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科学通报  2015 

低压蒸汽滴状冷凝中液滴脱落滞后效应

DOI: 10.1360/N972014-01326, PP. 2784-2789

Keywords: 滴状冷凝,低压蒸汽,液滴脱落,动态特性,滞后效应

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Abstract:

利用界面结构效应实现蒸汽滴状冷凝对能源动力系统的高效化和集成化具有至关重要的作用.深入认识液滴动态特性对传热性能的影响有利于探究低压蒸汽冷凝中传热控制机理和研发高效紧凑的传热强化技术.本文系统地研究了蒸汽滴状冷凝中液滴脱落特性,提出了低压蒸汽冷凝液滴脱落滞后效应.随着蒸汽压力降低,冷凝液滴黏度增加,引起自身脉动特性下降,接触线移动受阻,接触角滞后现象明显,导致脱落尺寸明显增加而脱落速度大大降低.与常压蒸汽冷凝中液滴的快速启动连续下落不同,低压蒸汽冷凝中液滴长至脱落尺寸后表现出了“阶跃式”下落的现象,即液滴脱落滞后效应.在液滴整个生命周期中,低过冷度时液滴生长速度控制着传热过程,而高过冷度时液滴脱落滞后延缓了表面更新,降低了有效换热面积,成为了控制传热过程的因素.通过液滴脱落效应解释了传热通量随过冷度非线性增加现象的内在机理,明晰了蒸汽冷凝传热控制机制,为低压蒸汽冷凝传热强化指明了方向.

