在振荡的流动中,球形颗粒的模式形成
T J J M van Overveld1, H J H Clercx1, M Duran-Matute1
1Fluids and Flows group and J.M. Burgers Center for Fluid Mechanics, Department of Applied Physics and Science Education, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
Physical review. E
|September 19, 2023
概括
球形粒子在振荡的流动中自组织成链条或带. 它们的间距取决于流体动力学,而带宽受粒子覆盖和流量条件的影响.
科学领域:
- 流体动力学 流体动力学
- 软物质物理学 软物质物理学
- 粒子的自我组织
背景情况:
- 了解液体流中的粒子自我组织对于各种应用至关重要.
- 之前的研究已经探索了简单流中的粒子行为,但复杂的振荡流带来了独特的挑战.
- 水力动力学相互作用在决定粒子排列中的作用需要进一步研究.
研究的目的:
- 为了研究球形粒子在一个封闭的盒子内的振荡流中的自我组织.
- 确定控制粒子链和带的形成的关键参数.
- 阐明对粒子自我组织负责的潜在水力动力学机制.
主要方法:
- 在振荡盒中对粒子行为的实验研究.
- 互补的数值模拟与完全解决的粒子周围的流动.
- 分析粒子间距和带宽作为振荡条件和限制的函数.
主要成果:
- 粒子自组织成一个粒子厚的链条或多个粒子宽的带,垂直于振荡.
- 正规链间距由粒子-流体相对外游长度确定,以粒子直径 (A_{r}/D) 规范化.
- 带宽取决于A_{r}/D和粒子覆盖率 (φ);从链到带的过渡可以准确地预测.
结论:
- 水力动力相互作用,特别是稳定流动流中的,驱动粒子自我组织.
- 吸引力和排斥力的平衡要求有规律的链距离.
- 在更高的A_{r}/D的短距离吸引力稳定了更宽的频段,为粒子排列提供了全面的参数图.
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