液滴对颗粒床的影响:滴惯性和颗粒大小的影响
Alexandre Pontier1, Sarah Blosse1, Sylvain Viroulet1
1Institut de Mécaniques des Fluides de Toulouse (IMFT), Université de Toulouse, CNRS, 31400 Toulouse, France. laurent.lacaze@imft.fr.
Soft matter
|July 2, 2025
概括
这项研究揭示了液滴撞击如何在颗粒状物质中形成石坑. 石坑的大小取决于滴滴特性和粒度大小,有一个新的无维数统一观测.
科学领域:
- 流体动力学 流体动力学
- 颗粒物理 颗粒物理
- 冲击力学 冲击力学
背景情况:
- 了解液滴对颗粒表面的影响对于各种科学和工程应用至关重要.
- 之前的研究发现了基于撞击速度和滴滴大小的模式,但对火山口形成动态缺乏统一的理解.
研究的目的:
- 为了研究从液滴撞击密集的颗粒床上的火山口形成的模式.
- 分析无维参数如弗罗德数 (Fr),韦伯数 (We) 和粒径比 (d_g/D) 对石口径的影响.
- 通过结合能量消散机制,开发一个统一的框架来预测火山口的大小.
主要方法:
- 实验研究液滴对聚钢珠床的影响.
- 分析了各种各样的撞击速度,直径和颗粒大小的石坑尺寸.
- 使用弗劳德数,韦伯数和尺寸比来描述冲击模式的维度分析.
主要成果:
- 识别了由无维数 (Fr,We,d_g/D) 控制的不同影响机制.
- 观察到低无维数的火山口直径的We^(1/4) 缩放,在更高的We.转变为d_g/D主导.
- 引入了一个新的无维数 (UE141),通过计算粒粒摩擦和滴滴惯性来统一火山口大小数据.
结论:
- 石坑的大小强烈依赖于粒与滴的大小比率 (d_g/D) 和滴滴撞击特征.
- 这项研究强调了火山口形成过程中从特征转向能量方法的转变.
- 新定义的无维数 (UE141) 成功地将实验数据缩在一起,为火山口的形成提供了一个统一的模型.
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