纳米流体在圆管型丝网热管换热强化中的应用
Application of nanofluid in thermal performance enhancement of horizontal screen heat pipe
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摘要: 对纳米流体强化水平放置的丝网热管换热特性进行了实验研究.实验工质为水基CuO纳米流体,颗粒平均粒径50 nm,质量分数为0.5%~2.0%.实验在定压下进行,压力为7.45~19.97 kPa.结果显示,纳米流体替代去离子水后,热管换热性能大幅度提高.蒸发段换热系数提高了170%~410%.运行压力对热管换热特性有明显影响.压力越小,热管换热的强化越显著.热管换热特性随纳米流体质量分数的增加而提高,到达一定值后开始随之下降,最佳质量分数在1.0%左右.Abstract: The heat transfer characteristic of horizontal screen heat pipe using nanofluid was studied experimentally.The nanofluid consists of water and CuO nanoparticles having a mean diameter of 50 nm,the mass concentration of nanofluid ranges from 0.5% to 2.0%,and the operational pressures of the heat pipe varies from 7.45 kPa to 19.97 kPa.The experimental results show that the effect of the particle concentration on both evaporating and condensing heat transfer coefficients and the maximum heat flux is very significant.At the pressure of 19.97 kPa,the evaporating heat transfer coefficient rises from 170% to 410%.The operational pressure yields very significant effect on the heat transfer enhancement for the heat pipe.The lower operational pressure indicates more significant thermal performance enhancement of the heat pipe.The heat transfer characteristic improves with the rise of mass concentration,and then drops after reaching a certain value,while the optimal mass concentration is 1%.
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Key words:
- nanofluid /
- heat pipe /
- heat transfer enhancement /
- screen
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[1] Choi S U S.Enhancing thermal conductivity of fluids with nanoparticIes[J].ASME FED,1995,231:99-105. [2] Murshed S M S,Leong K C,Yang C.Enhanced thermal conductivity of Tio2-water based nanofluids[J].Int.J.Thermal Sciences,2005,44:367-373. [3] 李强,宣益民.纳米流体热导率的测量[J].化工学报,2003.54(1).42-46.LI Qiang,XUAN YiMin.Measurements of themaI conductivity of nanofluid[J].Journey of Chemical Industry and Engineering,2003,54(1):42-46.(in Chinese) [4] 李强,宣益民.铜-水纳米流体与对流换热特性[J].中国科学:E辑,2002,32(3):331-337.LI Qiang,XUAN Yimin.The convection character of heat transfer and flow of Cu-Water nanofluid[J].Science in China(Series E),2002,32(3):331-337.(in Chinese) [5] Das S K,Putra N,Roetzel W.Pool boiling characteristics of nanofluids[J].Int.J.Heat Mass Transfer,2003,46:851-862. [6] Bang I C,Chang S H.Boiling heat transfer performance and phenomena of A120s-water nanofluids from a plain surface in a pool[J].Int.J.Heat Mass Transfer,2005,48:2407-2419. [7] WEN Dongsheng,DING Yulong.Experimental investigation to the pool boiling heat transfer of aqueous based alumina nanofluids[J].Journal of Nanoparticles Research.2005,7:265-275. [8] Tsai C Y,Yang H Y.Effect of nanofluid concentration On heat pipe thermal performance[J].ASME Transactions,2005,2:1432-1439. [9] Tsai C Y,Chien H T,Ding P P.Effect of structural character of gold nano-particles in nanofluid on heat pipe thermal performance[J].Materials Letters,2004,58:1461-1465. [10] XUE Huaisheng,FAN Jianren.The interface effect of carbon nanotube suspension on the thermal performance of a two-phase closed thermosyphon[J].Journal of Applied Physics,2006,100:1-6. [11] LIU Zhenhua,LIAO Liang.Sorption and agglutination phenomenon of nanofluids on a plain heated surface during pool boiling[J].J.Shanghai Jiaotong University.2007,41(3):352-356.
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