相变太阳能集热管放热特性的数值研究

NUMERICAL STUDY ON THE HEAT RELEASE CHARACTERISTIC OF SOLAR THERMAL COLLECTOR WITH PHASE CHANGE MATERIAL

采用计算流体力学(CFD)的方法分析了单根太阳能集热管的放热过程,讨论了热水管管材分别为316L不锈钢、黄铜、紫铜三种情况。结果表明,随着热水管导热系数的增大,单根太阳能集热管的放热速率没有明显提高。相变放热过程的主要传热热阻不是热水管的导热热阻,而是由固态相变材料(PCM)的导热系数低所致。

Computational Fluid Dynamics（CFD） method was used to analyze the heat release process of solar thermal collector with three different kinds of materials for hot water pipes, namely 316 L stainless steel, brass and copper. The results show that the heat release performance is not obviously improved when the thermal conductivity of hot water pipe is increased. Further discussion reveals that the main heat transfer resistance is caused by the low thermal conductivity of PCM in the solid state instead of the thermal resistance of hot water pipe.