産業用遠心ポンプのファン型インデューサにおけるキャビテーション不安定現象の挙動と騒音の関係

抄録

Cavitation in industrial pumps is caused increasing noise and vibration, in addition to decreasing pump instability. Therefore, it is important to predict the occurrence of cavitation at the design and test stage. Noise is often used to observe condition of cavitation and pump. In this study, an air-borne microphone was set near the inducer and noise was measured as part of the establishment for a cavitation evaluation method using noise data. The visualization test using an acrylic casing and a high-speed camera was conducted to observe the cavitation behavior. From these results, the relationship between noise and various cavitation phenomena was investigated. Experimental results showed noise was decreased when sheet cavitation had occurred at the entire flow path around the inducer, and the noise level was decreased in wide bandwidth above 1 kHz. However, there was no significant difference in the specific frequencies, regardless of the cavitation instability phenomenon.