Stochastic model of oscillatory diffusion for colloidal particles in a fixed porous bed
Stochastic model of oscillatory diffusion for colloidal particles in a fixed porous bed
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DOI：
10.1016/j.ces.2021.116993
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发表时间：
2021-08-14
影响因子：
4.7
通讯作者：
Marshall, Jeffrey S.
中科院分区：
文献类型：
--
作者：
Curran, Kelly;Marshall, Jeffrey S.
填充床内孔隙中的胶体颗粒在施加的振荡流(如与声场相关的振荡流)作用下来回运动。颗粒的扩散运动是振荡运动的间歇性阻碍的结果，我们认为这是颗粒被填充床孔隙过滤的结果。我们考虑了一个经过实验验证的随机模型，该模型需要在振荡状态和捕获状态之间进行一系列转换，在振荡状态下，颗粒随着流体的流动而振荡，在捕获状态下，颗粒被固定在床上。本文考察了该随机模型对不同参数的敏感性，并将随机模型对扩散系数的预测与基于连续时间随机游走(CTRW)理论的解析解的预测进行了比较。这些结果与纳米颗粒渗透到生物膜、药物胶囊渗透到人体组织以及饱和土壤中的微塑性传输等应用相关。CO 2021爱思唯尔有限公司版权所有。
Colloidal particles in the pore spaces within a packed bed move back and forth in response to an imposed oscillatory flow, such as that associated with an acoustic field. The diffusive motion of the particles results from intermittent hindering of the oscillatory motion, which we assume to result from particle filtration by the packed bed pore spaces. We consider an experimentally-validated stochastic model that entails a series of transitions between an oscillatory state, where the particle oscillates with the fluid flow, and a captured state, where the particle is held fixed in the bed. The paper examines sensitivity of this stochastic model to different parameters and compares the stochastic model predictions for diffusion coefficient with predictions of an analytical solution based on continuous-time random walk (CTRW) theory. The results are relevant to applications such as nanoparticle penetration into biofilms, drug capsule penetration into human tissue, and microplastic transport within saturated soil. CO 2021 Elsevier Ltd. All rights reserved.