Phase-change materials can be used to effectively realize the high efficiency and reasonable utilization of energy. We present a nanocomposite phase-change material, which is assembled mainly with filled nanoparticles and nanoporous substrates. Molecular dynamics method was used to simulate the phase-change behavior and thermal properties of metallic nanoparticles, nanoporous substrate, and composite. Thermal properties of metallic nanoparticles and nanoporous substrate were discussed under different sizes and conditions and compared with the thermal properties of composite materials. The research shows that the melting point of copper nanoparticles increases gradually with size and it is lower than that of bulk copper. Meanwhile, the heat capacity of copper nanoparticles is higher than that of bulk copper. Nanoporous SiO2 substrate has no fixed melting point but has a large span of the melting zone, and its heat capacity increases with size or temperature and is significantly smaller than that of bulk SiO2. The results show that the melting points of Cu/SiO2 composites are higher than those of Cu nanoparticles and substrate, which means that composites enhance the structural stability. Meanwhile, the filled Cu nanoparticles effectively improve the heat storage characteristics of the nanoporous substrate.
LI Jing
,
LIAO Qiang
. Thermal properties and phase transition properties of Cu/SiO2 nanocomposites[J]. Journal of University of Chinese Academy of Sciences, 2018
, 35(2)
: 248
-253
.
DOI: 10.7523/j.issn.2095-6134.2018.02.015
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