未开发和完全开发的统一流规则 密集的颗粒流向下 粗的斜坡
Yanbin Wu1, Thomas Pähtz1, Zixiao Guo1
1Zhejiang University, Institute of Port, Coastal and Offshore Engineering, Ocean College, Zhoushan, China.
Physical review letters
|February 6, 2025
概括
密集的颗粒流向下倾斜显示复杂的行为. 一个新的流量规则,考虑到流量发展长度,准确地预测各种颗粒材料的自由表面速度.
科学领域:
- 地质物理学 地质物理学
- 流体动力学 流体动力学
- 材料科学 是一种材料科学.
背景情况:
- 对颗粒材料的标准流量规则与实验数据不一致.
- 现有的模型无法考虑流程发展的长度和材料的普遍性.
研究的目的:
- 为密集的颗粒流量开发一个新的,通用的流量规则.
- 为了使实验测量与理论预测相协调.
主要方法:
- 对球体,沙子和混合物的自由表面速度的落下测量.
- 包括沉积物运输统一的维度分析.
- 导出一种新的流量规则,以考虑特征性流量发展长度.
主要成果:
- 导出的流量规则准确地预测了各种颗粒状材料的速度.
- 该规则解决了与标准流量模型的不一致性.
- 确定了特征性流动发展长度 (L) 和非对称速度 (v∞).
结论:
- 一个统一的流量规则可以改善对密集颗粒流量的预测.
- 流程发展长度对于准确的速度建模至关重要.
- 新模型在颗粒状材料中提供了更广泛的适用性.
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