空穴效应下泡沫金属复合相变材料热性能数值模拟
Numerical Analysis on Thermal Performances of Metal Foam Composite Phase Change Materials Under Cavity Effects
潘涵婷 1许多 1徐洪涛 1罗祝清1
作者信息
- 1. 上海理工大学 能源与动力工程学院,上海 200093
- 折叠
摘要
在三维泡沫金属复合相变材料(PCM)基础上,构建了随机分布空穴模型,采用多松弛时间格子Boltzmann方法,从孔隙尺度分析了不同空穴体积分数、分布位置及泡沫金属与PCM导热系数比下的空穴效应.结果表明,随着空穴体积分数的增加,减缓了复合PCM的传热速度,并降低了潜热储能的能力.在Fourier数Fo = 0.7时刻下,当空穴体积分数分别为 2.4%,7.6%和 11.7%时,相较于无空穴情况下的储热量分别减少了 3.2%,9.0%和 13.0%.当体积分数为 3%的空穴集中在热壁面侧时,其对复合PCM熔化过程的阻碍作用最显著,此时空穴层相当于绝热层,使复合PCM的整体熔化时间延长了 6.1%.为削弱空穴效应,可选择导热系数比超过 100 的泡沫金属骨架来提高其在传热中的主导作用.
Abstract
A randomly distributed cavity model was constructed for 3D metal foam composite phase change ma-terials(PCMs),and the multi-relaxation time lattice Boltzmann method was used to explore the cavity effects with different volume fractions,distribution locations,and thermal conductivity ratios of metal foam to PCM at the cavity scale.The results show that,with the increase of the cavity volume fraction,the heat transfer rate and latent heat storage capacity of composite PCMs would decrease.At a Fourier number of 0.7,compared to the case without cavity,the heat storage decreases respectively by 3.2%,9.0%,and 13.0%for a cavity volume fraction of 2.4%,7.6%,and 11.7%,respectively.The significant hindering effect on the melting process of com-posite PCMs occurs in the case of cavities with a volume fraction of 3%and concentrated near the high-tempera-ture wall.The cavities act as an adiabatic layer,extending the complete melting time of composite PCMs by 6.1%.To weaken the cavity effect,the metal foam skeleton with a thermal conductivity ratio of more than 100 can be selected to improve its leading role in heat transfer.
关键词
相变/泡沫金属/空穴/熔化/格子Boltzmann方法Key words
phase change/metal foam/cavity/melting/lattice Boltzmann method引用本文复制引用
基金项目
上海市自然科学基金(面上项目)(20ZR1438700)
出版年
2024
国家科技期刊平台
NSTL
维普
万方数据