Q -tensor model for undulatory swimming in lyotropic liquid crystal polymers
Q -tensor model for undulatory swimming in lyotropic liquid crystal polymers
复制标题
溶致液晶聚合物中波动游动的 Q 张量模型
DOI：
10.1017/jfm.2021.531
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发表时间：
2021
影响因子：
3.7
通讯作者：
Gao, Tong
中科院分区：
文献类型：
--
作者：
Lin, Zhaowu;Chen, Sheng;Gao, Tong
微生物可能在各向异性流体（例如液晶）中表现出丰富的游泳行为，这些流体具有方向依赖的物理和流变特性。在这里，我们构建了一个二维计算模型来研究微型游泳器在刚性棒状液晶聚合物溶液中的波动游泳机制。我们使用 Doi 张量模型描述流体相，并将游泳者视为有限长度的柔性纤维，在身体曲率上施加传播行波。流固相互作用通过浸入边界法解决。与牛顿流体中的游动动力学相比，我们观察到溶致液晶聚合物中游动运动增强和延迟的非牛顿行为。我们通过分析近体流场和聚合力分布以及泰勒游泳片理想化模型的渐近分析来揭示推进机制。
Microorganisms may exhibit rich swimming behaviours in anisotropic fluids, such as liquid crystals, which have direction-dependent physical and rheological properties. Here we construct a two-dimensional computation model to study the undulatory swimming mechanisms of microswimmers in a solution of rigid, rodlike liquid crystal polymers. We describe the fluid phase using Doi's -tensor model, and treat the swimmer as a finite-length flexible fibre with imposed propagating travelling waves on the body curvature. The fluid–structure interactions are resolved via an immersed boundary method. Compared with the swimming dynamics in Newtonian fluids, we observe non-Newtonian behaviours that feature both enhanced and retarded swimming motions in lyotropic liquid crystal polymers. We reveal the propulsion mechanism by analysing the near-body flow fields and polymeric force distributions, together with asymptotic analysis for an idealized model of Taylor's swimming sheet.