Steam Condensation Heat Transfer Enhancement on Superhydrophilic-Hydrophobic Hybrid Vertical Surface

doi:10.3901/JME.2018.10.182

Abstract

Abstract: To strengthen steam condensation heat transfer, superhydrophilic-hydrophobic hybrid surface is designed. The effects of parameters such as superhydrophilic grid line spacing and wall undercooling on steam condensation heat transfer are studied and superhydrophilic grid line spacing on hybrid surface is 1.5 mm, 2.5 mm and 3.5 mm respectively. The heat transfer performance of hybrid surface compares with smooth surface and hydrophobic surface, and the process of hybrid surface steam condensation is visualized using a high-speed camera. It is found that superhydrophilic-hydrophobic hybrid surface can better regulate the condensate droplet size, and its condensation heat transfer performance is better than that of smooth surface and hydrophobic surface. At △T=4.3 K, the heat transfer coefficient of the 2.5 mm grid spacing hybrid surface is 2.2 times and 1.6 times of the smooth surface and hydrophobic surface respectively. In the three superhydrophilic grid line spacings hybrid surface, the heat transfer performance of 2.5 mm grid spacing hybrid surface is overall best, and at △T=9.0 K, the heat transfer coefficient of the 2.5 mm grid spacing hybrid surface is 1.2 times and 1.8 times of 1.5 mm grid spacing hybrid surface and 3.5 mm grid spacing hybrid surface, respectively.

Key words: condensation heat transfer, hybrid surface, hydrophobic, superhydrophilic

CLC Number:

TG156

ZHOU Dongdong, JI Xianbing, DAI Chao, XU Jinliang. Steam Condensation Heat Transfer Enhancement on Superhydrophilic-Hydrophobic Hybrid Vertical Surface[J]. Journal of Mechanical Engineering, 2018, 54(10): 182-187.

References

[1] PAREKH S, FARIDB M M, SELMANA J R, et al. Solar desalination with a humidification-dehumidification technique-a comprehensive technical review[J]. Desalination, 2004, 160:167-186.
[2] 徐敬华, 张树有, 谭建荣. 大型空分板翅换热器性能强化的逐流段设计方法[J]. 机械工程学报, 2015, 51(9):129-136. XU Jinghua, ZHANG Shuyou, TAN Jianrong. Segmented design of performance enhancement for large Plate fin heat exchanger of cryogenic air separation unit[J]. Journal of Mechanical Engineering, 2015, 51(9):129-136.
[3] WATANABE N, ARITOMI M, MACHIDA A. Time- series characteristics and geometric structures of drop-size distribution density in dropwise condensation[J]. International Journal of Heat and Mass Transfer, 2014, 76:467-483.
[4] 马志先, 张吉礼, 孙德兴. 管束效应对HFC245fa与HCFC123膜状凝结换热影响[J]. 机械工程学报, 2012, 48(4):129-135, 145. MA Zhixian, ZHANG Jili, SUN Dexing. Effect of inundation on film condensation of HFC245fa and HCFC123 on horizontal tubes[J]. Journal of Mechanical Engineering, 2012, 48(4):129-135, 145.
[5] 胡灿, 李敏霞, 马一太, 等. 小通道内的冷凝换热模型分析[J]. 机械工程学报, 2012, 48(24):134-140. HU Can, LI Minxia, MA Yitai, et al. Analysis of condensation heat transfer model in small channels[J]. Journal of Mechanical Engineering, 2012, 48(24):134-140.
[6] WANG Buxuan, REN Zepei, HUANG Qili, et al. Experimental study of condensation heat transfer for colling gas flow containing water vapor[J]. Chinese Journal of Mechanical Engineering, 1988, 1(1):13-22.
[7] 宋永吉, 任晓光, 任绍梅, 等. 水蒸气在超疏水表面上的冷凝传热[J]. 工程热物理学报, 2007, 28(1):95-97. SONG Yongji, REN Xiaoguang, REN Shaomei, et al. Condensation heat transfer of steam on super-hydrophobic surfaces[J]. Journal of Engineering Thermophysics, 2007, 28(1):95-97.
[8] 马学虎, 李洪安, 徐敦颀, 等. 超薄聚合物表面上滴状冷凝的传热研究[J]. 高校化学工程学报, 1993, 7(4):309-315. MA Xuehu, LI Hongan, XU Dunxin, et al. A study of dropwise condensation heat transfer on the superthin polymer surface[J]. Journal of Chemical Engineering of Chinese Universities,1993, 7(4):309-315.
[9] KIM H, NAM Y. Condensation behaviors and resulting heat transfer performance of nano-engineered copper surfaces[J]. International Journal of Heat and Mass Transfer, 2016, 93:286-292.
[10] CHU Fuqiang, WU Xiaomin. Fabrication and condensation characteristics of metallic superhydrophobic surface with hierarchical micro-nano structures[J]. Applied Surface Science, 2016, 371:322-328.
[11] VARANASI K K, DENG T. Controlling Nucleation and Growth of Water Using Hybrid Hydrophobic-Hydrophilic Surfaces[C]//14th International Heat Transfer Conference, Washington DC, ASME, 2010:447-452.
[12] DERBY M M, CHATTERJEE A, PELES Y, et al. Flow condensation heat transfer enhancement in a mini-channel with hydrophobic and hydrophilic patterns[J]. International Journal of Heat and Mass Transfer, 2014, 68:151-160.
[13] HU H W, TANG G H, NIU D. Experimental investigation of condensation heat transfer on hybrid wettability finned tube with large amount of noncondensable gas[J]. International Journal of Heat and Mass Transfer, 2015, 85:513-523.
[14] 彭本利, 马学虎, 兰忠, 等. 组合表面调控液滴特性强化蒸汽冷凝传热[J]. 化工学报, 2015, 6(10):3826-3833. PENG Benli, MA Xuehu, LAN Zhong, et al. Steam condensation heat transfer enhancement through droplet properties manipulation with hybrid surfaces[J]. CIESC Journal, 2015, 6(10):3826-3833.
[15] MAHAPATR P S, GHOSH A, GANGULY R, et al. Key design and operating parameters for enhancing dropwise condensation through wettability patterning[J]. International Journal of Heat and Mass Transfer, 2016, 92:877-883.
[16] BERMAN L D. Effect of vapor velocity on heat transfer during condensation[J]. Journal of Applied Mechanics and Technical Physics, 1971, 12(6):946-948.
[17] SIGSBEE R A, POUND G M. Heterogeneous nucleation from the vapor[J]. Advances In Colloid And Interface Science, 1967, 1(3):335-390.
[18] KIM S, KIM K J. Dropwise condensation modeling suitable for superhydrophobic surface[J]. Journal of Heat Transfer, 2011, 133(8):081502-081502-8.