Effect of surface wettability on heat transfer performance of oscillating heat pipe

doi:10.11949/j.issn.0438-1157.20170665

Abstract

Abstract:

Experiments were performed to understand the influence of surface wettability on heat transfer performance of an oscillating heat pipe (OHP),the alkali assistant surface oxidation technique was used to fabricate the surfaces. The surfaces with different wettability were obtained by control the concentration of the reaction solution of sodium hydroxide and ammonium persulfate. Different OHPs were obtained with the surface contact angles(CA) of 0°、33.9°、55.7°、84.3°,respectively. The effect of different degrees of surface wettability on heat transfer performance of oscillating heat pipe was investigated experimentally. The results show that the oscillating frequency and amplitude of the working fluid in the OHP increases as the CA increases. The thermal resistance and temperature difference of OHP decreases as the CA increases. Therefore,heat transfer performance of the OHP was enhanced as the CA increases.

Key words: oscillating heat pipe, heat transfer, interfacial tension, wettability degree, gas-liquid flow

摘要：

为了深入理解表面浸润性对脉动热管传热性能的影响，利用碱性辅助表面氧化技术，通过控制氢氧化钠和过硫酸铵溶液与铜表面反应浓度的变化，制备了具有不同浸润程度表面的脉动热管，其表面接触角分别为0°、33.9°、55.7°、84.3°。通过实验研究了表面浸润程度对脉动热管传热性能的影响。结果显示，随着脉动热管内部浸润性的增强，其脉动频率及幅度增加，脉动热管热阻及温差降低，传热性能得到强化。

关键词: 脉动热管, 传热, 界面张力, 浸润程度, 气液两相流

CLC Number:

TK124

JI Yulong, YU Chunrong, ZHANG Qingzhen, SUN Da. Effect of surface wettability on heat transfer performance of oscillating heat pipe[J]. CIESC Journal, 2017, 68(S1): 141-149.

纪玉龙, 庾春荣, 张庆振, 孙达. 表面浸润程度对脉动热管传热性能的影响[J]. 化工学报, 2017, 68(S1): 141-149.

