Control of compressor tip leakage flow using plasma actuation

Control of the compressor tip leakage flow using plasma actuation is studied in this paper based on a compressor cascade model. Three types of plasma actuation layouts are designed: the axial plasma actuation which induces body force along the axial flow direction, the normal plasma actuation which induces body force normal to the interface between the tip approaching and leakage flow, and the stagger angle plasma actuation which induces body force normal to the blade chordwise direction. Influences of plasma actuation on the compressor cascade tip total pressure loss and blockage as well as the flow structures are first studied numerically and the corresponding flow control law is obtained. The numerical results are then verified through experiments. At last, the flow control mechanism behind the suppression of compressor tip leakage flow using plasma actuation is investigated. It is found that the key element of plasma actuation in suppressing the compressor tip leakage flow lays in improving the axial momentum of compressor cascade tip flow. The optimal flow control effect in suppressing tip leakage flow is achieved with the axial plasma actuation that is the most effective in improving the axial momentum of compressor tip flow.