高速对颗粒介质的影响:传统惯性阻力模型的分解
Manish Kumar Mandal1, Saikat Roy1
1Department of Chemical Engineering, IIT Ropar, Rupnagar, Punjab, 140001, India. saikat.roy@iitrpr.ac.in.
Soft matter
|January 4, 2024
概括
高速对颗粒状介质的冲击揭示了声脉冲,而不是指数式衰变. 这些脉冲重组了力链,挑战了现有的阻力模型,并通过塑性变形显示了能量消耗.
科学领域:
- 物理 物理学 物理
- 材料科学 材料科学 材料科学
- 地质物理学 地质物理学
背景情况:
- 目前对颗粒状介质影响的研究仅限于低冲击速度 (0.0001-0.001).
- 传统的宏观阻力模型对于高速撞击场景是不够的.
研究的目的:
- 在颗粒状介质中研究高速撞击动态 (撞击速度与声速比为0.01-1).
- 将模拟数据与现有的宏观拖动模型进行比较.
- 在高速撞击期间分析粒子尺度现象.
主要方法:
- 在高速冲击下对颗粒状介质的数值模拟.
- 将模拟结果与已建立的阻力模型进行比较.
- 分析力链,位移和速度场的时空演变.
主要成果:
- 传统的阻力模型在高冲击速度下失败.
- 拖拉力不能像之前建议的那样分为静态和惯性组成部分.
- 观测到远程传播和干扰声脉冲的直接证据.
- 声脉冲诱导大规模的力量链网络重组和穿越堵塞状态.
- 由于力链重定位而观察到的塑料消散和能量消散.
结论:
- 高速冲击会在颗粒状介质中产生传播的声脉冲.
- 颗粒状介质动态重组力链,以管理冲击负载.
- 空间维度显著影响到峰值冲击力的缩放.
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