论文标题
液体液体界面附近的微晶状体的动力学，粘度差
Dynamics of microswimmers near a liquid-liquid interface with viscosity difference
论文作者
论文摘要
材料跨液体界面的运输对于活细胞而言是普遍存在的，并且在药物输送和许多工业过程中也是至关重要的一步。界面两侧存在的流体通常具有不同的粘度。我们提出了一个物理模型，用于使用Navier-Stokes Flow的计算机模拟来解决的柔软且可穿透的接口附近的Microswimmers的动力学。文献中包含对类似的等无效流体系统的研究，其中两种流体具有相同的粘度。在这里，我们将其扩展到更普遍的情况，即它们具有不同的粘度。我们研究了流体粘度比对微晶状体运动模式的影响。我们发现游泳者系统地重新定向了含有较低粘度流体的区域。最终，这有望使游泳者的行为表现，好像他们更倾向于在低粘度流体中游泳。此外，除了在等异情系统中已经报道的游泳类型，即弹跳，滑动和穿透性，我们观察到了悬停的运动，在该运动中，强力拉杆与一定距离的界面平行于界面平行，这与靠近实心墙附近此类游泳者的动态相一致。
Transport of material across liquid interfaces is ubiquitous for living cells and is also a crucial step in drug delivery and in many industrial processes. The fluids that are present on either side of the interfaces will usually have different viscosities. We present a physical model for the dynamics of microswimmers near a soft and penetrable interface that we solve using computer simulations of Navier-Stokes flows. The literature contains studies of similar isoviscous fluid systems, where the two fluids have the same viscosity. Here we extend this to the more general case where they have different viscosities. We investigate the effect of the fluid viscosity ratio on the movement patterns of microswimmers. We find that swimmers systematically reorientate towards the region containing the lower viscosity fluid. Ultimately this is expected to drive the swimmers to behave as if they are more inclined to swim in low viscosity fluids. Furthermore, in addition to the types of swimming already reported in the isoviscous system, i.e. bouncing, sliding and penetrating, we observed a hovering motion, in which strong pullers swim parallel to the interface with a certain distance, which is consistent with the dynamics of such swimmers near the solid wall.
