Barocaloric Material with High Thermal Conductivity for Room-Temperature Refrigeration

• Published in: Journal of thermal science Vol. 32; no. 6; pp. 2115 - 2125
• Main Authors: Zhu, Liutao, Dai, Zhaofeng, Gao, Yuanzhi, Wu, Dongxu, Wang, Changling, Zhao, Dongliang, She, Xiaohui, Ding, Yulong, Zhang, Xiaosong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.11.2023; Springer Nature B.V
• Subjects: Binary system; Classical and Continuum Physics; Engineering Fluid Dynamics; Engineering Thermodynamics; Graphene; Heat and Mass Transfer; Heat conductivity; Heat transfer; Numerical models; Phase transitions; Physics; Physics and Astronomy; Refrigeration; Room temperature; Thermal conductivity; Transition temperature; plastic crystal; performance enhancement; barocaloric refrigeration; graphene; numerical simulation
• ISSN: 1003-2169; 1993-033X
• DOI: 10.1007/s11630-023-1867-y

Barocaloric refrigeration technology, one of the caloric-effect refrigeration technologies, is drawing more and more attention. Neopentyl glycol (NPG) was reported to have a giant barocaloric effect, making it a potential barocaloric material. However, the high solid-solid (S-S) phase transition temperature and low thermal conductivity hinder the application of NPG in barocaloric refrigeration. This work lowers the S-S phase transition temperature and improves the thermal conductivity of the NPG-based barocaloric material. An NPG/TMP (TMP: Trimethylolpropane) binary system with an S-S phase transition temperature of 283.15 K is prepared, in which the mass ratio of TMP is 20%. Graphene is then added to the binary system to enhance thermal conductivity, and the optimal mass ratio of graphene was determined to be 5%. The thermal conductivity of this composite is 0.4 W/(m·K), increased by 110% compared to the binary system. To predict the effect of enhanced thermal conductivity on the cold-extraction process of the barocaloric refrigeration cycle, a numerical model is developed. The results show that the cold-extraction time of the barocaloric refrigeration cycle utilizing the composite with 5% graphene as the refrigerant is shortened by 50% compared with that using the binary system.