降落冲击中缩放的统一理论:力量和最大扩散直径
Vatsal Sanjay1, Detlef Lohse1,2
1University of Twente, Physics of Fluids Department, Max Planck Center Twente for Complex Fluid Dynamics, and J. M. Burgers Center for Fluid Dynamics, P.O. Box 217, 7500AE Enschede, Netherlands.
Physical review letters
|March 28, 2025
概括
这项研究揭示了滴滴撞击力和传播如何取决于韦伯数 (动能) 和奥内索尔格数 (粘度). 一个新的理论解释了这些动态在一个庞大的参数范围,突出显示粘度.
科学领域:
- 流体动力学 流体动力学
- 类风病学 类风病学 类风病学
- 表面科学是一门学科.
背景情况:
- 滴水冲击动态是由滴水的速度,大小和材料特性决定的.
- 关键特征包括冲击力和最大扩散半径.
- 了解无维参数如韦伯数 (We) 和奥内索尔格数 (Oh) 的影响至关重要.
研究的目的:
- 为了研究滴滴撞击力和最大传播半径对We和Oh的依赖.
- 开发一个统一的理论方法,滴水冲击动态.
- 为了探索一个广泛的参数范围:1≤We≤103和10−3≤Oh≤102.
主要方法:
- 在一个广泛的参数空间中进行了直接的数值模拟.
- 开发了一个新的理论框架,灵感来自现有的流理论.
- 分析了不同冲击阶段的能量消耗率.
主要成果:
- 开发的理论量化解释了最大冲击力和扩散直径的We和Oh依赖.
- 该理论在广泛的参数中是有效的.
- 澄清了粘性消散在低粘度滴滴冲击中的重要作用.
结论:
- 一个统一的理论成功地解释了滴滴撞击动态.
- 该研究提供了对冲击力和扩散的定量预测.
- 它挑战了关于粘度在低OH冲击中的作用的先前假设.
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