通过抛光和氧化刻蚀方法在基体壁面形成微米和纳米尺度的微观结构,然后制备十八烷基硫醇分子自组装膜,从而得到空气中表观接触角为160°的SAM-1表面和空气中表观接触角为116°的SAM-2表面.实验研究了常压条件下两类表面的滴状冷凝传热特性.结果表明两种表面都能够有效提高冷凝传热效果.但是,具有表面纳米结构的SAM-1表面的滴状冷凝传热特性低于SAM-2表面.分析了纳米结构和液固自由能差效应对滴状冷凝传热影响的共同作用机理.
Fine polish and oxidation etching method are applied to prepare micro--and nano--structures on copper surfaces.After that,self-assembled monolayers(SAMs)of n-octadecyl mercaptan are coated on.In air circumstance,the contact angle of water on the nano-structured surface(SAM-1)is 160°and that on the finely polished coated surface fSAM-21 is 116..Both coated surfaces have promoted dropwise condensation very well.The condensation heat transfer performance of the SAM-2 is much better than that of the SAM-1.The coordinated effe!cts of difierence of surface free energy between nanostructure and liquid-solid on the dropwise condensation heat transfer are analyzed.
参考文献
[1] | MA Xue-Hu;ROSE J;xu Dun-Qi et al.Advances in Dropwise Condensation Heat Transfer:Chinese Research[J].Chemical Engineering Journal,2000,78:87-93. |
[2] | 马学虎;陈嘉宾;徐敦颀 等.蒸汽冷凝形态的表面自由能差判据[J].化工学报,2002,53(05):557-560. |
[3] | MA Xue-Hu;CHEN Xiao-Feng;BAI Tao et al.A New Mechanism for Condensation heat Transfer Enhaneement:Effect of the Surface Free Energy Difference of Condensate and Solid Surface[J].Journal of Enhanced Heat Transfer,2004,11(04):257-265. |
[4] | LAN Zhong;MA Xue-Hu;zHANG Yu et al.Theoretical Study of Dropwise Condensation Heat Transfer:Effect of the Liquid-solid Surface Free Energy Difrerence[J].Journal of Enhanced Heat Transfer,2009,16(01):61-71. |
[5] | MA Xue-Hu;LAN Zhong;ZHOU Xing-Dong.Effect of Surface-Free-Energy-Difference on Condensation Char-acteristic Curves of Binary Mixture of Steam and Ethanol Vapor[A].United States of America,2006:663-669. |
[6] | Cassie A B;Baxter S .Wettability of Porous Surfaces[J].Transactions of the Faraday Society,1944,40:546-551. |
[7] | Wier KA;McCarthy TJ .Condensation on ultrahydrophobic surfaces and its effect on droplet mobility: Ultrahydrophobic surfaces are not always water repellant[J].Langmuir: The ACS Journal of Surfaces and Colloids,2006(6):2433-2436. |
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