论文标题
Quincke辊的集体运动，具有完全分辨的流体动力学
Collective Motion of Quincke Rollers with Fully Resolved Hydrodynamics
论文作者
论文摘要
Quincke辊是一个独特的活动粒子，由于垂直于板上施加的均匀DC电场产生的扭矩，可以在平板上自由运行和滚动。涉及许多此类颗粒的系统表现出各种集体动力学，例如无序气体，极性液体和活性晶体状态。我们对一个三维系统进行了直接数值模拟，该系统包含许多自动旋转颗粒，以明确解决旋转颗粒之间的流体动力相互作用。集体运动取决于在介电颗粒，颗粒的面积和颗粒间吸引力的强度上引起的偶极矩的大小。我们发现，高度有序的极性液态因高密度下旋转颗粒之间的流体动力相互作用而破坏了稳定：近场润滑相互作用在远场效应上占主导地位，因为颗粒间的分离变短。
A Quincke roller is a unique active particle that can run and tumble freely on a flat plate due to the torque generated by a uniform DC electric field applied perpendicular to the plate. A system involving many such particles exhibits a variety of collective dynamics, such as the disordered gas, polar liquid, and active crystal states. We performed direct numerical simulations of a three-dimensional system containing many self-rotating particles to explicitly resolve the hydrodynamic interactions among rotating particles. The collective motion depends on the magnitude of the dipole moments induced on the dielectric particles, the area fraction of particles, and the strength of interparticle attraction. We find that the highly ordered polar liquid state is destabilized by the hydrodynamic interaction between rotating particles at high densities: the near-field lubrication interaction becomes dominant over far-field effects as the interparticle separation becomes shorter.
