Wetting property of smooth and textured hydrophobic surfaces under condensation condition  

作　　者：HAO PengFei LV CunJing YAO ZhaoHui NIU FengLei 

机构地区：[1]Department of Engineering Mechanics,Tsinghua University [2]State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources,North China Electric Power University

出　　处：《Science China(Physics,Mechanics & Astronomy)》2014年第11期2127-2132,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11072126,11272176,91326108 and 51206042);the Foundation of Stake Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(Grant No.LAPS14018)

摘　　要：Static and dynamic wetting behaviors of sessile droplet on smooth,microstructured and micro/nanostructured surface under condensation condition are systematically studied.In contrast to the conventional droplet wetting on such natural materials by dropping,we demonstrate here that when dropwise condensation occurs,the sessile droplet will transit from the Cassie-Baxter wetting state to the Wenzel wetting state or partial Cassie-Baxter wetting state on the microstructured surface or the micro/nanostructured surface,which leads to a strong adhesion between the droplet and the substrate.In contrast,the apparent contact angle and the sliding angle on the smooth surface changes a little before and after the condensation because of small roughness.Theoretical analysis shows that the roughness factor controls the adhesion force of the droplet during condensation,and a theoretical model is constructed which will be helpful for us to understand the relationship between the adhesion force and the geometry of the surface.Static and dynamic wetting behaviors of sessile droplet on smooth,microstructured and micro/nanostructured surface under condensation condition are systematically studied.In contrast to the conventional droplet wetting on such natural materials by dropping,we demonstrate here that when dropwise condensation occurs,the sessile droplet will transit from the Cassie-Baxter wetting state to the Wenzel wetting state or partial Cassie-Baxter wetting state on the microstructured surface or the micro/nanostructured surface,which leads to a strong adhesion between the droplet and the substrate.In contrast,the apparent contact angle and the sliding angle on the smooth surface changes a little before and after the condensation because of small roughness.Theoretical analysis shows that the roughness factor controls the adhesion force of the droplet during condensation,and a theoretical model is constructed which will be helpful for us to understand the relationship between the adhesion force and the geometry of the surface.

关 键 词：condensation hydrophobic roughness droplet systematically wetting apparent nanotube structured diameters 

分 类 号：O485[理学—固体物理]