标题： 活性向列体对可变形物体或边界的响应：弹性变形和锚定诱导的流动 显示英文标题

标题： Active nematic response to a deformable body or boundary: elastic deformations and anchoring-induced flow

摘要： 浸没于向列型液晶中的物体干扰了液体的分子排列，并增加了其储存的弹性能量。在活性向列相中，流体成分还会在体相流体中产生应力。通过引入浸没物体或边界，仅靠锚定边界条件就能触发大规模流动——平衡状态下由活性应力产生的全局压力会瞬间在整个系统中释放。然后，流体对该表面施加粘性、弹性和活性应力，如果表面可变形，则可能导致表面形变。我们研究了二维情况下放置在活性向列相中的线弹性体的形变和应力。利用复变量技术，得到了流场、取向场、表面牵引力以及物体形变的精确表达式。根据活性埃里克森数、锚定条件和物体材料属性的不同，识别了弹性应力驱动和活性应力驱动形变之间的定性差异，从而提出了一种在活性各向异性环境中测量机械应力的新方法。还讨论了流动剖面、外部限制和锚定诱导的搅拌现象。 显示英文摘要

摘要： A body immersed in a nematic liquid crystal disturbs the fluid's preferred molecular configuration and increases its stored elastic energy. In an active nematic, the fluid components also generate a stress in the bulk fluid. By introducing either an immersed body or boundary, a large scale flow can be triggered due to anchoring boundary conditions alone -- a global pressure built by active stresses at equilibrium is instantly released everywhere. The fluid then imposes viscous, elastic, and active stresses on such surfaces which, if compliant, may result in a surface deformation. We study the deformations and stresses of a linearly elastic body placed in an active nematic in two dimensions. Using complex variables techniques, exact expressions for the fluid flow, director field, surface tractions, and body deformation are derived. Qualitative differences between elastic and active stress-driven deformations are identified, depending on an active Ericksen number, anchoring conditions, and body material properties, thereby suggesting a new method for measuring mechanical stresses in active anisotropic environments. Flow profiles, external confinement, and anchoring-induced stirring are also addressed.