Influences of transversely isotropic rheology and translational diffusion on the stability of active suspensions.
Influences of transversely isotropic rheology and translational diffusion on the stability of active suspensions.
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DOI：
10.1098/rsos.180456
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发表时间：
2018-08
影响因子：
3.5
通讯作者：
Dyson RJ
中科院分区：
文献类型：
--
作者：
Holloway CR;Cupples G;Smith DJ;Green JEF;Clarke RJ;Dyson RJ
自我运动的细长粒子的悬浮是当前非常感兴趣的一个话题，它是“活性物质”的一种形式。例子包括自行推进的细菌、藻类和精子，以及人工游泳者。埃里克森的横观各向同性流体模型(Ericksen 1960 Colloid Polym.SCI。173117-122(DOI：10.1007/bf01502416))将非运动颗粒的悬浮液视为具有演化优先方向的连续体；该模型描述了从细胞外基质、纺织簇状物质到植物细胞壁的各种纤维材料。通过一个具有四个类粘性参数的修正应力张量，引入了指向矢相关的效应。通过与最近的主动悬架模型进行基本联系，我们对Ericksen的模型进行了修正，主要是考虑了自动力，这可以被认为是考虑横观各向同性效应的定向悬架的最简单描述。由于横观各向同性流体表现出改进的流动稳定性这一事实，我们对两种不同的情况--拉长活性颗粒的取向悬浮液和各向同性悬浮液进行了线性稳定性分析。新的方面包括各向异性流变学和平移扩散。通常，各向异性效应增加了小扰动的不稳定性，而平移扩散稳定了一定范围的波方向，在某些情况下，稳定了有限范围的波数，从而强调了各向异性和平移扩散在这些系统中都可以有重要的影响。
Suspensions of self-motile, elongated particles are a topic of significant current interest, exemplifying a form of ‘active matter’. Examples include self-propelling bacteria, algae and sperm, and artificial swimmers. Ericksen's model of a transversely isotropic fluid (Ericksen 1960 Colloid Polym. Sci. 173, 117–122 (doi:10.1007/bf01502416)) treats suspensions of non-motile particles as a continuum with an evolving preferred direction; this model describes fibrous materials as diverse as extracellular matrix, textile tufts and plant cell walls. Director-dependent effects are incorporated through a modified stress tensor with four viscosity-like parameters. By making fundamental connections with recent models for active suspensions, we propose a modification to Ericksen's model, mainly the inclusion of self-motility; this can be considered the simplest description of an oriented suspension including transversely isotropic effects. Motivated by the fact that transversely isotropic fluids exhibit modified flow stability, we conduct a linear stability analysis of two distinct cases, aligned and isotropic suspensions of elongated active particles. Novel aspects include the anisotropic rheology and translational diffusion. In general, anisotropic effects increase the instability of small perturbations, while translational diffusion stabilizes a range of wave-directions and, in some cases, a finite range of wavenumbers, thus emphasizing that both anisotropy and translational diffusion can have important effects in these systems.
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影响因子：
3.7
作者：
Dyson, R. J.;Jensen, O. E.
通讯作者：
Jensen, O. E.
影响因子：
64.8
作者：
Dreyfus, R;Baudry, J;Bibette, J
通讯作者：
Bibette, J
影响因子：
1.9
作者：
Green, J. Edward F.;Friedman, Avner
通讯作者：
Friedman, Avner
DOI：
10.1098/rspa.1922.0078
发表时间：
1922-11-01
期刊：
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES A-CONTAINING PAPERS OF A MATHEMATICAL AND PHYSICAL CHARACTER
影响因子：
--
作者：
Jeffery, GB
通讯作者：
Jeffery, GB
影响因子：
44.1
作者：
Marchetti, M. C.;Joanny, J. F.;Simha, R. Aditi
通讯作者：
Simha, R. Aditi