Leng Yu, Vlachos Pavlos P, Juanes Ruben, Gomez Hector
School of Mechanical Engineering, Purdue University, 585 Purdue Mall, West Lafayette, IN 47907, USA.
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
PNAS Nexus. 2022 Aug 18;1(4):pgac150. doi: 10.1093/pnasnexus/pgac150. eCollection 2022 Sep.
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.
我们研究了可变形多孔介质中空化泡的坍塌与膨胀。我们建立了一个连续介质尺度模型，该模型将孔隙网络中的可压缩流体流动与固体骨架的弹性响应耦合起来。在球对称假设下，我们的模型可以简化为一个常微分方程，它将瑞利 - 普莱斯方程扩展到了软多孔介质中的气泡。扩展后的瑞利 - 普莱斯方程表明，有限尺寸效应导致了在无限尺寸极限下成立的气泡半径与时间之间通用标度关系的失效。我们的数据表明，多孔介质的可变形性减缓了坍塌和膨胀过程，这一结果对于从药物输送到孢子扩散等广泛现象具有重要影响。
