A study of axial compressor blade optimization for operation in the low Reynolds number regime

Original and previously published experimental data is presented in this study of axial compressor blade optimization for use in the subcritical Reynolds number region. Three methods of increasing cascade performance at these low Rc are presented, discussed, and compared: (1) use of sharp-leading-edge profiles, (2) trip wires or roughness elements, and (3) high free-stream turbulence. The original data was collected in the VKI C-1 cascade wind tunnel; during these tests blade chord Reynolds number was varied from 250,000 down to about 17,000. Each technique demonstrated an increase in low Reynolds number (based on chord) performance for certain profiles, with the sharp-leading-edge profile as the potential optimum. Axial compressors or pumps that must operate for a significant amount of their design life under low Reynolds number conditions might benefit substantially from these methods.