Numerical Simulation of Rotor Clocking Effect in a Low-Speed Compressor

Two-dimensional (2D) unsteady numerical simulation has been applied to study the effect of the variation in relative circumferential positions of rotors on the performance of a low speed compressor. The result shows that the variation will change the relative position of upstream rotor wake to the downstream rotor as well as the periodic and turbulent velocity fluctuations on the airfoils. When the upstream rotor wake impinges upon the leading edge of the downstream rotor, the corresponding stage efficiency will be higher; when the upstream wake is transferred into the mid-passage of the downstream rotor, the corresponding stage efficiency will be lower. The proper configuration of the relative position of rotors will cause obvious reduction in the unsteady aerodynamic effect on the second rotor airfoils and improve the aerodynamic performance of blades.