Design and Testing of a Controlled Diffusion Airfoil Cascade for Industrial Axial Flow Compressor Application

Abstract

Similar to jet engine development, modern design methods are used today to improve the performance of industrial compressors. In order to verify the loading limits, a cascade profile representative for the first rotor hub section of an industrial compressor has been designed by optimizing the suction surface velocity distribution using a direct boundary layer calculation method. The blade shape was computed with an inverse full potential code and the resulting cascade was tested in a cascade wind tunnel. The experimental results confirmed the design intent and resulted in a low loss coefficient of 1.8 percent at design condition and an incidence range of nearly 12 deg (4 percent loss level) at an inlet Mach number of 0.62.