在垂直磁场下对撞击铁流体液滴最大传播的数值模拟
Jia-Cai Huang1, Tian-Yang Han2, Jie Zhang1
1School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an 710049, China.
Langmuir : the ACS journal of surfaces and colloids
|September 26, 2024
概括
这项研究模拟了铁流体液滴在磁场下的表面上传播. 磁场可以减少滴水的传播,但最初的滴水形状会影响最终的直径.
科学领域:
- 流体动力学 流体动力学
- 磁动力学 磁动力学
- 表面科学是一门科学.
背景情况:
- 铁流体滴滴动力学在微流体学和材料科学中至关重要.
- 了解外界场下的滴水冲击行为对于控制沉积和湿至关重要.
- 现有的模型往往缺乏对磁场对传播的影响的全面分析.
研究的目的:
- 开发一种理论模型,预测垂直磁场下的铁流体滴撞击干燥表面的最大扩散直径.
- 为了研究磁场强度,冲击速度和初始接触角度对滴滴传播的影响.
- 为在高磁场下建立最大扩散直径的缩放定律.
主要方法:
- 基于能量平衡原理的理论建模.
- 模型预测与数值模拟结果的比较.
- 通过假定动能转化为磁能来推导一个缩放定律.
- 用粘性消散和毛细血管效应进行插曲,用于通用重新缩放.
主要成果:
- 该模型准确地预测了滴滴传播,与数值发现有很好的一致性.
- 增加磁场强度会减少球形撞击滴的最大传播直径.
- 自由落下的水滴,在撞击前形成一个圆形形状,由于平衡的表面能量和磁效应,其最大传播直径几乎没有变化.
- 在高磁场下的最大扩散直径的缩放定律得到了推导和验证.
结论:
- 理论能量平衡模型准确地预测铁流体液滴在磁场下扩散.
- 磁力显著影响传播动力学,其对粘性和毛细血管力的支配性取决于场强度.
- 该模型提供了一个平衡的公式来预测最大扩散直径,适用于各种冲击条件.
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