Experiment and numerical simulation on aerodynamic performance of low-loaded and highly-loaded compressor cascades

To clarify the difference in aerodynamic performance and flow transition between compressors using highly-loaded design and general design (low-loaded), the cascade experiments including suction side flow pattern and parameter measurement were performed. Based on the experimental boundary conditions, numerical researches on the suction boundary layer with γ-θ transition model were also conducted. Result showed that, compared with the low-loaded cascade, as the incidence angle increased, the flow boundary layer in highly-loaded cascade transformed from the attached flow to the separated flow, which enhanced wake width and loss and made wake integrate with corner separation loss region into a “strip-shape” loss region. Meanwhile, the flow boundary flow in low-loaded cascade was still an attached flow and the corner separation maintained open separation close to the endwall. The results indicated that highly-loaded design enhanced the inverse pressure gradient in the cascade, causing the flow more easily separated, the surface shape parameter presented a wide range of “peak” distribution, and the transition mode also changed from local bypass transition to all-span separation-induced transition.