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【摘要】 分析了纳米流体强化传热的机理,提出了在除湿溶液中添加纳米铜粒子以提高其传热性能的可行性,并实验测试了在加热和冷却条件下,氯化锂溶液添加纳米铜粒子前后的(传)导热性能变化以及常温下纳米铜粒子的体积分数的影响。实验结果表明:无论加热还是冷却过程,纳米溶液的传热性能都明显高于纯氯化锂溶液,纳米铜粒子的高导热系数,促进了溶液内部热量传递;纳米氯化锂溶液的导热系数随着铜粒子在溶液中质量分数的增加而增大,体积分数小于0.03时,实验结果符合Maxwell模型计算值;大于0.03,铜粒子含量越高,两者偏差越大;纳米铜粒子对于液体传热性能的影响因基液的不同而差别较大。 【Abstract】 The heat transfer enhancement mechanism of nano-fluid was analyzed and the feasibility was discussed for adding nano-copper particles to the desiccant solution to enhance heat transfer performance.Experiments were conducted to test thermal conductivity variations of the nano-lithium chloride solution under heating and cooling conditions.The influence of the volume fraction of nano-copper particles on the thermal conductivity was also investigated.The experimental results show that nano-copper particles could enhance the thermal conductivity of the nano-lithium chloride solution significantly.The conductivity of the nano-lithium chloride solution increased with the increase in the volume fraction of nano-copper particles.When the volume fraction was less than 0.03,the experimental results agreed with the values obtained by the Maxwell model while the difference between them increased with the increase in copper particles in the solution when the volume fraction was greater than 0.03. 【关键词】 工程热物理; 液体除湿; 强化传热; 纳米流体; 氯化锂溶液; 导热系数 【Key words】 Engineering thermophysics; Liquid desiccant; Heat Transfer Enhancement; Nanofluids; Lithium chloride solution; Thermal conductivity