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Abstract We study the collapse and expansion of a cavitation bubble in a deformable porous medium. We develop a continuum-scale model that couples compressible fluid flow in the pore network with the elastic response of a solid skeleton. Under the assumption of spherical symmetry, our model can be reduced to an ordinary differential equation that extends the Rayleigh–Plesset equation to bubbles in soft porous media. The extended Rayleigh–Plesset equation reveals that finite-size effects lead to the breakdown of the universal scaling relation between bubble radius and time that holds in the infinite-size limit. Our data indicate that the deformability of the porous medium slows down the collapse and expansion processes, a result with important consequences for wide-ranging phenomena, from drug delivery to spore dispersion.
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Vortex Fluid Flow for Generation of Hydrodynamic Cavitation Aimed at Enhancing Manufacturing Processes
The energy emanating from hydrodynamic cavitation can play a significant role in enhancing manufacturing processes that utilize fluid medium as a force transmitter, a lubricant, or as a carrier. The fluid flow characteristics in a vortex cavitation generator is studied to determine how bubbles could be transported to a target location prior to implosion. Preliminary CFD simulations and experimental results have shown that the cavitating fluid stream exhibits a swirl flow pattern causing the cavitating stream to remain at the core of the stream. This phenomenon opens avenues for developing mechanisms for controlling and transporting cavitating bubbles to target locations prior to implosion.
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- Award ID(s):
- 2043325
- PAR ID:
- 10404705
- Editor(s):
- Castagne, Sylvie; Dimov, Stefan; Kulinsky, Laurence; Dohda, Kuniaki
- Date Published:
- Journal Name:
- World Congress on Nano and Micro Manufacturing 2022
- Volume:
- 2022
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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