Design and Performance Evaluation of Four Transonic Compressor Rotors

A set of four compressor rotors was designed as a means of optimizing blade camberline shape in the high-transonic Mach number region. One blade row was designed for a tip diffusion factor of 0.35 with the supersonic camber minimized. The other three blade rows were designed for a tip diffusion factor of 0.45 with tip ratios of supersonic to total camber varying from zero to the value corresponding to a double-circular-arc blade section. Performance maps and blade element data were generated as a result of testing on the four rotors. All rotors exceeded design efficiency and flow at conditions corresponding to design point operation. Operating range, from peak efficiency to stall, is highest in rotors designed for a low tip diffusion factor and which have the minimum amount of supersonic camber.