References 30

[1]	AKACHI H. Structure of a hear pipe:US4921041[P]. 1990-05-01.
[2]	杨蔚原,张正芳,马同泽. 回路型脉动热管的运行与传热[J]. 上海交通大学学报,2003,37(9):1398-1401. YANG W Y,ZHANG Z F,MA T Z. Operation and heat transfer of the pulsating heat pipe of the loop type[J]. Journal of Shanghai Jiao Tong University,2003,37(9):1398-1401.
[3]	曲伟,马同泽. 脉动热管的工质流动和传热特性实验研究[J]. 工程热物理学报,2002,23(5):596-598. QU W,MA T Z. Experimental study on fluid flow and heat transfer characteristics of pulsating heat pipe[J]. Journal of Engineering Thermophysics,2002,23(5):596-598.
[4]	张显明,徐进良,施慧烈. 倾斜角度及加热方式对脉冲热管传热性能的影响[J]. 中国电机工程学报,2004,24(11):222-227. ZHANG X M,XU J L,SHI H L. Effect of tilt angle and heating mode on heat transfer performance of pulsating heat pipe[J]. Proceeding of the CSEE,2004,24(11):222-227.
[5]	王伟. 脉动热管的传热性能和启动特性[D]. 长沙:中南大学,2007. WANG W. Heat transfer performance and starting characteristics of an pulsating heat pipe[D]. Changsha:Central South University,2007.
[6]	LIU T Y,LIP L,LIU C W,et al. Boiling flow characteristics in microchannels with very hydrophobic surface to super-hydrophilic surface[J]. International Journal of Heat and Mass Transfer,2011,54(1):126-134.
[7]	PHAN H T,CANEY N,MARTY P,et al. Surface wettability control by nanocoating:the effects on pool boiling heat transfer and nucleation mechanism[J]. International Journal of Heat and Mass Transfer,2009,52(23):5459-5471.
[8]	CHOI C,SHIN J S,YU D I, et al. Flow boiling behaviors in hydrophilic and hydrophobic microchannels[J]. Experimental Thermal and Fluid Science,2011,35(5):816-824.
[9]	郑晓欢,纪献兵,王野,等. 超亲/疏水性表面池沸腾传热研究[J]. 化工进展,2016,35(12):3793-3798. ZHENG X H,JI X B,WANG Y, et al. Study on boiling heat transfer of super-hydrophilic/hydrophobic surface[J]. Progress in Chemical Industry,2016,35(12):3793-3798.
[10]	PHAN H T,CANEY N,MARTY P,et al. How does surface wettability influence nucleate boiling?[J]. Comptes Rendus Mécanique,2009,337(5):251-259.
[11]	KANDLIKAR S G. A theoretical model to predict pool boiling CHF incorporating effects of contact angle and orientation[J]. Transactions-American Society of Mechanical Engineers Journal of Heat Transfer,2001,123(6):1071-1079.
[12]	CHU K H,SOO J Y,ENRIGHT R,et al. Hierarchically structured surfaces for boiling critical heat flux enhancement[J]. Applied Physics Letters,2013,102(15):151602.
[13]	AHN H S,JO H J,KANG S H,et al. Effect of liquid spreading due to nano/microstructures on the critical heat flux during pool boiling[J]. Applied Physics Letters,2011,98(7):071908.
[14]	CHEN R,LU M C,SRINIVASAN V,et al. Nanowires for enhanced boiling heat transfer[J]. Nano Letters,2009,9(2):548-553.
[15]	QU W,MA H B. Theoretical analysis of startup of a pulsating heat pipe[J]. International Journal of Heat and Mass Transfer,2007,50(11):2309-2316.
[16]	JI Y,XU C,MA H,et al. An experimental investigation of the heat transfer performance of an oscillating heat pipe with copper oxide (CuO) microstructure layer on the inner surface[J]. Journal of Heat Transfer,2013,135(7):074504.
[17]	DOBSON R T,SWANEPOEL G. An experimental investigation of the thickness of the liquid-film deposited at the trailing end of a liquid plug moving in the capillary tube of a pulsating heat pipe[J]. Frontiers in Heat Pipes (FHP),2010,http://dx.doi.org/10.5098/fhp.v1.1.3004.
[18]	HAO T,MA X,LAN Z, et al. Effects of hydrophilic surface on heat transfer performance and oscillating motion for an oscillating heat pipe[J]. International Journal of Heat and Mass Transfer,2014,72:50-65.
[19]	郝婷婷,马学虎,兰忠,等. 超亲水脉动热管液弹液膜沉积的实验研究[J]. 工程热物理学报,2015,36(1):168-171. HAO T T,MA X H,LAN Z,et al. Experimental investigation of the effect of superhydrophilic surface on the liquid film deposition of a pulsating heat pipe[J]. Journal of Engineering Thermophysics,2015,36(1):168-171.
[20]	JI Y,CHEN H,KIM Y J,et al. Hydrophobic surface effect on heat transfer performance in an oscillating heat pipe[J]. Journal of Heat Transfer,2012,134(7):074502.
[21]	HAO T T,MA X H,ZHONG L,et al. Effects of hydrophobic surface on heat transfer performance and oscillating motion for a pulsating heat pipe[J]. International Journal of Heat and Mass Transfer,2014,72(1):50-65.
[22]	ZHU X,WANG H,LIAO Q,et al. Experiments and analysis on self-motion behaviors of liquid droplets on gradient surfaces[J]. Experimental Thermal and Fluid Science,2009,33(6):947-954.
[23]	CHANDESRIS B,SOUPREMANIEN U,DUNOYER N. Uphill motion of droplets on tilted and vertical grooved substrates induced by a wettability gradient[J]. Colloids and Surfaces A:Physicochemical and Engineering Aspects,2013,434:126-135.
[24]	LAIBINIS P E,WHITESIDES G M. Self-assembled monolayers of n-alkanethiolates on copper are barrier films that protect the metal against oxidation by air[J]. Journal of the American Chemical Society,1992,114(23):9022-9028.
[25]	YU X,WANG Z,JIANG Y,et al. Surface gradient material:from superhydrophobicity to superhydrophilicity[J]. Langmuir,2006,22(10):4483-4486.
[26]	ITO Y,HEYDARI M,HASHIMOTO A,et al. The movement of a water droplet on a gradient surface prepared by photodegradation[J]. Langmuir,2007,23(4):1845-1850.
[27]	SUN C,ZHAO X W,HAN Y H,et al. Control of water droplet motion by alteration of roughness gradient on silicon wafer by laser surface treatment[J]. Thin Solid Films,2008,516(12):4059-4063.
[28]	WANG L,PENG B,SU Z. Tunable wettability and rewritable wettability gradient from superhydrophilicity to superhydrophobicity[J]. Langmuir,2010,26(14):12203-12208.
[29]	LI X,DAI H,TAN S,et al. Facile preparation of poly (ethyl α-cyanoacrylate) superhydrophobic and gradient wetting surfaces[J]. Journal of Colloid and Interface Science,2009,340(1):93-97.
[30]	HUANG Z,ZHANG J,CHENG J,et al. Preparation and characterization of gradient wettability surface depending on controlling Cu(OH)2 nanoribbon arrays growth on copper substrate[J]. Applied Surface Science,2012,259:142-146.