在强制颗粒流动过程中,压力配置文件的自我相似性
María Victoria Ferreyra1, Luis A Pugnaloni1,2, Diego Maza3
1Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad Nacional de La Pampa, Uruguay 151, 6300 Santa Rosa, La Pampa, Argentina.
Physical review. E
|February 17, 2024
概括
测量结果显示,在排放过程中,堆基地的垂直应力显著增加,特别是增加重量. 应力配置文件随着堆尺寸和增加的质量而重新扩展,挑战了当前的颗粒式流量模型.
科学领域:
- 物理 物理学 物理
- 工程 工程师 工程师 工程师
背景情况:
- 颗粒状材料表现出复杂的流动行为.
- 了解仓库中的应力分布对于设计和安全至关重要.
研究的目的:
- 在放电过程中测量和分析圆柱体仓库底部的垂直应力概况.
- 为了研究颗粒柱高度,筒子直径和添加质量对应力分布的影响.
主要方法:
- 在平底圆柱体仓库的底部对垂直应力 (σ) 的实验测量.
- 通过一个以重量为中心的孔径通过一个应用过重的排放.
- 基于颗粒列高度 (z),筒子直径 (D) 和超重质量 (W) 的数据重新缩放.
主要成果:
- 气底部的垂直应力 (σ) 在排放结束时显著增加.
- σ(z,D,W) 数据在重新缩放为z/D的函数时崩.
- 辐射应力形状 σ(r) 具有自我相似性,可以根据不同的实验条件进行重新缩放.
结论:
- 该研究提出了一个可重新扩展的模型,用于排放筒仓的垂直应力分布.
- 虽然可以预测功能依赖性,但定量准确性仍然是一个挑战.
- 结果需要重新评估目前通过孔径进行颗粒流动的模型.
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