论文标题
反应性颗粒之间非线性流体动力相互作用的对称特性
Symmetry properties of nonlinear hydrodynamic interactions between responsive particles
论文作者
论文摘要
通过粘性流体驱动的两个相同稳定力驱动的颗粒可能由于流体动力相互作用而彼此移动。这种相对翻译的存在或不存在对由许多颗粒组成的驱动悬浮液的动力学产生深远影响。我们考虑一对粒子，该粒子在力中线性有序不相互作用。如果系统具有固有特性（例如粒子的形状，它们相对于边界的位置或边界形状），该特性受外部强迫的影响，则可能会出现非线性的水动力相互作用。我们研究了这种非线性反应的一般特性。对粒子交换和力逆转下的对称性的分析导致有关相对翻译的出现和运动的时间可逆性的一般结论。我们在三个特定示例中证明了结论的适用性：（a）平行于壁的两个球体； （b）平行于其连接线驱动的两个可变形物体； （c）两个球沿弯曲路径驱动。时间可逆性的破坏表明，可能使用非线性流体动力相互作用来分散或通过交流力组装颗粒。
Two identical particles driven by the same steady force through a viscous fluid may move relative to one another due to hydrodynamic interactions. The presence or absence of this relative translation has a profound effect on the dynamics of a driven suspension consisting of many particles. We consider a pair of particles which, to linear order in the force, do not interact hydrodynamically. If the system possesses an intrinsic property (such as the shape of the particles, their position with respect to a boundary, or the shape of the boundary) which is affected by the external forcing, hydrodynamic interactions that depend nonlinearly on the force may emerge. We study the general properties of such nonlinear response. Analysis of the symmetries under particle exchange and under force reversal leads to general conclusions concerning the appearance of relative translation and the motion's time-reversibility. We demonstrate the applicability of the conclusions in three specific examples: (a) two spheres driven parallel to a wall; (b) two deformable objects driven parallel to their connecting line; and (c) two spheres driven along a curved path. The breaking of time-reversibility suggests a possible use of nonlinear hydrodynamic interactions to disperse or assemble particles by an alternating force.
