Marschall Theodore A, Teitel S
Department of Physics and Astronomy, University of Rochester, Rochester, New York 14627, USA.
Phys Rev E. 2020 Mar;101(3-1):032907. doi: 10.1103/PhysRevE.101.032907.
We use numerical simulations to study the flow of athermal, frictionless, soft-core two-dimensional spherocylinders driven by a uniform steady-state simple shear applied at a fixed volume and a fixed finite strain rate γ[over ̇]. Energy dissipation is via a viscous drag with respect to a uniformly sheared host fluid, giving a simple model for flow in a non-Brownian suspension with Newtonian rheology. We study the resulting spatial structure of the sheared system, and compute correlation functions of the velocity, the particle density, the nematic order parameter, and the particle angular velocity. Correlations of density, nematic order, and angular velocity are shown to be short ranged both below and above jamming. We compare a system of size-bidisperse particles with a system of size-monodisperse particles, and argue how differences in spatial order as the packing increases lead to differences in the global nematic order parameter. We consider the effect of shearing on initially well ordered configurations, and show that in many cases the shearing acts to destroy the order, leading to the same steady-state ensemble as found when starting from random initial configurations.
我们使用数值模拟来研究在固定体积和固定有限应变率γ[上加˙]下施加均匀稳态简单剪切驱动的无热、无摩擦、软核二维球柱体的流动。能量耗散是通过相对于均匀剪切的主体流体的粘性阻力实现的，从而给出了一个具有牛顿流变学的非布朗悬浮液中流动的简单模型。我们研究了剪切系统产生的空间结构，并计算了速度、粒子密度、向列序参数和粒子角速度的相关函数。密度、向列序和角速度的相关性在堵塞以下和以上均显示为短程。我们将大小双分散粒子系统与大小单分散粒子系统进行比较，并论证随着堆积增加，空间有序性的差异如何导致全局向列序参数的差异。我们考虑剪切对初始有序构型的影响，并表明在许多情况下，剪切作用会破坏有序性，导致与从随机初始构型开始时相同的稳态系综。
