The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi

Chin.J.Chem.Eng. ›› 2009, Vol. 17 ›› Issue (6): 896-903.

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The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi

ZHANG Xiaodong, FU Yong, LI Zhiyi, ZHAO Zongchang

R&D Institute of Fluid and Powder Engineering, College of Chemical Engineering, Dalian University of Technology, Dalian 116012, China

Received:2009-02-17 Revised:2009-09-25 Online:2009-12-28 Published:2009-12-28
Supported by:
Supported by the National Natural Science Foundation of China (10472024)

The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi

张晓冬, 付勇, 李志义, 赵宗昌

R & D Institute of Fluid and Powder Engineering, College of Chemical Engineering, Dalian University of Technology, Dalian 116012, China

通讯作者: ZHANG Xiaodong,E-mail:zhangxd56@163.com
基金资助:
Supported by the National Natural Science Foundation of China (10472024)

Abstract

Abstract: The idea that the collapse proceeds from the outer boundary of the cavity cloud towards its center for the ultrasonic cavitation proposed by Hasson and Morch in 1980s is further developed for calculating the collapse pressure and boundaries of cavity cloud at the collapse stage of bubbles for hydraulic cavitation flow in Venturi in present research.The numerical simulation is carried out based on Gilmore's equations of bubble dynamics,which take account of the compressibility of fluid besides the viscosity and interfacial tension.The collapse of the cavity cloud is considered to proceed layer by layer from the outer cloud towards its inner part.The simulation results indicate that the predicted boundaries of the cavity cloud at the collapse stage agree well with the experimental ones.It is also found that the maximum collapse pressure of the cavity cloud is several times as high as the collapse pressure of outside boundary,and it is located at a point in the axis,where the cavity cloud disappears completely.This means that a cavity cloud has higher collapse pressure or strength than that of a single bubble due to the interactions of the bubbles.The effects of operation and structural parameters on the collapse pressure are also analyzed in detail.

Key words: cavity cloud, collapsing layer by layer, hydrodynamic cavitation, collapse pressure, bubble dynamics

摘要： The idea that the collapse proceeds from the outer boundary of the cavity cloud towards its center for the ultrasonic cavitation proposed by Hasson and Morch in 1980s is further developed for calculating the collapse pressure and boundaries of cavity cloud at the collapse stage of bubbles for hydraulic cavitation flow in Venturi in present research.The numerical simulation is carried out based on Gilmore's equations of bubble dynamics,which take account of the compressibility of fluid besides the viscosity and interfacial tension.The collapse of the cavity cloud is considered to proceed layer by layer from the outer cloud towards its inner part.The simulation results indicate that the predicted boundaries of the cavity cloud at the collapse stage agree well with the experimental ones.It is also found that the maximum collapse pressure of the cavity cloud is several times as high as the collapse pressure of outside boundary,and it is located at a point in the axis,where the cavity cloud disappears completely.This means that a cavity cloud has higher collapse pressure or strength than that of a single bubble due to the interactions of the bubbles.The effects of operation and structural parameters on the collapse pressure are also analyzed in detail.

关键词: cavity cloud, collapsing layer by layer, hydrodynamic cavitation, collapse pressure, bubble dynamics

ZHANG Xiaodong, FU Yong, LI Zhiyi, ZHAO Zongchang. The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi[J]. Chin.J.Chem.Eng., 2009, 17(6): 896-903.

张晓冬, 付勇, 李志义, 赵宗昌. The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi[J]. Chinese Journal of Chemical Engineering, 2009, 17(6): 896-903.

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The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi

The Numerical Simulation of Collapse Pressure and Boundary of the Cavity Cloud in Venturi

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