Propulsion System Flow Stability Program (Dynamic). Part VII. Model for Predicting Compressor Performance with Combined Circumferential and Radial Distortion - Basic Theory and Model Discription.

The part contains the development and the derivation of the basic theory applicable to the analytic model for predicting compressor performance with combined circumferential and radial inlet distortion. The details of the associated computer program are presented in Part VIII, and the comparison between results obtained and experimental data is contained in Part IX. The report is divided into a number of sections. The over-all description of the computing system consists of a formulation, primarily verbal, of the approach used. Its intent is to present a physical picture of the analytical model, and to outline the computational steps which must be taken to assure its realistic solution. Two appendices include, respectively, the derivation of the basic equations, and the analytic development of the small perturbation technique used to assist the convergence process in the blade-free spaces within the over-all compressor system. A fully operable computing system capable of predicting realistically the three-dimensional flow field in the annulus of a multistage axial compressor operating with combined radial and circumferential distortion has been demonstrated on the Wright Field APL IBM 704494 directly coupled computing system. Author