Heat flux effect of thermal metamaterials

In this study, we investigated the heat flux effect of thermal metamaterials, which can effectively suppress heat propagation, through the three-dimensional finite-difference time-domain techniques. When a concrete block was heated or cooled, different heat propagation characteristics were demonstrated according to the plate-shaped meta-structure embedded in the concrete block. Under the assumption that the overall thickness of the plate-shaped meta-structure is constant, separating the plate-shaped meta-structure into two or more layers has a better heat blocking effect than using a single plate-shaped meta-structure. In addition, the thermal blocking efficiency varies depending on the thermal metamaterial used as the plate-shaped meta-structure. The thermal blocking efficiency of the thermal metamaterials was better in the order of air, aerogel, Styrofoam, and paraffin. The result indicated that the heat transfer in a concrete block can be manipulated by controlling the material, number, and spacing of the plate-shaped meta-structures, and the proposed plate-shaped meta-structures can be applied to reduce the thickness of a concrete block containing an insulating layer used in buildings.