纳米颗粒对十四烷相变材料热物理性质的影响

Effect of Nanoparticles on Thermophysical Properties of Tetradecane Phase Change Materials

以十四烷作为基液,纳米颗粒Al_(2)O_(3)、CuO、MgO和多壁碳纳米管(MWCNT)为添加剂,分别制备质量分数为1%、2%、3%、4%和5%的十四烷纳米复合相变材料,并对其进行形貌结构表征和热物理性质研究。结果表明:纳米颗粒的加入使相变温度变化不大,潜热值降低了0.66%~14.43%;热导率明显提升,并且随着纳米颗粒质量分数的增加而增加;纳米复合相变材料在50℃以上才会出现分解,高于应用范围;与纯十四烷相比,纳米复合相变材料的相变时间明显缩短。最佳纳米颗粒为MWCNT,最佳质量分数3%,热导率0.1897 W/(m·K),潜热值199.7 J/g,可作为一种潜在的相变蓄冷材料。

Tetradecane nanocomposite phase change materials with mass fractions of 1%,2%,3%,4%,and 5%were prepared using tetradecane as a base fluid,and nanoparticles Al_(2)O_(3),CuO,MgO,and multi-walled carbon nanotubes(MWCNT)as additives,respectively.The morphology structure characterization and thermophysical properties were studied.The results showed that the addition of nanoparticles caused little change in the phase change temperature,and the latent heat values were reduced by 0.66%to 14.43%;thermal conductivity was signif⁃icantly enhanced and increased with the increase in the mass fraction of nanoparticles;decomposition of the nano⁃composite phase change materials occurred above 50℃,which was higher than the range of application;phase change time of the nanocomposite phase change materials was significantly shortened compared with that of pure tet⁃radecane.The optimal nanoparticle was MWCNT with an optimal mass fraction of 3%,a thermal conductivity of 0.1897 W/(m·K),and a latent heat value of 199.7 J/g,which can be used as a potential phase-change cooling storage material.