软硬球体3D混合物的颗粒流
Bo Fan1,2, Tivadar Pongó3, Joshua A Dijksman2,4
1Institute for Solid State Physics and Optics, HUN-REN Wigner Research Centre for Physics, Budapest H-1525, Hungary. borzsonyi.tamas@wigner.hu.
Soft matter
|April 22, 2025
概括
将少量的硬粒添加到软粒中,可以大大改变仓库流量. 颗粒流中的这种突然转变是由于在仓库开口附近的应力变化,而不是摩擦.
科学领域:
- 颗粒物理 颗粒物理
- 材料科学 是一种材料科学.
背景情况:
- Silo 的排放动态对于工业过程至关重要.
- 由于粒子相互作用,理解颗粒流动行为是复杂的.
研究的目的:
- 调查混合硬摩擦和软低摩擦珠对仓库排放率的影响.
- 确定导致流动行为突然变化的潜在机制.
主要方法:
- 从圆柱形筒子中排放颗粒混合物的实验调查.
- 数字模拟用于模拟流动动力学和应力条件.
- 准静态剪切测试和拖拉力测量以分析摩擦性能.
主要成果:
- 100%的软粒显示填充高度依赖的流量;100%的硬粒显示高度独立的流量.
- 仅添加20%的硬颗粒就会使流速曲线的斜率下降50-70%.
- 数字模拟表明,孔区域的应力条件对混合物组成高度敏感.
结论:
- 仓库排放速率的突然变化主要是由应力条件的变化驱动的,而不是摩擦消散.
- 摩擦性质随着硬粒度的增加而略有增加,但不能解释观察到的流速过渡.
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