Bubble dynamics and pressure field characteristics of underwater detonation gas jet generated by a detonation tube

2021 ◽  
Vol 33 (2) ◽  
pp. 023302
Author(s):  
Wei Liu ◽  
Ning Li ◽  
Chun-sheng Weng ◽  
Xiao-long Huang ◽  
Yang Kang
Keyword(s):  
Bubble Dynamics ◽  
Pressure Field ◽  
Gas Jet ◽  
Detonation Tube

The Pressure Field Radiated by Cavitation Bubble in the Grinding Area of Power Ultrasonic Honing

2014 ◽  
Vol 1027 ◽  
pp. 44-47 ◽  
Author(s):  
Xi Jing Zhu ◽  
Ce Guo ◽  
Jian Qing Wang
Keyword(s):  
Radiation Pressure ◽  
Cavitation Bubble ◽  
Bubble Dynamics ◽  
Pressure Field ◽  
Bubble Radius ◽  
Ultrasonic Frequency ◽  
Power Ultrasonic ◽  
Cutting Chatter ◽  
Grinding Mechanism ◽  
Order Of Magnitude

The pressure field induced by cavitaion bubble is responsible for the grinding mechanism and the cutting chatter of power ultrasonic honing. Based on the cavitation bubble dynamics model in the grinding area of power ultrasonic honing, the radiation pressure field of cavitation bubble was established. Experimental results show that the bubble is distributed in the grinding area like honeycomb and the size is about 10μm. Numerical simulation of dynamics and pressure field of cavitation bubble was performed. Numerical results show the dynamic behavior of cavitation bubble presents grow, expend and collapse under an acoustic cycle. However the expansion amplitude of bubble can be decreased and the collapse time can be extended and even collapse after several acoustic cycles with increasing ambient bubble radius. The bubble radiation pressure during collapsing bubble increases with increasing ultrasonic amplitude and ultrasonic frequency. And the pressure value of collapsing bubble is about 10Mpa which is more an order of magnitude than atmospheric pressure.

scholarly journals The Kelvin impulse: application to cavitation bubble dynamics

1988 ◽  
Vol 30 (2) ◽  
pp. 127-146 ◽  
Author(s):  
J. R. Blake
Keyword(s):  
Fluid Mechanics ◽  
Cavitation Bubble ◽  
Bubble Dynamics ◽  
Velocity Potential ◽  
Pressure Field ◽  
Ring Vortex ◽  
Fluid Density ◽  
Cavitation Damage ◽  
Unsteady Fluid ◽  
Image Position

AbstractThe Kelvin impulse is a particularly valuable dynamical concept in unsteady fluid mechanics, with Benjamin and Ellis [2] appearing to be the first to have realised its value in cavitation bubble dynamics. The Kelvin impulse corresponds to the apparent inertia of the cavitation bubble and, like the linear momentum of a projectile, may be used to determine aspect It is defined aswhere ρ is the fluid density, ø is the velocity potential, S is the surface of the cavitation bubble and n is the outward normal to the fluid. Contributions to the Kelvin impulse may come from the presence of nearby boundaries and the ambient velocity and pressure field. With this number of mechanisms contributing to its development, the Kelvin impulse may change sign during the lifetime of the bubble. After collapse of the bubble, it needs to be conserved, usually in the form of a ring vortex. The Kelvin impulse is likely to provide valuable indicators as to the physical properties required of boundaries in order to reduce or eliminate cavitation damage. Comparisons are made against available experimental evidence.

Bubble Dynamics Under Forced Oscillation in Microgravity Environment

2009 ◽  
Author(s):  
Mohammad Movassat ◽  
Nasser Ashgriz ◽  
Markus Bussmann
Keyword(s):  
Bubble Dynamics ◽  
Pressure Field ◽  
Forced Oscillation ◽  
Translational Motion ◽  
Density Ratio ◽  
Nonlinear Behavior ◽  
Forced Vibrations ◽  
Microgravity Environment ◽  
Shape Oscillation ◽  
Bubble Interaction

Two-dimensional numerical simulation of bubble dynamics in microgravity is performed employing a Volume of Fluid (VOF) solver. Shape oscillation and deformation of bubbles under forced vibration are studied. Coupling between the oscillatory translational motion and shape deformation results in nonlinear behavior of bubbles at high amplitudes and frequencies. As a result of oscillation of the buoyancy force, the pressure field around the bubbles oscillates and bubbles interact with each other. Effect of vibration frequency and amplitude and liquid to gas density ratio on the shape of bubbles and bubble-bubble interaction is studied. It is shown that the shape of the bubbles in response to the forced vibrations mainly depends on the acceleration of the vibration.

Inertially driven inhomogeneities in violently collapsing bubbles: the validity of the Rayleigh–Plesset equation

2002 ◽  
Vol 452 ◽  
pp. 145-162 ◽  
Author(s):  
HAO LIN ◽  
BRIAN D. STOREY ◽  
ANDREW J. SZERI
Keyword(s):  
Wave Motion ◽  
Bubble Dynamics ◽  
Pressure Field ◽  
Numerical Solutions ◽  
Stokes Equations ◽  
Spatial Inhomogeneity ◽  
Navier Stokes ◽  
Navier Stokes Equations ◽  
Self Consistency ◽  
Good Agreement

When a bubble collapses mildly the interior pressure field is spatially uniform; this is an assumption often made to close the Rayleigh–Plesset equation of bubble dynamics. The present work is a study of the self-consistency of this assumption, particularly in the case of violent collapses. To begin, an approximation is developed for a spatially non-uniform pressure field, which in a violent collapse is inertially driven. Comparisons of this approximation show good agreement with direct numerical solutions of the compressible Navier–Stokes equations with heat and mass transfer. With knowledge of the departures from pressure uniformity in strongly forced bubbles, one is in a position to develop criteria to assess when pressure uniformity is a physically valid assumption, as well as the significance of wave motion in the gas. An examination of the Rayleigh–Plesset equation reveals that its solutions are quite accurate even in the case of significant inertially driven spatial inhomogeneity in the pressure field, and even when wave-like motions in the gas are present. This extends the range of utility of the Rayleigh–Plesset equation well into the regime where the Mach number is no longer small; at the same time the theory sheds light on the interior of a strongly forced bubble.

Bubble dynamics and deformation in microgravity

2001 ◽  
Vol 11 (PR6) ◽  
pp. Pr6-231-Pr6-238
Author(s):  
C. Colin ◽  
J. Fabre
Keyword(s):  
Bubble Dynamics
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