incoming boundary layer present. Many of the air crafts such as planes, rockets, missiles, re-entry vehicles, and supersonic wind tunnels experience shock wave boundary layer interactions. These interactions can take place on an air craft at several different places such as the air intakes, ramps, forebody and fins, and also the diffuser section of a supersonic wind tunnel. In this thesis study, three cases of shock wave boundary layer interactions are investigated, which are compression-expansion ramp, shock impinging on a wall and shock impinging on a compression-expansion ramp. The first case is at Mach 2.88 and with a Reynolds number of 135000 based on the incoming boundary layer thickness, while others are at Mach 2.05 and a Reynolds number of 188000 based on the incoming boundary layer thickness. OpenFOAM is used as the CFD software and solutions are performed using wall modeled large eddy simulations using wall functions. For the first two cases, the results are compared with the available experimental and numerical data. The results of the third case are novel since it has not yet been studied in the literature numerically or experimentally. The results for the first two cases were comparable to experimental results in terms of pressure distribution, flow field structures and unsteadiness whereas velocity profiles and skin friction distributions showed discrepancies especially in the separation zones.


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Citation Formats
I. T. Karpuzcu, “Investigation of flowfield characteristics due to shock wave-boundary layer interaction on compression decompression corners using les,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Mechanical Engineering., Middle East Technical University, 2019.