Experimental and numerical analysis on tonal noise of single-stage axial compressor

To investigate the correlation between the tonal noise generated by rotor/stator interaction and the incoming upwash velocity of the stator， the tonal noise of a single-stage， low-speed axial compressor test rig (TA36) in a throttling process was studied by a well-developed inhouse hybrid noise prediction method. In order to accurately capture the source of the tonal noise， i.e.， unsteady pressure fluctuation on the surface of the stator blade，the effects of the simulation grid and time-step size on the prediction of the unsteady pressure fluctuation were discussed firstly. Then, the variations of upwash velocity and tonal noise in the throttling process were compared. The result showed that at the third blade passing frequency (BPF) of the design speed，the amplitude variation of the incoming upwash velocity on the 70%，80%，and 90% span of the stator was consistent with the sound pressure level predicted by the hybrid method， and kept good consistency with the experimental measurements. In addition， the sound radiation in the far field demonstrated significant directivity while the directivity did not change significantly with the mass flow rate. © 2023 BUAA Press. All rights reserved.