Biased swimming cells do not disperse in pipes as tracers: A population model based on microscale behaviour
Biased swimming cells do not disperse in pipes as tracers: A population model based on microscale behaviour
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DOI：
10.1063/1.4772189
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发表时间：
2012-05
影响因子：
4.6
通讯作者：
R. Bearon;M. Bees;O. A. Croze
中科院分区：
文献类型：
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作者：
R. Bearon;M. Bees;O. A. Croze
目前，人们对藻类和其他微生物悬浮液的生物技术开发建模很感兴趣，许多生物反应器都是管状设计。利用广义Taylor弥散理论，建立了垂直管流中微生物悬浮液的种群水平游动-平流-扩散模型。特别是，作用于单个细胞的重力和粘性扭矩的组合可以影响它们的游泳行为，这被称为回转。这通常导致细胞悬浮液中的局部细胞漂移和扩散。在管道中的流动中，穿过流线的少量径向漂移可以对细胞的有效轴向漂移和扩散产生重大影响。我们提出了一个Galerkin方法来计算局部平均游泳速度和扩散张量的基础上的局部剪切任意流量。在弱剪切和强剪切的极限下，用渐近结果验证了该方法的有效性。我们解决了由此产生的游泳-平流-扩散.
There is much current interest in modelling suspensions of algae and other micro-organisms for biotechnological exploitation, and many bioreactors are of tubular design. Using generalized Taylor dispersion theory, we develop a population-level swimming-advection-diffusion model for suspensions of micro-organisms in a vertical pipe flow. In particular, a combination of gravitational and viscous torques acting on individual cells can affect their swimming behaviour, which is termed gyrotaxis. This typically leads to local cell drift and diffusion in a suspension of cells. In a flow in a pipe, small amounts of radial drift across streamlines can have a major impact on the effective axial drift and diffusion of the cells. We present a Galerkin method to calculate the local mean swimming velocity and diffusion tensor based on local shear for arbitrary flow rates. This method is validated with asymptotic results obtained in the limits of weak and strong shear. We solve the resultant swimming-advection-diffusion...