圆柱形相变储热器热损失的研究

Analysis of heat loss on cylindrical phase change thermal storage

相变储热具有密度高、体积小、质量轻、蓄放热过程中温度波动小等优点,在太阳能热利用、工业余热回收、采暖及空调等领域有着较为广泛的应用。文章建立了相变储热器的三维模型,搭建相变储热实验平台对模型的准确性进行了验证;使用Fluent软件对相变储热器稳态条件的热损失进行了分析,得到热损失系数K与熔盐温度的关系为K=0.000 28t+0.162;对储热器非稳态散热进行了模拟,分析了储热器散热过程,得到了熔盐凝固速度和外部壁面热损失随时间变化的规律。

Phase change heat storage has the advantages of high density, small size, light weight and small temperature fluctuation during storage exothermic process, and it has wide application in solar heat, industrial waste heat recovery, heating, air-conditioning and other fields. In this paper, a threedimensional model of the phase change thermal storage is established, and a phase change thermal storage experiment platform is built to validate the accuracy of the model. The heat loss under the steady-state condition is analyzed by using Fluent software, and the relationship between heat loss co- efficient K and the temperature of the molten salt is gotten as follows. K=-0. 000 28t＋0. 162. The simulation of the unsteady heat of thermal storage is carried out, the heat dissipation process is analyzed, and the variation law of salt solidification rate and external wall heat loss with time is gotten.