金属泡沫中填充石蜡的相变换热特性试验研究.pdfVIP

金属泡沫中填充石蜡的相变换热特性实验研究 张嘉杰，屈治国* (热流科学与工程教育部重点实验室，西安交通大学能源与动力工程学院，陕西 西安 710049) 摘 要 ：本文对金属铜泡沫填充石蜡的相变换热特征进行了实验研究，通过测试试件加热面及内部的温度响应曲线，分析了 属泡沫填充及自然对流对石蜡非稳态相变换热过程的影响。研究结果表明，采用顶部加热方式时，石蜡内部的换热以纯导热为 主，而采用底部加热时，液态石蜡内的自然对流作用使相界面移动速度更快，试件内部温度一致性更好，同时在相变对流区可 实现对加热面的温度控制。金属泡沫的填充可强化石蜡内的导热但抑制液态石蜡的自然对流，前者使得试件加热面温升减缓， 相界面移动加快，后者则导致底部加热时石蜡的相变区分为相变导热区和相变对流区。金属泡沫的导热强化能力在试件换热中 占据主导作用。 关键词：石蜡；金属泡沫；相变区；自然对流 中图分类号：TK124 文献标识码：A Experimental study on the heat transfer of metal foam filled in paraffin 1 * v ZHANG Jia-Jie QU Zhi-Guo 3 (MOE Key Laboratory of Thermal Fluid Science and Engineering, School of Energy and Power Engineering, Xian Jiaotong University, 1 0 Xian, Shaanxi 710049) 0 Abstract: In this study, the thermal performance of paraffin saturated open cell metal foam was experimentally investigated by tracking 0 the heated surface and internal temperatures. The effects of metal foam and natural convection on heat transfer in paraffin were . 0 discussed. The results showed that the heat conduction played a dominant role for the case of top heating. For the case of bottom heating, 1 7 the natural convection in liquid paraffin led to the quicker phase change interface movement and more uniform internal temperature. 1 Meanwhile, the tem