Off-Design Behavior for Axial Flow Compressor Stages with Invariable and Variable Geometry Blades,

Abstract : An application of a computer program is described for studying the off-design performance for single and multistage axial flow compressors. The calculation method allows one to determine the stage characteristics as a function of revolutions. This can be accomplished in a very short time with only a few geometrical and aerodynamical input data. The flow is described by the well-known streamline curvature method. The necessity of a good loss model is shown. Limitations of this method are described. Some computation examples for the first and fifth stages of a ten-stage NASA axial flow compressor are presented. The stage and overall characteristics for different compressors are considered for invariable and variable blade geometry. The off-design analytical results are compared with existing experimental results. (Author)