Characterisation of a multi-frequency cavitation vessel

• Published in: IOP conference series. Materials Science and Engineering Vol. 42; no. 1; pp. 12013 - 4
• Main Authors: Wang, L, Memoli, G, Butterworth, I, Hodnett, M, Zeqiri, B
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 01.01.2012
• Subjects: Acoustic emission; Acoustics; Broadband; Cavitation; Derivatives; Electric potential; Erosion; Hydrophones; Locking; Locks; Pollution monitoring; Pressure distribution; Self tuning; Sonoluminescence; Stress concentration; Vessels
• ISSN: 1757-8981; 1757-899X
• DOI: 10.1088/1757-899X/42/1/012013

A multi-frequency reference vessel (RV-multi) has been established at NPL, with the ultimate aim of establishing a standard source of acoustic cavitation in water. The vessel is a cylindrical cavity and can work at 6 frequencies, from 21 kHz up to 140 kHz, in controlled temperature conditions. RV-multi is capable of self-tuning its driving frequency to lock onto a fixed modal pattern, based on the maximised phase derivative of the driving voltage signal. The ability of system self-locking was tested under various power levels. As part of the validation process for the new reference vessel, its performance has been investigated using various methods. A small hydrophone was used to determine the acoustic pressure distribution along selected planes of symmetry inside the vessel. The generated cavitation distribution was also monitored using sonoluminescence, erosion and acoustic emission. In a novel step, broadband laser vibrometry was used to measure the motion of the vessel wall to investigate the feasibility of a non-invasive method of cavitation detection.