Investigation of a cavitation bubble between a rigid boundary and a free surface

2007 ◽  
Vol 102 (9) ◽  
pp. 094904 ◽  
Author(s):  
Peter Gregorčič ◽  
Rok Petkovšek ◽  
Janez Možina
Keyword(s):  
Free Surface ◽  
Cavitation Bubble ◽  
Rigid Boundary

scholarly journals A note on the instantaneous streamlines, pathlines and pressure contours for a cavitation bubble near a boundary

1984 ◽  
Vol 26 (1) ◽  
pp. 31-44 ◽  
Author(s):  
P. Cerone ◽  
J. R. Blake
Keyword(s):  
Free Surface ◽  
Stagnation Point ◽  
Cavitation Bubble ◽  
Maximum Pressure ◽  
Rigid Boundary ◽  
Initial Distance ◽  
Bubble Pressure ◽  
Collapse Phase

AbstractInstantaneous streamlines, particle pathlines and pressure contours for a cavitation bubble in the vicinity of a free surface and near a rigid boundary are obtained. During the collapse phase of a bubble near a free surface, the streamlines show the existence of a stagnation point between the bubble and the free surface which occurs at a different location from the point of maximum pressure. This phenomenon exists when the initial distance of the bubble is sufficiently close to the free surface for the bubble and free surface to move in opposite directions during collapse of the bubble. Pressure calculations during the collapse of a cavitation bubble near a rigid boundary show that the maximum pressure is substantially larger than the equivalent Rayleigh bubble of the same volume.

scholarly journals A note on the impulse due to a vapour bubble near a boundary

1982 ◽  
Vol 23 (4) ◽  
pp. 383-393 ◽  
Author(s):  
J. R. Blake ◽  
P. Cerone
Keyword(s):  
Free Surface ◽  
Point Source ◽  
Cavitation Bubble ◽  
High Speed ◽  
Liquid Jet ◽  
Vapour Bubble ◽  
Rigid Boundary ◽  
Two Fluids ◽  
Collapse Phase

AbstractAn expression for the impluse due to a vapour (cavitation) bubble is obtained in terms of an integral over a nearby boundary. Examples for a point source near a free surface, rigid boundary, inertial boundary and a fluid of different density are considered. It appears that the sign of the impluse determines the direction a cavitation bubble will migrate and the direction of the high speed liquid jet during the collapse phase. The theory may explain recent observations on buoyant bubbles near an interface between two fluids of different densities.

scholarly journals Numerical Simulation for Cavitation Bubble Near Free Surface and Rigid Boundary

2015 ◽  
Vol 56 (4) ◽  
pp. 534-538 ◽  
Author(s):  
Kanae Oguchi ◽  
Manabu Enoki ◽  
Naoya Hirata
Keyword(s):  
Numerical Simulation ◽  
Free Surface ◽  
Cavitation Bubble ◽  
Rigid Boundary

Investigation of cavitation bubble collapse near rigid boundary by lattice Boltzmann method

2016 ◽  
Vol 28 (3) ◽  
pp. 442-450 ◽  
Author(s):  
Ming-lei Shan ◽  
Chang-ping Zhu ◽  
Xi Zhou ◽  
Cheng Yin ◽  
Qing-bang Han
Keyword(s):  
Lattice Boltzmann Method ◽  
Lattice Boltzmann ◽  
Cavitation Bubble ◽  
Bubble Collapse ◽  
Rigid Boundary ◽  
Boltzmann Method

scholarly journals Cavitation and bubble dynamics: the Kelvin impulse and its applications

2015 ◽  
Vol 5 (5) ◽  
pp. 20150017 ◽  
Author(s):  
John R. Blake ◽  
David M. Leppinen ◽  
Qianxi Wang
Keyword(s):  
Cavitation Bubble ◽  
High Speed ◽  
Bubble Dynamics ◽  
Clinical Medicine ◽  
Bubble Collapse ◽  
Rigid Boundary ◽  
Design Problems ◽  
Practical Applications ◽  
Wide Range ◽  
Naval Engineering

