Vibration characteristics of the two‐stage throttle valve induced by cavitation

Abstract

The effect of cavitation on vibration characteristics of a two-stage throttle valve is experimentally studied by changing inlet pressure, outlet pressure and opening. The shadow photograph of the flow field in the throttle is obtained by a high-speed camera, and the signal of vibration induced by cavitation of the two-stage throttle is obtained by an acceleration sensor. It can be concluded that the fixed cavitation and the travelling cavitation in the two-stage throttle valve occur at the back of the throttle orifice. The effect of cavitation on vibration intensity and power spectral density is obvious. There are two frequency peaks in the spectrum, which are located in the vicinity of 7.5 and 12.5 kHz, respectively. These peaks correspond to travelling cavitation and fixed cavitation. The cavitation vibration intensity increases with the increase in the cavitation intensity, and the centre frequency of the signal peak near 7.5 kHZ is also moving towards the low frequency.