一个蔓延的滴滴的结
Ganesh Prabhu Komaragiri1, Abrar Ahmed1, Prashant R Waghmare1
1interfacial Science and Surface Engineering Lab (iSSELab), Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa, Ontario K1S 5B6, Canada.
Journal of colloid and interface science
|June 4, 2025
概括
冰冷表面的滴滴结是由能量平衡和无维数控制的. 在较低的温度下更快的核化矛盾地延迟了由于接触线运动停止而导致的完全结.
科学领域:
- 流体动力学 流体动力学
- 热传递是一种热传递.
- 材料科学是一种材料科学.
背景情况:
- 湿度预测依赖于整体能量平衡 (OEB) 方法,考虑惯性,粘性,表面,引力能量和热传递.
- 假设一个关键的斯蒂芬数与快速核化/复苏和延迟的总滴水结有关,与三相接触线 (TPCL) 运动停止有关.
研究的目的:
- 用喷气式沉积技术研究预冷表面上的滴水浸湿性和结动力学.
- 为了验证整体能量平衡 (OEB) 方法用于预测滴滴行为.
- 探索基板温度和材料对滴滴结动力学的影响.
主要方法:
- 喷射式滴滴沉积技术以消除外部身体力量.
- 在-20°C至0°C的温度下使用了具有不同导热性的基板 (铜,,黄铜,不钢).
- 采用高速和红外热成像来捕捉滴滴动态和热谱.
主要成果:
- OEB模型准确地预测了实验观测结果,验证了假设.
- 无维数 (韦伯,雷诺兹,邦德,斯蒂芬,佩克莱) 被确定为液滴传播的关键规则参数.
- 超冷却效应被发现是可以忽略不计的喷气式沉积方法.
- 滴滴的传播速度随着基质温度的增加而增加;较低的温度导致传播速度较慢.
- 总结时间在-20°C最长,尽管在这种温度下核形成最快.
结论:
- 整体能量平衡 (OEB) 方法,结合关键无维数,有效地预测了预冷表面上的滴滴湿度和结.
- 喷射式沉积减少了超冷却,从而可以更清楚地观察基本的结现象.
- 基质温度对滴滴传播的速度和冷完成的总体时间都有显著影响,并观察到反向关系.
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