本文研究了三种强化管对降膜蒸发换热效果的影响,利用热阻分析的方法,求得不同工况下降膜蒸发的换热系数.以水为介质,实验在绝对压力为1000 Pa的条件下进行.通过对换热系数与降膜流量之间关系的研究,发现随着流量的增大,降膜蒸发过程分成管壁部分干涸以及全湿润两个状态;当流量处于转变值时,降膜蒸发的换热系数达到最大值.另外结果表明,当降膜雷诺数在10~110范围内,Turbo-CAB(26fpi)管表面的降膜蒸发换热系数是光管的3~5倍;但当液膜完全覆盖Turbo-CAB的翅片时,其强化换热效果将变差.
参考文献
[1] | Gherhardt Ribatski;Anthony M. Jacobi .Falling-film evaporation on horizontal tubes-a critical review[J].International Journal of Refrigeration,2005(5):635-653. |
[2] | Zhen-Hua Liu;Jie Yi .Falling film evaporation heat transfer of water/salt mixtures from roll-worked enhanced tubes and tube bundle[J].Applied thermal engineering: Design, processes, equipment, economics,2002(1):83-95. |
[3] | Alhusseini AA.;Chen JC.;Tuzla K. .Falling film evaporation of single component liquids[J].International Journal of Heat and Mass Transfer,1998(12):1623-1632. |
[4] | Luopeng Yang;Shengqiang Shen .Experimental study of falling film evaporation heat transfer outside horizontal tubes[J].Desalination: The International Journal on the Science and Technology of Desalting and Water Purification,2008(1/3):654-660. |
[5] | 许莉,王世昌,王宇新,凌毅.水平管薄膜蒸发传热系数[J].化工学报,2003(03):299-304. |
[6] | Ribatski G;Thome JR .Experimental study on the onset of local dryout in an evaporating falling film on horizontal plain tubes[J].Experimental Thermal and Fluid Science: International Journal of Experimental Heat Transfer, Thermodynamics, and Fluid Mechanics,2007(6):483-493. |
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