Boundary Layer Optimization for the Design of High Turning Axial Flow Compressor Blades

Abstract

An optimization method, based on Le Foll’s boundary layer theory and on Goldstein’s conformal mapping method is described. The parameters of optimization are circulation per blade and absolute losses. The problem is treated as an inverse problem (i.e., the best blading is found starting from the flow conditions imposed). The performance of a highly loaded compressor cascade, designed according to the method presented and tested in a low speed wind tunnel, is compared with the theoretical predictions. Some discrepancies exist which are due to the influence of flow convergence and blade curvature. A modification of the method to take into account these effects is discussed.