Statistical evaluation of performance impact of flow variations for a transonic compressor rotor blade

Abstract

The effects of flow variations to the aerodynamic performance of turbomachinery blades are considerable in the real world. Uncertainty quantification of aerodynamic performance is useful for evaluating the mean performance change, robust design, etc. The paper studies the performance impact of inlet and outlet flow variations for transonic compressor rotor blades using polynomial chaos. An adaptive sparse grid technique is employed to construct the model of adaptive non-intrusive polynomial chaos (ANIPC). Through statistical evaluation of performance changes for NASA Rotor 67, the response performance of ANIPC is firstly verified. Then the ANIPC is used to evaluate the changes of adiabatic efficiency and mass flow rate of Rotor 67 considering the variations of inlet total pressure and outlet back pressure at different operation conditions. The results reveal that the performance changes exhibit evident nonlinear dependence on the inlet and outlet pressure variations. Moreover, performance changes of the rotor blade in the whole operation range are evaluated and illustrated. Finally, by Monte Carlo simulation, the flow solutions along span and in the blade passage are statistically analyzed to demonstrate the impact mechanisms of inlet and outlet pressure variations to the performance changes.