在随机和定期分布的圆柱柱表面均湿时的能量消散
Pawan Kumar1, Paul Mulvaney2, Dalton J E Harvie1
1Multiphysics Fluid Dynamics Group, Department of Chemical Engineering, University of Melbourne, Parkville, Melbourne, 3010, Victoria, Australia.
Journal of colloid and interface science
|December 30, 2023
概括
在粗的表面上接触角歇斯底里可以使用稀释缺陷模型进行预测. 接触线运动期间的能量消散是理解和预测各种表面湿行为的关键.
科学领域:
- 表面科学是一门学科.
- 湿度研究 湿度研究
- 流体动力学 流体动力学
背景情况:
- 粗的表面在自然界和工业中无处不在.
- 接触角歇斯底里是影响表面湿透性的关键参数.
- 对于粗表面的歇斯底里现有模型需要改进.
研究的目的:
- 在随机和结构化粗表面上研究接触角歇斯底里.
- 为了验证稀释缺陷模型用于描述hysteresis.
- 开发基于能量消耗的歇斯底里斯的预测方程.
主要方法:
- 在具有随机和周期性微柱粗的表面上测量接触角歇斯底里.
- 测试了一系列液体,其固有的接触角度从33.8°到112.0°.
- 开发了一种在随机表面上平均接触角的方法.
主要成果:
- 对于粗度诱导的能量消散的衍生相关性.
- 提出了一个方程,用于预测在均湿 (温泽尔) 下随机表面的前进和后退接触角.
- 定义了替代湿状态 (hemiwicking,分进,分退,Cassie) 的条件及其有效范围.
- 提出了一个"集群"概念来解释结构表面上较高的hysteresis.
结论:
- 在粗表面上的接触角歇斯底里可以使用稀释缺陷模型来预测.
- 能量消散是歇斯底里的一个关键因素.
- 该研究提供了一个框架,用于理解和预测粗表面的湿模式.
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