Circumferential Total Pressure Distortion Of The Axial Flow Compressor Stability Simulation Studies

The flow distortions of multistage axial flow compressor inlet of fight engines is always exist. They have the severe affects on performance and aerodynamic stability of axial flow compressors. So, it is important to show those effects.An improving model of parallel compressor for predicting the effects of circumferential total pressure distortion on performance and aerodynamic stability of multistage axial flow compressors is established in this paper. This model includes changes of the rotor work point, the circumferential flow between one parallel compressor and another, and the different static pressure balance conditions of parallel compressor outlet. By using stage characteristics of multi-axial flow compressors, total performances of multi-axial flow compressors are obtained form front stage to rear stage by the way of stage-stacking. The work points of compressor are moved to the surge bound limit by increasing distorted total pressure intensity.The single stage axial flow compressor, the three-stage axial compressor of a turbine engine and eight-stage axial compressor of J85-13 are calculated as examples in this paper. By the calculation for steady characteristics of the single stage and multi-stage axial flow compressors, it is found that this model could simulate distorted condition and predict the aerodynamic stability of multi-axial flow compressors with inlet circumferential total pressure distortion condition. Distortion transfer rules of total pressure, static pressure and total temperature in multistage axial flow compressors are presented. Comparisons show the model and simulated method for the circumferential total pressure distortion are logical and they could be used for the design and analysis of engineering.