有结构壁面上液滴运动特征的耗散粒子动力学模拟  

Movement of a droplet on a structured substrate:A dissipative particle dynamics simulation study

作　　者：姚祎[1] 周哲玮[1] 胡国辉[1] 

机构地区：[1]上海大学上海市应用数学和力学研究所 上海市力学在能源工程中的应用重点实验室,上海200072

出　　处：《物理学报》2013年第13期355-361,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11272197);教育部博士点基金(批准号:20103108110004);上海市高校创新团队资助的课题~~

摘　　要：本文采用耗散粒子动力学方法,研究了恒定外力驱动下液滴在有结构壁面上的运动过程.通过研究液滴在通过壁面结构时前缘接触点和前进角的变化,分析了液滴的运动特征.研究结果表明,在不同润湿性或不同外力驱动下,存在使液滴运动最快的"最优"壁面结构,并对其机理进行了讨论.本文还探讨了壁面润湿性、热涨落以及外力对液滴运动状态的影响.The last decade has witnessed the explosive development of microfluidic systems. Droplet manipulation is one of the crucial technologies in design and optimization of microfluidic devices. In the present study, dissipative particle dynamics is applied to investigate the movement of a liquid droplet actuated by a constant force on structured substrate with different wetting properties ranging from hydrophilic to hydrophobic. By monitoring the variation of the advancing contact angle and the front position of droplet, the characteristics of the droplet motion is analyzed in detail. Results indicate that there exists an optimal structure for which the droplet has a largest speed. Additionally, the influences of wettability gradient, thermal fluctuation and external force are discussed. We find thermal fluctuation is helpful for the movement of droplet.

关 键 词：微流体 有结构壁面 润湿性 耗散粒子动力学(DPD) 

分 类 号：O35[理学—流体力学]