PDMS表面上的液滴蒸发实验研究

夏雪莲; 郑旭; 黄先富; 周金枝; 余迎松

doi:10.21656/1000-0887.370358

PDMS表面上的液滴蒸发实验研究

doi: 10.21656/1000-0887.370358

¹湖北工业大学土木建筑与环境学院力学系, 武汉 430068;²非线性力学国家重点实验室(中国科学院); 中国科学院力学研究所, 北京 100190

基金项目: 国家自然科学基金（面上项目）(11572114)

详细信息

作者简介:
夏雪莲(1992—)，女，硕士生(E-mail: wyb569183976@qq.com);余迎松(1979—)，男，副教授，博士(通讯作者. E-mail: yuystm@mail.hbut.edu.cn).

中图分类号: O363.2
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出版历程
- 收稿日期: 2016-11-17
- 修回日期: 2017-03-06
- 刊出日期: 2017-05-15

Experimental Investigation of Evaporating Sessile Droplets on PDMS Surface

¹Department of Mechanics, School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, P.R.China;²State Key Laboratory of Nonlinear Mechanics(Chinese Academy of Sciences); Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, P.R.China

Funds: The National Natural Science Foundation of China（General Program）(11572114)

摘要

摘要: 利用粒子跟踪测速(particle tracking velocimetry, PTV) 技术，研究了聚二甲基硅氧烷（polydimethylsiloxane, PDMS）表面上的液滴蒸发行为.发现固液界面上的荧光微球首先向固液界面中心移动，而后发生运动反转，向三相接触线移动.其原因是由于接触线钉扎时接触线附近的蒸发通量较小，从而引起向液滴中心的流动，这种流动将微球带向液滴中心.理论分析了三相接触线的移动特征，发现其移动速度理论值与实验值在同一量级，而移动加速度的实验值较理论值偏大，造成这种偏差的原因是三相接触线处的荧光微球削弱了基底对三相接触线的钉扎作用.
- 液滴 /
- 蒸发 /
- PDMS /
- 接触线 /
- PTV技术
Abstract: Evaporation of sessile water droplets on polydimethylsiloxane (PDMS) surface was experimentally studied with the particle tracking velocimetry (PTV) technique. The fluorescent microspheres at the solid-liquid interface first moved towards the center and then back to the contact line. Because the evaporative flux near the contact line is less than that far from the line, there will be a capillary flow towards the center when the contact line is pinned. Such a flow will carry microspheres towards the center. Moving characteristics of the contact line were also investigated. It is found that the theoretical values of the moving velocity at different moments in the CCA stage is of the same order with the experimental values. However, the experimental moving accelerations were much larger than the theoretical ones because the microspheres at the contact line weaken the interaction between the PDMS surface and the contact line.
- droplet /
- evaporation /
- PDMS /
- contact line /
- PTV technique

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