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| Experimental study of heat and mass transfer of saltwater cooling tower |
| WANG Chao, DONG Fei-ying, FAN Li-wu, YU Zi-tao, HU Ya-cai |
| Institute of Thermal Science and Power Systems, Zhejiang University, Hangzhou 310027, China |
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Abstract Experiments were performed on a mechanical-draft counter-flow cooling tower to analyze the heat and mass transfer of saltwater cooling towers at high concentrations. By maintaining the inlet saltwater temperature at 28～50 ℃,the effects of mass fraction of the saltwater (6%, 12%, 16%, 25%, and 34% aqueous CaCl2 solutions) and Reynolds number Re (ranging between 2 000～16 000) on the non-dimensional heat and mass transfer coefficients, NuV and ShV were respectively analyzed. Results show that self-scaling phenomenon is occurred in packing layer of saltwater cooling tower, and the NuV Pr-1/3 and ShV Sc-1/3 are nearly independent of Re. The heat and mass transfer performance of the cooling towers deteriorates with increasing the concentration of the saltwater. When the mass fraction is increased from 6% to 34%, NuVPr-1/3 and ShVSc-1/3 are decreased by 51.5% and 45.8%, respectively. Correlations of NuVPr-1/3 and ShVSc-1/3 to the variation of concentration were proposed based on linear curve fitting.
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Published: 03 September 2014
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盐水冷却塔传热传质特性的实验研究
为了研究高浓度盐水冷却塔的传热传质特性,通过机械通风式逆流冷却塔实验台,在不同进塔盐水温度（28～50 ℃）的条件下,研究改变盐水质量分数(6%、12%、16%、25%和34%的氯化钙溶液）及雷诺数Re（范围：2 000～16 000）分别对无量纲换热系数NuV和无量纲传质系数ShV的影响.结果表明：NuVPr-1/3和ShVSc-1/3均与Re无关,即在填料层内发生了关于Re的自模化现象；随着盐水质量分数的升高,盐水冷却塔的传热和传质性能均有所下降.当盐水质量分数由6%提高到34%时,NuVPr-1/3的平均值下降了51.5%,ShVSc-1/3的平均值下降了45.8%.通过线性拟合得到了NuVPr-1/3和ShVSc-1/3随盐水质量分数变化的关联式.
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