Realization of a thermal cloak–concentrator using a metamaterial transformer

• Published in: Scientific reports Vol. 8; no. 1; pp. 2493 - 11
• Main Authors: Liu, Ding-Peng, Chen, Po-Jung, Huang, Hsin-Haou
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 06.02.2018; Nature Publishing Group
• Subjects: 639/166/988; 639/301/1023; Coordinate transformations; Heat conductivity; Humanities and Social Sciences; multidisciplinary; Radiation; Science; Science (multidisciplinary); Simulation; Temperature
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-018-20753-y

By combining rotating squares with auxetic properties, we developed a metamaterial transformer capable of realizing metamaterials with tunable functionalities. We investigated the use of a metamaterial transformer-based thermal cloak–concentrator that can change from a cloak to a concentrator when the device configuration is transformed. We established that the proposed dual-functional metamaterial can either thermally protect a region (cloak) or focus heat flux in a small region (concentrator). The dual functionality was verified by finite element simulations and validated by experiments with a specimen composed of copper, epoxy, and rotating squares. This work provides an effective and efficient method for controlling the gradient of heat, in addition to providing a reference for other thermal metamaterials to possess such controllable functionalities by adapting the concept of a metamaterial transformer.