오리피스내에서 발생한 공동소음 스케일링 연구

초록

The major source of noise in the process of transporting liquids is related to the cavitation phenomenon. In this investigation, an orifice configuration is set-up to correlate its flow-field and acoustic signatures with those from a control valve device. The sound powers from the orifice configuration are effectively normalized using scaling parameters. Flow-excited dynamic systems for which there is no strong coupling between the flow and the system response can be described using a linear source-filter model. On this assumption, the normalized sound power can be decomposed of noise source function and a response function. To find noise sources, pressure spectra measured over a range of pressure differences are transformed into the products of two non-dimentional frequency function : Pss(He,fca,x/D) = F(fca) G(He,x/D). This scheme of finding noise sources is shown to be applicable to the cavitation noise effectively.