Water Science and Engineering 2010, 3(3) 321-330 DOI:   10.3882/j.issn.1674-2370.2010.03.008  ISSN: 1674-2370 CN: 32-1785/TV

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Keywords
orifice plate cavitation
gas nucleus
critical radius
critical pressure
pressure fluctuation
critical cavitation number
Authors
YI Mo-Zheng
PubMed
Article by Yi,M.Z

Orifice plate cavitation mechanism and its influencing factors

Wan-zheng AI, Tian-ming DING

Marine College of Zhejiang Ocean University, Zhoushan 316000, P. R. China

Abstract

The orifice plate energy dissipater is an economic and highly efficient dissipater. However, there is a risk of cavitaion around the orifice plate flow. In order to provide references for engineering practice, we examined the cavitation mechanism around the orifice plate and its influencing factors by utilizing mathematical analysis methods to analyze the flow conditions around the orifice plate in view of gas bubble dynamics. Through the research presented in this paper, the following can be observed: The critical radius and the critical pressure of the gas nucleus in orifice plate flow increase with its initial state parameter ; the development speed of bubbles stabilizes at a certain value after experiencing a peak value and a small valley value; and the orifice plate cavitation is closely related to the distribution of the gas nucleus in flow. For computing the orifice plate cavitation number, we ought to take into account the effects of pressure fluctuation. The development time of the gas nucleus from the initial radius to the critical radius is about 10-7-10-5 s; therefore, the gas nucleus has sufficient time to develop into bubbles in the negative half-cycle of flow fluctuation. The orifice critical cavitation number is closely related to the orifice plate size, and especially closely related with the ratio of the orifice plate radius to the tunnel radius. The approximate formula for the critical cavitation number of the square orifice plate that only considers the main influencing factor was obtained by model experiments.

Keywords orifice plate cavitation   gas nucleus   critical radius   critical pressure   pressure fluctuation   critical cavitation number  
Received 2008-12-15 Revised 2010-07-09 Online: 2010-09-27 
DOI: 10.3882/j.issn.1674-2370.2010.03.008
Fund:

National Nature Science Foundation

Corresponding Authors: Wan-zheng AI
Email: aiwanzheng@hhu.edu.cn
About author:

References:

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