遠心圧縮機の騒音に関する研究 : 第1報, ディフューザの羽根の影響

抄録

Noise in compressor stages with two vaned diffusers and a stage with one vaneless diffuser are measured. The overall noise level and the blade-passing frequency (BPF) component level in the vaned diffuser stages are higher than those of the vaneless diffuser stage. The difference in the BPF components of the two types of diffuser varies with the rotatinal speed of the impeller. Under certain conditions, the large noise which the BPF component is extremely high and sounds like a whistle is observed. Measurements of pressure fluctuation in the vaned diffuser passage show a standing wave in the flow passage, and so the loud noise is considered to be caused by resonance in the vaned diffuser. The resonance frequency is affected by the diffuser vane shape.