蓄冷冰球中相变传热过程的数值分析  

Numerical simulation of phase change heat transfer in cold storage sphere

作　　者：张奕[1] 胡洪[1] 翁雯[1] 刘佳[1] 祝用华[1] 

机构地区：[1]南京师范大学动力工程学院,江苏南京210042

出　　处：《江苏大学学报（自然科学版）》2009年第1期49-52,共4页Journal of Jiangsu University：Natural Science Edition

基　　金：江苏省普通高校自然科学研究计划项目(06KJD480097)

摘　　要：对蓄冷冰球中的相变传热进行分析,建立传热的数值方程.试验测量冰球中心的温度曲线,该曲线计算和试验结果的对比表明,文中的数值方法可以对冰球中的相变传热过程进行准确计算.计算结果亦反映出,直径100 mm冰球完全相变所需时间约为50 mm冰球的2.4倍.球壳和传热流体的对流传热系数较小时,增加对流传热系数对提高相变速率有显著影响.冰球相变所需时间和相变材料的初温呈线性关系,传热流体温度接近相变温度时,传热流体温度变化对相变时间有显著影响.计算结果可用于指导蓄冷冰球的传热参数设计.Heat transfer equations describing the phase change in a cold storage sphere were set up. The control volume method was used to construct finite differential equations. Temperature curves in an ice sphere during phase change processes were measured by experiments. The numerical results of these temperature curves agree well with experimental ones. It is found that phase change time for a sphere of 100 mm diameter is 2.4 times of that needed for a sphere of 50 mm diameter. When the convective heat transfer coefficient is at a low value, increase of the coefficient can decrease the phase change time remarkably. Phase change time increases linearly with the initial temperature of ice sphere. When the temperature of heat transfer fluid is near 0 ℃, change of temperature influences phase change time sharply. The calculated results can be used to determine the heat transfer parameters of ice spheres for thermal storage usage.

关 键 词：蓄冷 凝固 熔化 相变传热 数值计算 

分 类 号：TK124[动力工程及工程热物理—工程热物理]