多孔铝骨架/复合相变材料温控性能研究

Research on temperature control performance ofporous aluminum framework/composite phase change materials

相变储能材料(PCM)具有储热密度大、储/放热过程几乎恒温性等优点,是解决电子器件狭小空间下高热流密度问题的理想方案,但相变材料本身的导热系数较低、传热效率差等特性却限制了其应用范围。针对上述难题,以石蜡作为相变材料,通过3D打印制备多孔铝骨架,再采用水浴灌注法将石蜡灌注到多孔铝骨架中,制备出多孔铝骨架/复合相变材料(AS-PCM)。通过实验探究了95%、85%、75%3种孔隙率的温控性能。实验结果表明,添加多孔铝骨架可增强PCM的热传递,从而降低热源温度。在较大的功率下,AS-PCM对传热的改善更为明显。熔化完成前,低孔隙率AS-PCM热沉的底部温度和温度梯度更低,使用多孔铝骨架代替泡沫金属,为提高PCMs的导热性能提供了了新的多孔金属基体。

Phase change energy storage material(PCM)has the advantages of high heat storage density and almost constant temperature in the process of heat storage/release.It is an ideal solution to solve the problem of high heat flux in the narrow space of electronic devices.However,the low thermal conductivity and poor heat transfer efficiency of PCM limit its application.To solve the above problems,the porous aluminum skeleton was prepared by 3D printing using paraffin as phase change material,and then the paraffin was poured into the porous aluminum skeleton by water bath perfusion method to prepare porous aluminum skeleton/composite phase change material(AS-PCM).The temperature control performance of three different porosity of 95%,85%and 75%was explored through experiments.The experimental results show that the addition of porous aluminum skeleton can enhance the heat transfer of PCM,thus reducing the temperature of heat source.At higher power,AS-PCM improves heat transfer more obviously.Before melted,the bottom temperature and temperature gradient of the low porosity AS-PCM heat sink are lower.The use of porous aluminum skeleton instead of foam metal provides a new porous metal matrix for improving the thermal conductivity of PCMs.