Cavitation and bubble dynamics have a wide range of practical applications in a range of disciplines, including hydraulic, mechanical and naval engineering, oil exploration, clinical medicine and sonochemistry. However, this paper focuses on how a fundamental concept, the Kelvin impulse, can provide practical insights into engineering and industrial design problems. The pathway is provided through physical insight, idealized experiments and enhancing the accuracy and interpretation of the computation. In 1966, Benjamin and Ellis made a number of important statements relating to the use of the Kelvin impulse in cavitation and bubble dynamics, one of these being ‘One should always reason in terms of the Kelvin impulse, not in terms of the fluid momentum…’. We revisit part of this paper, developing the Kelvin impulse from first principles, using it, not only as a check on advanced computations (for which it was first used!), but also to provide greater physical insights into cavitation bubble dynamics near boundaries (rigid, potential free surface, two-fluid interface, flexible surface and axisymmetric stagnation point flow) and to provide predictions on different types of bubble collapse behaviour, later compared against experiments. The paper concludes with two recent studies involving (i) the direction of the jet formation in a cavitation bubble close to a rigid boundary in the presence of high-intensity ultrasound propagated parallel to the surface and (ii) the study of a ‘paradigm bubble model’ for the collapse of a translating spherical bubble, sometimes leading to a constant velocity high-speed jet, known as the Longuet-Higgins jet.

scholarly journals Direction of the microjet produced by the collapse of a cavitation bubble located in a corner of a wall and a free surface

2021 ◽  
Vol 6 (8) ◽  
Author(s):  
Akihito Kiyama ◽  
Takaaki Shimazaki ◽  
José Manuel Gordillo ◽  
Yoshiyuki Tagawa
Keyword(s):  
Free Surface ◽  
Cavitation Bubble

Dynamic Characteristics of a Submerged, Flexible Cylinder Vibrating in Finite Water Depths

1992 ◽  
Vol 36 (02) ◽  
pp. 154-167
Author(s):  
A. Ergin ◽  
W. G. Price ◽  
R. Randall ◽  
P. Temarel
Keyword(s):  
Free Surface ◽  
Resonance Frequency ◽  
Water Depth ◽  
Dynamic Characteristics ◽  
Mode Shapes ◽  
Flexible Cylinder ◽  
Rigid Boundary ◽  
Fluid Structure ◽  
Resonance Frequencies ◽  
Theoretical Predictions

This paper presents experimental data and theoretical predictions of the dynamic characteristics (natural and resonance frequencies, mode shapes) of a flexible cylinder vibrating in air and at fixed positions below a free surface in water of finite depth. The flat-ended, thin cylindrical shell of overall length 1284 mm, external radius 180 mm, thickness 3 mm is made of mild steel. In the experiments, the shell was tethered (i) at 0.21, 0.23, and 0.68 m depths below the free surface in water of depth 1.6 m and (ii) at 0.25, 1.5, and 3.5 m depths in 4 m of water. The resonance frequency data recorded provide measures of the influences of free surface, cylinder position, rigid boundary, water depth, etc. occurring in the fluid-structure interaction process. The theoretical predictions are derived from a three-dimensional hydroelastic mathematical model which, through the calculations of the generalized fluid loadings, accounts for the influence of free surface and rigid boundaries, position of submerged cylinder, neutral buoyancy or, as in the present case, with tethers and buoyancy effects. An extensive comparison of results is included. The experimental restrictions of water depth, cylinder position, etc. and the fluid-structure interactions are assessed and illustrated through the calculated resonance frequency values.

Role of rigid boundary on the decay of turbulence generated by passive-grid for free surface flow

2020 ◽  
pp. 095440622094256 ◽  
Author(s):  
Pankaj Kumar Raushan ◽  
Santosh Kumar Singh ◽  
Koustuv Debnath
Keyword(s):  
Free Surface ◽  
Near Field ◽  
Flow Characteristics ◽  
Joint Probability ◽  
Mesh Size ◽  
Free Surface Flow ◽  
Surface Flow ◽  
Solid Boundary ◽  
Joint Probability Distribution ◽  
Rigid Boundary

The present study aims to investigate the flow characteristics of grid-generated turbulence under the consideration of solid boundary in free surface flow. To understand the nature of isotropy and anisotropy in the flow, the turbulent intensity is evaluated at the downstream of the grid for different mesh sizes. The energy spectrums based on the Fast Fourier and marginal Hilbert–Huang transform are presented to understand the decay of energy in the associated spectral frequency domain. It is observed that the peak of energy associated with the Fourier spectrum decreases in the near-field region of the grid with the increase in mesh size of the grid. Further, to characterise the concentrated velocity fluctuations, the paper strives to analyse the joint probability distribution function and the local intermittency measure in the close and far stream of the grid. The autocorrelation functions and the magnitude of integral length scale of the stream-wise fluctuating velocity components are also presented at two different vertical levels from the solid boundary. The normalised Shannon entropy is also evaluated to characterise the degree of the orderness or disorderness in the flow due to the interaction of grid and rigid boundary.

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