Effects of Actuation Parameters on Flow Separation Control in Compressor with Synthetic Jets

A highly loaded compressor stator cascade with synthetic jet actuators mounted on the blade suction side is numerically investigated. The effects of actuation parameters on the performance of cascade with single-slit synthetic jet are systematically studied, and the effectiveness of segment synthetic jet on separation control is validated. Simulation results indicate that the single-slit synthetic jet has a two-way effect on the flow field: the performance improvements by the tangential momentum injection and the additional flow losses associated with the jet. Within a broad frequency range, as the jet momentum reaching its effective level, a better control effect can be obtained under the frequency of the main flow passing through the airfoil. A reductions of 14.26% for the total pressure loss coefficient can be gained under the best condition. Moreover, the segment synthetic jet can adapt to the requirements for the optimal actuated position of flow separation at different blade height, which varies along the axial direction. Compared with the single-slit synthetic jet, the flow separation can be effectively suppressed without enlarging the jet area, corresponding to a remarkable loss reductions of up to 15.84%. Additionally, the importance of forcing position is highlighted for the unsteady actuation.