中国物理B ›› 2019, Vol. 28 ›› Issue (1): 14703-014703.doi: 10.1088/1674-1056/28/1/014703

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Molecular-dynamics investigation of the simple droplet critical wetting behavior at a stripe pillar edge defect

Xiaolong Liu(刘小龙), Chengyun Hong(洪成允), Yong Ding(丁勇), Xuepeng Liu(刘雪朋), Jianxi Yao(姚建曦), Songyuan Dai(戴松元)   

  1. 1 Beijing Key Laboratory of Novel Thin-Film Solar Cells & Beijing Key Laboratory of Energy Safety and Clean Utilization, North China Electric Power University, Beijing 102206, China;
    2 Renewable Energy School, North China Electric Power University, Beijing 102206, China
  • 收稿日期:2018-09-20 修回日期:2018-11-07 出版日期:2019-01-05 发布日期:2019-01-05
  • 通讯作者: Xiaolong Liu, Songyuan Dai E-mail:xl.liu@ncepu.edu.cn;sydai@ncepu.edu.cn
  • 基金资助:

    Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0202401), the National Natural Science Foundation of China (Grant No. 61705066), and the Fundamental Research Funds for the Central Universities, China (Grant No. 2017MS028).

Molecular-dynamics investigation of the simple droplet critical wetting behavior at a stripe pillar edge defect

Xiaolong Liu(刘小龙)1,2, Chengyun Hong(洪成允)2, Yong Ding(丁勇)1,2, Xuepeng Liu(刘雪朋)1,2, Jianxi Yao(姚建曦)1,2, Songyuan Dai(戴松元)1,2   

  1. 1 Beijing Key Laboratory of Novel Thin-Film Solar Cells & Beijing Key Laboratory of Energy Safety and Clean Utilization, North China Electric Power University, Beijing 102206, China;
    2 Renewable Energy School, North China Electric Power University, Beijing 102206, China
  • Received:2018-09-20 Revised:2018-11-07 Online:2019-01-05 Published:2019-01-05
  • Contact: Xiaolong Liu, Songyuan Dai E-mail:xl.liu@ncepu.edu.cn;sydai@ncepu.edu.cn
  • Supported by:

    Project supported by the National Key Research and Development Program of China (Grant No. 2016YFA0202401), the National Natural Science Foundation of China (Grant No. 61705066), and the Fundamental Research Funds for the Central Universities, China (Grant No. 2017MS028).

摘要:

The microscopic stripe pillar is one of the most frequently adopted building blocks for hydrophobic substrates. However, at high temperatures the particles on the droplet surface readily evaporate and re-condense on the pillar sidewall, which makes the droplet highly unstable and undermines the overall hydrophobic performance of the pillar. In this work, molecular dynamics (MD) simulation of the simple liquid at a single stripe pillar edge defect is performed to characterize the droplet's critical wetting properties considering the evaporation-condensation effect. From the simulation results, the droplets slide down from the edge defect with a volume smaller than the critical value, which is attributed to the existence of the wetting layer on the stripe pillar sidewall. Besides, the analytical study of the pillar sidewall and wetting layer potential field distribution manifests the relation between the simulation parameters and the degree of the droplet pre-wetting, which agrees well with the MD simulation results.

关键词: molecular-dynamics simulation, simple liquid, single stripe, critical wetting

Abstract:

The microscopic stripe pillar is one of the most frequently adopted building blocks for hydrophobic substrates. However, at high temperatures the particles on the droplet surface readily evaporate and re-condense on the pillar sidewall, which makes the droplet highly unstable and undermines the overall hydrophobic performance of the pillar. In this work, molecular dynamics (MD) simulation of the simple liquid at a single stripe pillar edge defect is performed to characterize the droplet's critical wetting properties considering the evaporation-condensation effect. From the simulation results, the droplets slide down from the edge defect with a volume smaller than the critical value, which is attributed to the existence of the wetting layer on the stripe pillar sidewall. Besides, the analytical study of the pillar sidewall and wetting layer potential field distribution manifests the relation between the simulation parameters and the degree of the droplet pre-wetting, which agrees well with the MD simulation results.

Key words: molecular-dynamics simulation, simple liquid, single stripe, critical wetting

中图分类号:  (Computational methods in fluid dynamics)

  • 47.11.-j
47.11.Mn (Molecular dynamics methods) 47.10.Fg (Dynamical systems methods)