中国空间科学技术

中国空间科学技术 ›› 2025, Vol. 45 ›› Issue (4): 61-69.doi: 10.16708/j.cnki.1000-758X.2025.0058

• 微重力流体科学及其空间应用专题 • 上一篇    下一篇

不同重力条件约束下液滴的电润湿输运动力学研究

霍晓智1,2,3，王晴1,3，顾君苹2，王战涛4，王庆功2,*，于强1,*   

  1. 1.中国科学院国家空间科学中心，北京100190
    2.中国空间技术研究院 钱学森空间技术实验室，北京100094
    3.中国科学院大学 计算机科学与技术学院，北京100049
    4.中山职业技术学院 机电工程学院，广东528400
  • 收稿日期:2024-01-11 修回日期:2024-06-11 录用日期:2024-07-05 发布日期:2025-07-22 出版日期:2025-08-01

Dynamics of droplet transport by electrowetting in different gravity levels

HUO Xiaozhi1,2,3，WANG Qing1,3，GU Junping2，WANG Zhantao4，WANG Qinggong2,*，YU Qiang1,*   

  1. 1.National Space Science Center, Chinese Academy of Sciences，Beijing 100190,China
    2.Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology，Beijing 100094，China
    3.School of Computer Science and Technology，University of Chinese Academy of Sciences，Beijing 100049，China
    4.School of Mechanical & Electronic Engineering, Zhongshan Polytechnic, Zhongshan 528400, China
  • Received:2024-01-11 Revision received:2024-06-11 Accepted:2024-07-05 Online:2025-07-22 Published:2025-08-01

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摘要： 采用电润湿效应可以实现液滴的界面控制与流体输运，且它具有响应时间短、功耗低、过程可逆等优点，在地面及空间微重力环境下具有广泛应用前景。基于电润湿效应的液滴输运主要靠电场提供表面电润湿力，一般忽略重力的影响；但当液滴需要沿着重力方向输运或克服重力实现界面控制时，重力的作用不可忽略。面向空间应用，针对不同重力约束条件对电润湿输运动力学的影响开展研究。设计了电润湿作用液滴输运系统，建立了电润湿力驱动的液滴输运数值模拟模型；通过捕捉液滴前边缘位置来设置电极的开关状态，形成了瞬态电润湿作用连续驱动液滴运动的方法。首先研究了液滴在零重力场下电润湿连续输运动力学及其界面行为规律；进而考虑不同重力场/逆重力场条件，获得不同重力水平对液滴电润湿输运过程的影响。研究结果表明，该电润湿系统能够实现液滴的连续快速输运，输运速度达到0.28m/s左右；液滴输运速度随施加电压增加而线性增加；接触线滑移速度受液滴与电极间接触面积的影响，当液滴体积增大时，液滴输运速度显著减小；随着液滴体积增大，重力的影响增强，但所施加的电压范围能够克服-2g的重力水平，实现液滴抗重力输运。研究获得了不同重力条件对液滴电润湿输运行为的约束规律，可为空间变重力环境下液滴收集与输运提供理论基础。

关键词: 电润湿, 液滴输运, 不同重力条件, 数值模拟, 动力学

Abstract: Electrowetting is an effective method for interface manipulation and fluid transport, and it has great application prospects both on Earth and in space due to the advantages of fast response, low power consumption and controllable path. Previously, the influence of gravity is ingnored in the study of the dynamics of droplet transport by electrowetting. However, the gravity must be taken into account when droplets are transported along the direction of gravity or against gravity. Therefore, the dynamics of droplet transport by electrowetting in different gravity levels is studied for space application. In this work, a droplet transport system by electorwentting is designed, and a simulated method of droplet transport by electrowetting is established. In addition, a method of continuous droplet transport is proposed by capturing droplet’s front edge to set activation states of electrodes. Then, the dynamics of long-distance droplet transport by electrowetting is studied in a zero-gravity environment, and the influence of gravity level on droplet transport by electrowetting is analyzed. The continuous and rapiad transport of droplet is achieved using this eletrocwetting system. The simulated results show that the transport velocity of droplet reaches about 0.28m/s. The droplet transport velocity increases almost linearly with the applied voltage. The droplet velocity decreases with the droplet size because the large base diameter of the droplet increases the friction between the droplet and the plate. The gravity’s direction and level affect the droplet’s motion significantly. The droplet deforms under the gravity effect. However, the electrowetting force is still able to overcome the gravity level of -2g, and the electrowetting system shows a good anti-gravity ablity. The constraint laws of droplet transport by electrowetting in different gravity levels are obtained, which provide theoretical basis for droplet collection and tansport in space environment.

Key words: electrowetting, fluid transport, gravity level, numerial simulation, dynamics