Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6731059 | Energy and Buildings | 2015 | 19 Pages |
Abstract
Despite the well-known properties of organic phase change materials (PCMs), drawbacks including high phase transformation point, fluid leakage, and low thermal conductivity limit their practical applications. In this study, a kind of PCMs with low melting point (below 25 °C) was prepared using capric and lauric acid as substrates with additive oleic acid (C-L-O acid). C-L-O acid was then impregnated into worm-like expanded graphite (EG) to form the shape-stabilized PCMs (SPCMs) without any chemical reaction. EG was used to be not only a heat transfer intensifier, but also a shape-stabilized container for C-L-O acid. The melting enthalpy (ÎHm) of the SPCMs (mass ratio of EG to C-L-O acid was 1:35) was calculated to be 114.65 J/g, which was extremely close to the value of original C-L-O acid (115.91 J/g). The thermal conductivity of the SPCMs (1:5) was measured to be 3.15 W/m K, which was 22.5 times higher than that of original acid (0.14 W/m K). The SPCMs also showed good thermal reliability after thermal treatment cycles measurements. With consideration of latent heat and thermal conductivity, the SPCMs (1:15) were eventually selected as the optimal SPCMs with their ÎHm of 109.18 J/g and thermal conductivity of 1.95 W/m K. These composite SPCMs can be easily mass prepared and further used as potential materials for practical radiant cooling system.
Keywords
Related Topics
Physical Sciences and Engineering
Energy
Renewable Energy, Sustainability and the Environment
Authors
Xuehui Tang, Bei Zhu, Minghan Xu, Wei Zhang, Zhi Yang, Yafei Zhang, Guilin Yin, Dannong He, Hao Wei, Xiaoqiang Zhai,