References

[1]  27 Chen X M, Wu J, Ma R Y, et al. Nanograssed micropyramidal architectures for continuous dropwise condensation. Adv Funct Mater, 2011, 21: 4617-4623
[2]  1 Ma X H, Chen J B, Li S P, et al. Application of absorption heat transformer to recover waste heat from a synthetic rubber plant. Appl Therm Eng, 2003, 23: 797-806
[3]  2 Khawaji A D, Kutubkhanah I K, Wie J M. Advances in sea-water desalination technologies. Desalination, 2008, 221: 47-69
[4]  3 Andrews H G, Eccles E A, Schofield W C E, et al. Three-dimensional hierarchical structures for fog harvesting. Langmuir, 2011, 27: 3798-3802
[5]  4 Milani D, Abbas A, Vassallo A, et al. Evaluation of using thermoelectric coolers in a dehumidification system to generate freshwater from ambient air. Chem Eng Sci, 2011, 66: 2491-2501
[6]  5 Miljkovic N, Enright R, Wang E N. Effect of droplet morphology on growth dynamics and heat transfer during condensation on superhydrophobic nanostructured surfaces. ACS Nano, 2011, 5: 5962-5968
[7]  6 Lan Z, Ma X H, Wang S F, et al. Effects of surface free energy and nanostructures on dropwise condensation. Chem Eng J, 2010, 156: 546-552
[8]  7 Enright R, Miljkovic N, Dou N, et al. Condensation on superhydrophobic copper oxide nanostructures. J Heat Transfer, 2013, 135: 091304
[9]  8 Rausch M H, Fr?ba A P, Leipertz A. Dropwise condensation heat transfer on ion-implanted aluminum surfaces. Int J Heat Mass Transfer, 2008, 51: 1061-1070
[10]  9 Rausch M H, Leipertz A, Fr?ba A P. Dropwise condensation heat transfer on ion-implanted titanium surfaces. Int J Heat Mass Transfer, 2010, 53: 423-430
[11]  10 Volchkov E P, Makarov M S, Makarova S N. Heat and mass diffusion fluxes on a permeable wall with foreign-gas blowing. Int J Heat Mass Transfer, 2012, 55: 1881-1887
[12]  11 Ma X H, Zhou X D, Lan Z, et al. Condensation heat transfer enhancement in the presence of non-condensable gas using the interfacial effect of dropwise condensation. Int J Heat Mass Transfer, 2008, 51: 1728-1737
[13]  12 Wen R F, Lan Z, Peng B L, et al. Droplet dynamics and heat transfer for dropwise condensation at lower and ultra-lower pressure. Appl Therm Eng, 2014, doi: 10.1016/j.applthermaleng.2014.09.069
[14]  13 Tanaka H. Effect of Kundsen number on dropwise condensation. J Heat Transfer, 1981, 103: 606-607
[15]  14 Vemuri S, Kim K J, Wood B D, et al. Long term testing for dropwise condensation using self-assembled monolayer coating of n-octadecyl mercaptan. Appl Therm Eng, 2006, 26: 421-429
[16]  15 Vemuri S, Kim K J. An experimental and theoretical study on the concept of dropwise condensation. Int J Heat Mass Transfer, 2006, 49: 649-657
[17]  16 Wilmshurst R, Rose J W. Dropwise condensation-further heat transfer measurement. In: Proceeding of 4th International Heat Transfer Conference. Versailles, 1970. 6: 1-4
[18]  17 Graham C. The limiting heat transfer mechanisms of dropwise condensation. Dissertation for Doctoral Degree. Cambridge: Massachusetts Institute of Technology, 1969
[19]  18 Tanaka H, Tsuruta T A. A microscopic study of dropwise condensation. Int J Heat Mass Transfer, 1984, 27: 327-335
[20]  19 Hatamiya S, Tanaka H. Dropwise condensation of steam at low pressures. Int J Heat Mass Transfer, 1987, 30: 497-507
[21]  20 Ma X H, Wang S F, Lan Z, et al. Wetting mode evolution of steam dropwise condensation on superhydrophobic surface in the presence of noncondensable gas. J Heat Transfer, 2012, 134: 021501
[22]  21 Miljkovic N, Enright R, Nam Y, et al. Jumping-droplet-enhanced condensation on scalable superhydrophobic nanostructured surfaces. Nano Lett, 2013, 13: 179-187
[23]  22 Rykaczewski K, Scott J H J. Methodology for imaging nano-to-microscale water condensation dynamics on complex nanostructures. ACS Nano, 2011, 5: 5962-5968
[24]  23 Rykacaewski K, Chinn J, Walker M L, et al. Dynamics of nanoparticle self-assembly into superhydrophobic liquid marbles during water condensation. ACS Nano, 2011, 5: 9746-9754
[25]  24 Dietz C, Rykaczewski K, Fedorv A G, et al. Visualization of droplet departure on a superhydrophobic surface and implications to heat transfer enhancement during dropwise condensation. Appl Phys Lett, 2010, 97: 033104
[26]  25 Anand S, Son S Y. Sub-micrometer dropwise condensation under superheated and rarefied vapor condition. Langmuir, 2010, 26: 17100-17110
[27]  26 Boreyko J B, Chen C H. Self-propelled dropwise condensate on superhydrophobic surfaces. Phys Rev Lett, 2009, 103: 184501
[28]  28 Yamali C, Merte H J. A theory of dropwise condensation at large subcooling including the effect of the sweeping. Heat Mass Transfer, 2002, 38: 191-202
[29]  29 Lan Z, Ma X H, Wang S F, et al. Effect of surface free energy and nanostructures on dropwise condensation. Chem Eng J, 2010, 156: 546-552
[30]  30 Wilcox S J, Rohsenow W M. Film condensation of potassium using copper condensing block for precise wall-temperature measurement. J Heat Transfer, 1970, 92: 359-371
[31]  31 Liao Q, Zhu X, Xing S M. Visualization study on coalescence between pair of water drops on inclined surfaces. Exp Therm Fluid Sci, 2008, 32: 1647-1654
[32]  32 Manor O. Diminution of contact angle hysteresis under the influence of an oscillating force. Langmuir, 2014, 30: 6814-6845
[33]  33 Dimitrakopoulos P, Higdon J J L. On the gravitational displacement of three-dimensional fluid droplets from inclined solid sufaces. J Fluid Mech, 1999, 395: 181-209
[34]  34 Kim H Y, Lee H J, Kang B H. Sliding of liquid drops down an inclined solid surface. J Colloid Interface Sci, 2002, 247: 372-380
[35]  35 Chatterjee A, Derby M M, Peles Y, et al. Condensation heat transfer on patterned surfaces. Int J Heat Mass Transfer, 2013, 66: 889-897
[36]  36 Qi B J, Zhang L, Xu H. Experiment study on condensation heat transfer of steam on vertical titanium plates with different surface energies. Exp Therm Fluid Sci, 2011, 35: 211-218

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