Compressor cascade cross flow control via endwall passage vortex generator

Endwall cross flow is a critical factor in inducing corner separation in compressors, substantially influencing their aerodynamic performance. To address this issue at its source, this study investigates the application of vortex generators (VGs) to the endwall of the compressor cascade passage, positioned between the leading and trailing edges. Two configurations—single VG and double VG—are designed and analyzed. Using a combination of experimental and numerical methods, the study evaluates the effectiveness of the endwall passage VG technique in mitigating endwall cross flow and controlling corner separation. In addition, it uncovers the underlying flow control mechanisms and provides design guidelines. Experimental results show that both the single VG and double VG schemes effectively suppress endwall cross flow near the suction side of the compressor cascade, thereby controlling corner separation and markedly enhancing aerodynamic performance. Under an inlet Mach number of 0.6 and an incidence angle of −7°, the single VG scheme reduces the total pressure loss coefficient of the compressor cascade by 9.0%. The success of the endwall passage VG technique lies in its dual action: the direct blocking effect of the VG on the endwall cross flow, and the suppression of endwall cross flow by the concentrated vortex it generates. Together, these mechanisms constitute the key to effectively controlling corner separation in compressor cascades. Moreover, this concentrated vortex further weakens the passage vortex, thereby improving the endwall flow field.