吸引控制的扭矩组织和摩擦颗粒物质中的旋转态
Attraction-controlled torque organization and rotational states in frictional granular matter
- Tokyo University of Science（东京科学大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究通过数值模拟发现，颗粒间吸引力虽不直接施加扭矩，但通过重组摩擦接触网络，控制应力状态、扭矩组织和旋转，影响二维摩擦颗粒材料的宏观流变学。
AI中文摘要：
在本研究中，我们通过数值模拟探究了二维摩擦颗粒材料中颗粒间吸引力如何影响应力传递、扭矩组织和颗粒旋转。尽管吸引力是一种中心力，对颗粒不施加直接扭矩，但它强烈地改变了接触网络和颗粒旋转。吸引力产生低速率应力状态，并在干系统的剪切增稠区域附近选择高应力状态，而几乎不改变高速率增稠状态。通过分解剪切应力，我们发现直接的吸引贡献仅占总应力的一部分，而排斥贡献则显著增强。吸引力增加了配位数和扭矩幅度，并可能逆转局部扭矩符号相关性。在低堆积分数和中等剪切速率下，会出现应力崩溃状态，尽管存在有限的接触网络，但扭矩和旋转被强烈抑制。这些结果表明，吸引力通过重组摩擦接触网络来控制宏观流变学。
英文摘要：
In this study, we numerically investigate how interparticle attraction affects stress transmission, torque organization, and particle rotation in a two-dimensional frictional granular material. Although the attraction is a central force and exerts no direct torque on the particles, it strongly modifies the contact network and particle rotation. Attraction produces a low-rate stress state and selects the high-stress state near the shear-thickening regime of the dry system, while leaving the high-rate thickened state almost unchanged. By decomposing the shear stress, we find that the direct attractive contribution accounts for only a fraction of the total stress, while the repulsive contribution is strongly enhanced. Attraction increases the coordination number and torque amplitude and can reverse the local torque-sign correlation. At low packing fractions and intermediate shear rates, a stress-collapse state emerges with strongly suppressed torque and rotation despite a finite contact network. These results show that attraction controls macroscopic rheology through reorganization of the frictional contact network.
