论文标题
碰撞活性液滴的对齐和散射
Alignment and scattering of colliding active droplets
论文作者
论文摘要
活性液滴在其表面发出化学溶质,以改变其局部界面张力。他们利用将溶质对流传输到由此产生的Marangoni流向自行词的非线性耦合。这种游泳液滴本质上是反化妆的,被自己的化学唤醒或邻居所击退。最近,使用特定的双球方法对成对液滴相互作用产生的反弹动力学进行了详细分析。在这里,我们扩展了此分析,并提出了一个通用碰撞的简化模型,以表征斜滴碰撞的比对和散射特性及其对集体液滴动力学的潜在影响。当液滴直接相互作用时,观察到液滴轨迹的系统对齐,并源于碰撞期间液滴化学唤醒的有限时间重排。对于更通用的碰撞,无论液滴直接相互作用还是通过其化学唤醒相互作用,都会观察到复杂而多样的动态状态,从而导致显着的散射。
Active droplets emit a chemical solute at their surface that modifies their local interfacial tension. They exploit the nonlinear coupling of the convective transport of solute to the resulting Marangoni flows to self-propel. Such swimming droplets are by nature anti-chemotactic and are repelled by their own chemical wake or their neighbours. The rebound dynamics resulting from pairwise droplet interactions was recently analysed in detail for purely head-on collisions using a specific bispherical approach. Here, we extend this analysis and propose a reduced model of a generic collision to characterise the alignment and scattering properties of oblique droplet collisions and their potential impact on collective droplet dynamics. A systematic alignment of the droplets' trajectories is observed for symmetric collisions, when the droplets interact directly, and arises from the finite-time rearrangement of the droplets' chemical wake during the collision. For more generic collisions, complex and diverse dynamical regimes are observed, whether the droplets interact directly or through their chemical wake, resulting in a significant scattering.