微纳液滴在粗糙固体壁面上的电润湿特性  

Electro-wetting Characteristics of a Nano-droplet on Rough Solid Substrate

作　　者：宋粉红[1,2] 马龙 范晶[1] 陈奇成[1] 王刚[1] SONG Fen-Hong;MA Long;FAN Jing;CHEN Qi-Cheng(School of Energy and Power Engineering,Northeast Dianli University,Jilin 132012,China;School of Energy and Power Engineering,Chongqing University,Key Laboratory of Low-grade Energy Utilization Technologies and Systems of Ministry of Education,Chongqing 400030,China)

机构地区：[1]东北电力大学能源与动力工程学院,吉林132012 [2]重庆大学动力工程学院,低品位能利用技术及系统教育部重点实验室,重庆400030

出　　处：《工程热物理学报》2019年第9期1963-1968,共6页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助(No.51606032);吉林省优秀青年人才基金项目资助(No.20190103065JH)

摘　　要：本文构建了微纳液滴在粗糙硅壁面上润湿铺展的分子动力学模拟模型,研究电场作用下纳米水液滴在粗糙形状不同、粗糙因子相同的固体壁面上的电润湿特性。首先纳米水液滴在无电场作用下达到平衡状态,然后施加不同强度的电场,根据密度分布得出液滴轮廓,统计各工况下接触角变化。研究结果表明,在弱电场作用下,液滴在固体壁面上呈现对称润湿特性;当Ex=0.5 V/nm时,纳米液滴沿电场方向被拉伸并且在立方矩阵形表面上完全拉伸呈条状,说明粗糙壁面形状对微纳液滴的润湿行为起着重要作用。Molecular dynamic simulation method was employed to investigate the wetting behaviors of nano-droplet on rough solid substrates with same roughness factor.An equilibrium state of nano-droplet spreading on solid surface was reached firstly and then the external electric field was applied to the system to study the effect of roughness shapes on the electro-wetting profiles.The contact angle taken to represent the wetting property was obtained by fitting the contour of the droplet.Results show that the droplet undergoes a symmetric spreading on the solid substrate under a weak electric field.When the electric field strength is E_x= 0.5 V/nm,nano-droplet was stretched in the direction of electric field and even to be strip-shaped on the pillar solid substrate.It indicates that the roughness shape of the solid substrate plays an important role in the electro-wetting behaviors of a droplet on a rough solid surface.

关 键 词：电润湿 接触角 粗糙因子 分子动力学 

分 类 号：TK123[动力工程及工程热物理—工程热物理]