微/纳双尺度复合多孔结构对沸腾传热性能的影响  

Effect of Micro/Nano Dual-scale Composite Porous Structure on Boiling Heat Transfer Performance

作　　者：冉令鸿 郎中敏[1] 吴刚强[1] 高向阳 RAN Linghong;LANG Zhongmin;WU Gangqiang;GAO Xiangyang(School of Chemistry and Chemical Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,Inner Mongolia,China)

机构地区：[1]内蒙古科技大学化学与化工学院,内蒙古自治区包头市014010

出　　处：《中国电机工程学报》2022年第7期2630-2637,共8页Proceedings of the CSEE

基　　金：国家自然科学基金项目(21868022)。

摘　　要：采用溶胶–凝胶法制备了纳米孔隙尺度的珊瑚状结构氧化铜粉体,通过还原烧结法制得微纳米双尺度复合多孔传热表面(micro-nanodual-scale composite porous heat transfer surface,MNPS),研究其结构对沸腾传热性能的影响,并对其沸腾过程可视化进行了验证。实验发现:该表面颗粒间孔隙直径在1~2μm之间,颗粒内存在约为100nm且均匀分布的珊瑚状网络孔道。在实验范围内,以乙醇为沸腾工质,纳米孔道尺度在80~130nm,微米孔道尺度在1~1.5μm(micron pores accounted for 0.15,MP0.15)时,MNPS传热性能最佳,约为光滑表面的7倍,是微米孔道尺度在0.8~1.0μm(MP0.00)的1.4倍。由沸腾过程(charge coupled device,CCD)可视化得出,MNPS微米孔道可显著增加活性核化位点,提高气泡核化密度;MNPS纳米孔道在毛细吸力作用下,可增强液相回流,延缓膜沸腾的形成。2种尺度孔隙协同可降低气泡逸出与液相回流之间的阻力,实现强化传热。The sol-gel method was used to prepare the nano-pore-scale coral-like structured copper oxide powder, and the micro-nano dual-scale composite porous heat transfer surface(MNPS) was prepared by the reduction sintering method.Also, the influence of its structure on the boiling heat transfer performance was studied, and the visualization of its boiling process was verified. The experiment found that the diameter of the pores between the particles on the surface was between 1 and 2 μm, and there were coral-like network pores of about 100 nm and uniformly distributed in the particles. In the experimental range, using ethanol as the boiling working medium, when the nano-pore size was 80~130 nm, micron, the pore size is 1~1.5 μm(MP0.15), and the heat transfer performance of MNPS was the best, which as about 7 times that of the smooth surface and 1.4 times that of the micron pore size of 0.8~1.0μm(MP0.00). The visualization of boiling process shows that MNPS micron pore can significantly increase the active nucleation site and bubble nucleation density, and MNPS nano-pore can enhance liquid phase reflux and delay the formation of membrane boiling under the action of capillary suction. The coordination of pores of the two scales can reduce the resistance between bubble escape and liquid phase reflux and realize enhanced heat transfer.

关 键 词：沸腾传热 强化传热 多孔介质 双尺度结构 沸腾过程可视化 

分 类 号：TM61[电气工程—电力系统及自动化]