在剪切颗粒材料中压力独立率的微机械起源
1Indian Institute of Science, Department of Chemical Engineering, Bangalore 560012, India.
Physical review letters
|May 2, 2025
概括
颗粒状材料由于粒子级动量流动而表现出速率独立的应力. 反复的阻塞-屈服动态解释了剪切颗粒流中的应力波动和宏观应力行为.
科学领域:
- 类风病学 类风病学 类风病学
- 颗粒物理 颗粒物理
- 柔软的物质 软的物质
背景情况:
- 剪切颗粒材料中的宏观应力是独立于速率的.
- 微观的动量流量与剪切速率成比例.
- 显微和宏观行为之间的联系仍然不清楚.
研究的目的:
- 研究取决于速率的微观动量流和取决于速率的宏观应力之间的关系.
- 解释颗粒状材料中巨大的应力波动的起源.
主要方法:
- 对缓慢切割颗粒材料的应力波动的分析.
- 粒子运动量传输的特征.
- 干扰-屈服动态的建模.
主要成果:
- 确定了反复出现的阻塞-屈服动态作为应力波动的来源.
- 证明在阻塞过程中变形是弹性的,在屈服过程中以快速爆发的形式发生.
- 建立了这些动态和宏观应力的速率独立性之间的联系.
结论:
- 这项研究为颗粒材料的速率独立应力提供了基本的解释.
- 堵塞-收益力学对于理解颗粒性形学至关重要.
- 应力波动是与材料对剪切反应相关的固有特征.
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