CFD analysis on the effects of distorted inlet flows with variable RPM on the stability of the transonic micro-compressor

Progressing advancement concerning the intensification of engine thrust to weight ratio in a gas turbine engine offers ascends to extremely loaded compressor stages which have a significant concern in recent times. Non-uniform Inlet flow conditions are frequently occurring in aircraft gas turbines engines that result in chronological distortions of total temperature and total pressure at the engine inlet. Distorted inlet flow operation of the axial compressor deteriorates the aerodynamic performance which reduces stall margin and increased blade stress levels. The current paper aims at the investigation of the flow field in the tip clearance region of the transonic micro-axial flow compressor at non-uniform flow conditions. Under the design and off-design RPM, the current paper focuses on the adverse effects of a steady-state distorted pattern of total pressure inlet flow conditions, including hub radial, tip radial pressure distortion, and combined effects of pressure distortion with bulk swirl flow to evaluate its effects on compressor performance and stability. The results show that like hub radial pressure distortion improves the stability range of turbofan transonic micro-compressor rotor. Whereas tip radial and counter swirl flow deteriorate the performance of the compressor. Furthermore, compressor performance alleviated the stall at higher RPM combined with distorted inlet pressure.