A Theoretical Investigation of the Jet-Flap Compressor Cascade in Incompressible Flow

Abstract

The use of jet flaps gives a new possibility of achieving high turning cascades. In this paper a new theory for unstaggered cascades with jet flaps, developed under simplifying assumptions, is described. With the help of this theory, besides turning angles and lift coefficients, for the first time pressure distributions on, and jet slope distributions behind, the blades were calculated. The effect of stagger angle on the turning angles and lift coefficients is determined with the help of the Schlichting method, using the concept of the equivalent flat plate cascade. Sample calculations illustrate the theory and, at the same time, give an insight into the behavior of cascades with jet flaps in inviscid flow. Results of previously published experiments on cascades with jet flaps, where they fulfill the conditions of the theory, are compared with the theoretical results and demonstrate satisfactory agreement.