电场作用下纳米流体液滴在超疏水热表面蒸发特性的研究  

Evaporation Characteristics for Sessile Nanofluid Droplets on Superhydrophobic Heated Surfaces in the Electric Field

作　　者：刘海龙[1] 刘志伟 吴洪雷 郑诺 王军锋[1] LIU Hai-Long;LIU Zhi-Wei;WU Hong-Lei;ZHENG Nuo;WANG Jun-Feng(School of Energy and Power Engineering,Jiangsu University,Zhenjiang 212013,Jiangsu,China)

机构地区：[1]江苏大学能源与动力工程学院,镇江212013

出　　处：《工程热物理学报》2022年第3期704-711,共8页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51876086)。

摘　　要：本文研究了平行电场中超疏水热表面上氧化石墨烯纳米流体液滴的蒸发特性。利用可视化技术捕捉了液滴接触角、接触直径及瞬态相界面的变化。实验发现平行电场能够将液滴沿电势梯度方向拉伸成椭球状,并可以调控蒸发过程中液滴接触直径的变化过程及大小。当液滴接触直径收缩比减小至某一临界值后,将出现一种新的蒸发模式:接触角与接触直径均保持不变的极限蒸发模式。电场强度的改变将使不同质量浓度氧化石墨烯纳米流体液滴的蒸发模式产生显著差异。强电场作用将促使纳米颗粒的沉积形貌趋于球状。该研究为基于蒸发相变制备球形颗粒提供创新思路与技术手段。In this study, the evaporation characteristics of sessile droplets with graphene oxide nanofluids on heated superhydrophobic surface subjected to parallel electric field have been investigated experimentally. We employed visualization techniques to capture the evolutions of droplet contact angle, contact line and transient interface morphology. It is found that the droplet could be stretched along the gradient direction of the electric potential into a nearly spheroid. And the electric field would affect the variation of droplet contact diameter. As the shrinkage ratio of contact diameter approaching a critical value, a novel evaporation mode is emerged during the evaporation.At this stage, the contact angle and contact diameter droplet remain constant along with the evaporating, which is defined as the extreme mode. The enhancement of the electric field would change the evaporation models of nanofluid droplets with various mass concentrations. The stronger applied electric field could promote the graphene oxide to form the spherical sediments. This research proposed the innovative method and technique to manufacture spherical nanoparticles by means of phase transition principle.

关 键 词：液滴蒸发 电场 超疏水表面 纳米流体 

分 类 号：TK121[动力工程及工程热物理—工程热物理]