Development of a cascade simulation of fan-passage flow

Abstract

A small-scale blowdown wind tunnel apparatus was developed to investigate techniques to alleviate the negative effects of shock-boundary layer interaction in the blading of aircraft engine fans. Using shadowgraph and surface injection techniques, probe surveys and static pressure measurements, it was shown that acceptable periodicity and repeatability could be obtained in a two-passage cascade model at M=1.4 if air supply pressure, back pressure and porous-wall bleed pressures were properly controlled. It was also shown that local separation due to shock boundary layer interaction was present at the design flow incidence of 1. 15 degrees, but not at 0.85 degrees. Complete data are reported for the design condition to serve as a baseline for separation alleviation experiments. Necessary hardware and software developments are also documented.