在高雷诺兹数的流中对吊带事件的定量预测
Tobias Bätge1,2, Itzhak Fouxon3,4, Michael Wilczek1,5
1Max Planck Institute for Dynamics and Self-Organization (MPIDS), Am Faßberg 17, 37077 Göttingen, Germany.
Physical review letters
|August 18, 2023
概括
流显著增强了云中的水滴碰撞. 这项研究使用速度梯度历史量化了"吊带事件",揭示了它们在滴水生长和雨水形成中的关键作用.
科学领域:
- 流体动力学 流体动力学
- 大气科学 大气科学
- 流的研究研究流.
背景情况:
- 流加剧了温暖云层中的滴滴碰撞,这对于雨形成至关重要.
- 粒子碰撞取决于流程历史和罕见的间歇性流结构.
- 了解这些事件是模拟云微物理学的关键.
研究的目的:
- 制定一项针对影响滴滴碰撞的乱"吊带事件"的定量标准.
- 研究速度梯度历史在粒子碰撞中的作用.
- 分析流间歇性对滴滴生长的影响.
主要方法:
- 在流中粒子路径的理论分析.
- 流速度梯度的数值模拟.
- 基于速度梯度张数的最小实自值的定量标准.
- 斯托克斯和雷诺兹数依赖性的分析.
主要成果:
- 串行事件创建的问题减少到一个1D本地化问题.
- 速度梯度张量控制的最小实本固有值控制了子的创建.
- 在高的雷诺兹数中,对于小的斯托克斯数,sling事件会增强一个数量级.
- 通过完全解析的流模拟证实了预测.
结论:
- 流的间歇性显著影响滴滴碰撞增长.
- 开发的标准为粒子碰撞动态提供了新的理解.
- 这些发现与模拟云中的雨滴形成有关.
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