水蒸气在超疏水表面上的冷凝传热  

CONDENSATION HEAT TRANSFER OF STEAM ON SUPER-HYDROPHOBIC SURFACES

作　　者：宋永吉[1] 任晓光[1] 任绍梅[1] 王虹[1] 

机构地区：[1]北京石油化工学院化学工程系,北京102617

出　　处：《工程热物理学报》2007年第1期95-97,共3页Journal of Engineering Thermophysics

基　　金：北京市教育委员会科技发展计划项目资助(No.2002KJ067)

摘　　要：用高温裂解法在紫铜基底上制备了疏水性碳纳米管膜,通过对此碳纳米管膜进行氟化处理,改善了表面的疏水性。在室温下,实验测得水在这种表面上的接触角在90°-130°之间。以水蒸气为冷凝介质的冷凝传热实验表明,水蒸气在超疏水纳米材料表面上能形成较好的滴状冷凝,冷凝传热膜系数可达40000 W／(m2·K)。与纯粹膜状冷凝相比,冷凝传热系数提高3-4倍。分析表明,此碳纳米管膜所产生的附加热阻只占冷凝传热热阻的千分之一,对冷凝传热膜系数的影响可以忽略。A kind of hydrophobic surfaces with aligned carbon nanotube film structure was prepared by pyrolysis of metal phthalocyanines. Fluoroalkylsilane treatment improved the hydrophobicity of the films. Experimental measurement indicated that the contact angles of water on the super-hydrophobic surfaces ranged from 90° to 130° under room temperature. Steam condensation heat transfer experiment was carried out at atmospheric pressure and perfect dropwise condensation was observed on the super-hydrophobic surfaces. The condensation heat transfer film coefficient reached to 40000 W/（m2·K） under experimental conditions. This value is usually 3 to 4 times of that of filmwise condensation heat transfer. Analysis revealed that the auxiliary heat transfer resistance caused by the nanotube film was only 0.1 percent contrast to dropwise condensation heat transfer resistant. Therefore, the effect of the auxiliary heat transfer resistance of the film on total condensation heat transfer was negligible.

关 键 词：冷凝传热 滴状冷凝 超疏水性 炭纳米管膜 

分 类 号：TK124[动力工程及工程热物理—工程热物理]