Efficient methods for prediction and evaluation of compressor rotor blades forced response considering multiple excitation from asymmetric stators

Asymmetric stators, featuring nonuniform pitches, have demonstrated effectiveness in mitigating the forced response of the adjacent compressor rotor blades. However, the lack of comprehensive understanding of their vibration reduction mechanisms hinders the development of optimal designs. Typically, the evaluation of rotor blades forced response using asymmetric stators requires fluid–structure interaction methods and full-annulus computational domains; however, these methods are time-consuming and resource-intensive, making them unsuitable for rapid engineering applications. To address these issues, the present study first develops a Fourier-based prediction method for the excitation spectrum and blade forced response that considers the impacts of multiple excitation components. To verify the accuracy of the prediction method, two typical asymmetric stator configurations are selected, and the forced response analyses with single-passage computational domains are conducted on their downstream rotor blades based on the rapid time inclination method. The results are then compared with those obtained using the dual time stepping method with whole-annulus computational domains. The results indicate that the proposed Fourier-based method can accurately predict the impacts of asymmetric stators on the forced response of the rotor blades. Moreover, the rapid evaluation approach based on the time inclination method provides comparable accuracy to the dual time stepping method, but with greater computational efficiency and reduced memory consumption.