铝/石蜡复合相变材料蓄热性能的数值模拟

相变储能材料由于其具有周期性储存和释放能量的特点，在电池热管理、太阳能发电等领域存在着广泛的应用。然而由于导热系数低的原因限制了其进一步的应用。高导热率泡沫材料的添加为解决这一不足提供了一种有效的方法。文章采用三周期性极小曲面（TPMS）生成泡沫铝骨架，基于孔隙尺度数值模拟了铝/石蜡复合相变材料相变蓄热的变化规律。结果表明：铝骨架的添加强化了蓄热，缩短了融化时间，在复合相变材料孔隙率为0.90、0.85、0.80时，相比于纯石蜡，完全融化时复合相变材料的融化时长分别缩短了68％、75％和80％，而且蓄热过程中温度场更加均匀；验证了铝骨架与石蜡之间由于热导率存在较大的差异，存在的热非平衡效应，且铝/石蜡复合相变材料孔隙率越低，此效应越明显

Numerical simulation of heat storage performance of aluminum/paraffin composite phase change material

Phase change energy storage materials are widely used in the fields of battery thermal management and solar power generation because of their periodic energy storage and release characteristics. However, its further application is limited because of its low thermal conductivity. The addition of high thermal conductivity foam material provides an effective way to solve this problem. In this paper, TPMS is used to generate aluminum foam skeleton. Based on the pore size, the change rule of phase change heat storage of aluminum / paraffin composite phase change materials is simulated. The results show that the addition of aluminum skeleton can enhance the heat storage and shorten the melting time. When the porosity of composite phase change material is 0.9, 0.85 and 0.8, compared with pure paraffin, the melting time of composite phase change material is shortened by 68%, 75% and 80% respectively when it is completely melted, and the temperature field is more uniform during the heat storage process. It is verified that there is a large difference between aluminum skeleton and paraffin due to the thermal conductivity In addition, the lower the porosity of aluminum / paraffin composite phase change materials, the more obvious the effect is.