Suppression of cavitation inception by gas bubble injection: A numerical study focusing on bubble-bubble interaction

A two-dimensional pulsating flow of a viscous fluid in a plane channel whose wall has rectangular microcavities partially or completely filled with a compressible gas is investigated. This problem formulation can clarify the friction reduction mechanism in a laminar sublayer of a turbulent viscous boundary layer flow over a textured stripped superhydrophobic surface containing periodically arranged rectangular micro-cavities filled with gas. It is assumed that the dimensions of the cavities are much smaller than the channel thickness. On the macroscale, the problem of one-dimensional unsteady viscous flow in a plane channel with no-slip conditions on the walls and a harmonic variation of the pressure difference is solved. The solution obtained in this way is used for formulating non-stationary in time and periodic in space boundary conditions for the flow on the scale of a chosen cavity (microscale), with the instantaneous volume of the gas bubble in the cavity depending on the instantaneous pressure over the cavity. The flow on the microscale near a cavity with a gas bubble occurs in the Stokes regime. The numerical solution is obtained using an original version of the boundary element method. A parametric numerical study of the flow field in a pulsating shear flow over a cavity with a compressible gas bubble is performed. The averaged parameters characterizing the effective ‘velocity slip’ of viscous fluid and the friction reduction in a pulsating flow over a stripped superhydrophobic surface are calculated.

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The effect of thixotropy on a rising gas bubble: A numerical study

Korea-Australia Rheology Journal ◽

10.1007/s13367-016-0021-8 ◽

2016 ◽

Vol 28 (3) ◽

pp. 207-216 ◽

Cited By ~ 3

Author(s):

Kayvan Sadeghy ◽

Mohammad Vahabi

Keyword(s):

Numerical Study ◽

Gas Bubble

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A numerical study of parameters affecting gas bubble dissolution

Journal of Colloid and Interface Science ◽

10.1016/0021-9797(89)90049-0 ◽

1989 ◽

Vol 127 (2) ◽

pp. 442-452 ◽

Cited By ~ 5

Author(s):

Chain-Nan Yung ◽

Kenneth J De Witt ◽

Jonathan L Brockwell ◽

John B McQuillen ◽

An-Ti Chai

Keyword(s):

Numerical Study ◽

Gas Bubble

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The Influence of Velocity and Scale on Cavitation Inception where Wall-Generated Gas Bubbles are the Sole Source of Cavitation Nuclei

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1975_017_009_02 ◽

1975 ◽

Vol 17 (2) ◽

pp. 45-51

Author(s):

M. R. Baum

Keyword(s):

Bubble Growth ◽

Flow System ◽

Scale Effects ◽

Gas Bubbles ◽

Sole Source ◽

Gas Bubble ◽

Cavitation Inception ◽

Boundary Wall ◽

Cavitation Nuclei ◽

System Properties

It is established, using recently derived expressions relating the flow system properties to the size at which a gas bubble grown at a boundary wall will become detached, that the commonly observed variation in cavitation inception pressure with velocity in a given system can be simply attributed to variations in the size of bubble detached. However, it is concluded, from a comparison of predicted and experimental variations of inception pressure with scale of the system, that when considering scale effects the pressure necessary to promote gas-bubble growth must also be taken into account.

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Effects of Liquid Properties on Acoustic Gas Bubble Radial Oscillation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.351 ◽

2013 ◽

Vol 774-776 ◽

pp. 351-357

Author(s):

Jun Cai ◽

Xiao Qian Chen ◽

Yong Chen ◽

Yi Yong Huang

Keyword(s):

Numerical Study ◽

Radial Oscillation ◽

Fluid Viscosity ◽

Gas Bubble ◽

Bubble Oscillation ◽

Stable Oscillation ◽

Proposed Model

To analyze the radial oscillation of forced acoustic gas bubble in liquid, a revised model including the effect of compressibility is mathematically formulated. Based on proposed model, the effects of fluid viscosity and temperature are discussed respectively. Numerical study demonstrates that gas bubble oscillation may change from nonlinear chaos into linear one due to the augmentation of fluid viscosity. Meanwhile, the stable oscillation may diverge with a sensible rise in temperature.

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