Effect of rotor blade loading distribution on flow stability of transonic compressor

Abstract

The stall inception prediction method based on eigenvalue theory is established to analyze the effect of rotor blade loading distribution on the flow stability of transonic compressors. The parameterization is implemented to describe the blade geometry with a number of control parameters. Four designs with different blade loading distributions are achieved by modifying the maximum thickness position of each element profile. The steady simulations show that the variation of rotor blade loading distribution leads to significant change of the steady performance incorporating pressure ratio and efficiency at all mass flow conditions. When the blade loading is located further downstream, the pressure rise curve moves towards smaller mass flow and higher pressure ratio, while there exists an optimal blade loading distribution that maximizes the rotor peak efficiency. According to the theoretical prediction, moving the blade loading downstream leads to a smaller stall inception mass flow rate. The rotor work, entropy generation and diffusion factor of the four rotors are analyzed to explain the performance difference. And the relative positions of passage shock and unsteady tip clearance flow at design and near-stall operating conditions are compared in detail to explain the stall onset distinction.