Peristaltic particle transport using the lattice Boltzmann method
Peristaltic particle transport using the lattice Boltzmann method
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DOI：
10.1063/1.3111782
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发表时间：
2009-05-01
影响因子：
4.6
通讯作者：
Chen, Shiyi
中科院分区：
文献类型：
--
作者：
Connington, Kevin;Kang, Qinjun;Chen, Shiyi
蠕动运输是指一类内部流体流动，其中柔性容纳壁的周期性变形引起不可忽略的流体运动。当施加有利的压力梯度无效或不可能或希望避免所输送的混合物与机械运动部件之间的接触时，它是一种用于在管或通道中输送流体和浸没的固体颗粒的机构。蠕动运输发生在许多生理情况下，并具有多种工业应用。我们使用晶格玻尔兹曼方法重点研究二维通道中宏观粒子的蠕动传输。我们系统地研究了系统相关无量纲参数的变化对粒子输运的影响。我们发现，在其他结果中，雷诺数的增加实际上会导致粒子传输的轻微增加，以及随着壁变形的增加，粒子的运动仅变得非负的情况。我们检查系统表现出特殊的流体捕获现象时的粒子行为。在这些情况下，颗粒本身可能会被捕获，随后以波速传输，这是在没有有利压力梯度的情况下最大可能的传输。最后，我们分析颗粒的存在如何影响流体中的应力、压力和耗散，希望确定剪切敏感颗粒蠕动运输的首选工作条件。我们发现，靠近河道喉部的剪切应力水平最为危险。我们建议，剪切敏感颗粒应在发生捕获的条件下运输，因为颗粒通常位于无害剪切应力水平的区域。
Peristaltic transport refers to a class of internal fluid flows where the periodic deformation of flexible containing walls elicits a non-negligible fluid motion. It is a mechanism used to transport fluid and immersed solid particles in a tube or channel when it is ineffective or impossible to impose a favorable pressure gradient or desirous to avoid contact between the transported mixture and mechanical moving parts. Peristaltic transport occurs in many physiological situations and has myriad industrial applications. We focus our study on the peristaltic transport of a macroscopic particle in a two-dimensional channel using the lattice Boltzmann method. We systematically investigate the effect of variation of the relevant dimensionless parameters of the system on the particle transport. We find, among other results, a case where an increase in Reynolds number can actually lead to a slight increase in particle transport, and a case where, as the wall deformation increases, the motion of the particle becomes non-negative only. We examine the particle behavior when the system exhibits the peculiar phenomenon of fluid trapping. Under these circumstances, the particle may itself become trapped where it is subsequently transported at the wave speed, which is the maximum possible transport in the absence of a favorable pressure gradient. Finally, we analyze how the particle presence affects stress, pressure, and dissipation in the fluid in hopes of determining preferred working conditions for peristaltic transport of shear-sensitive particles. We find that the levels of shear stress are most hazardous near the throat of the channel. We advise that shear-sensitive particles should be transported under conditions where trapping occurs as the particle is typically situated in a region of innocuous shear stress levels.