Numerical investigation of sweeping jet actuator frequency and jet flow effects on corner separation control

Due to the high efficiency and flow capacity efficiency, axial compressors show great potential for application in Compressed Air Energy Storage systems. To improve the stability and overall performance of Compressed Air Energy Storage systems, in this study, the unsteady Reynolds-averaged Navier-Stokes method is employed to investigate the effects of SJA on the internal flow structure of an axial compressor cascade. The sweeping frequency and jet flow rate of the Sweeping Jet Actuator are independently analyzed to assess their respective influences on the aerodynamic performance of the cascade. The results indicate that sweeping frequency plays a crucial role in suppressing corner separation and reducing total pressure loss. At the optimal frequency of 1000 Hz, the SJA reduces the total pressure loss coefficient by approximately 15 %. The underlying mechanism is that variations in sweeping frequency alter the momentum input characteristics of the jet into the mainstream, thereby shifting its effective control region within the cascade and modifying its suppression effects on the passage vortex and concentrated shedding vortex. Moreover, reducing the jet flow rate can significantly improve the energy efficiency of the compressor cascade, while having only a minimal impact on the total pressure loss.