吸引力增强的摩擦在体物质中的出现
Berend van der Meer1,2,3, Taiki Yanagishima3,4, Roel P A Dullens2,3
1Wageningen University & Research, Physical Chemistry and Soft Matter, Stippeneng 4, 6708 WE, Wageningen, The Netherlands.
Physical review letters
|March 7, 2025
概括
体系统中的摩擦力来自粒子协调. 增加协调使粒子运动呈指数级减慢,通过吸引力控制摩擦.
科学领域:
- 软物质物理学 软物质物理学
- 结合体科学 结合体科学
- 材料科学 材料科学 材料科学
背景情况:
- 由于热波动和短暂的接触,了解颗粒物材料中的微观摩擦是具有挑战性的.
- 粒子间摩擦对宏观材料性质的作用尚未完全理解.
研究的目的:
- 直接将粒子级摩擦停止与合体系统中的局部协调联系起来.
- 研究粒子间相互作用如何影响摩擦接触的形成.
- 为了建立摩擦,协调和粒子间相互作用之间的定量关系.
主要方法:
- 使用了一个有吸引力的体模型系统.
- 采用简单的计算机模拟来模拟粒子间相互作用和接触形成.
- 分析了粒子级动态和协调数.
主要成果:
- 揭示了粒子定向动态的指数减速,随着协调数的增加.
- 证明摩擦相互作用强度可以通过不同的吸引力强度来调整.
- 建立了连接摩擦,协调和粒子间相互作用的定量关系.
结论:
- 粒子协调直接决定了合体系统中微观摩擦的出现.
- 粒子间的吸引力强度是调整摩擦力的关键参数.
- 这项工作为通过粒子间摩擦来设计颗粒物质特性提供了基础.
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