风 扇 转 静 干 涉 纯 音 高 精 度 数 值 模 拟

The rotor-stator interaction pure tone is a major component of fan noise. A deep understanding of its generation mechanism，and high-precision simulation and prediction are topics of mutual concern in both academia and industry. The high-order spectral difference method is used to conduct high-precision numerical simulations of fan rotor-stator interaction pure tone. Compared with experimental results，the numerical simulations accurately predict the main mode components of the rotor-stator interaction pure tone. The sound power level errors for the first three Blade Passing Frequency（BPF）dominant modes are −1. 2，+0. 8，−2. 1 dB，respectively. Among all the“CUT-ON”modes within the first three BPFs，the proportion of modes with PWL error below 5 dB is 86%，35%，and 30%，respectively. Detailed analysis of the distribution of BPF noise sources on the stator surface reveals that the BPF noise sources are primarily concentrated at the leading-edge region of the stator，originating primarily from the interactions between rotor wake and blade tip leakage vortices with stator blades，as well as unsteady separation bubbles near the pressure side of the stator leading edge.