Thermal performance of CaCl2·6H2O/expanded perlite composite phase change boards embedded in aluminous gusset plates for building energy conservation

A simple and flexible way for integrating phase change materials (PCMs) with buildings was presented, which involved forming a PCM into a board and then embedding the board into an aluminous gusset plate that has been widely used in roofs and walls of buildings for decorating. Specifically, a CaCl2·6H2O/expanded perlite (EP) composite PCM with a melting point of 27.38 °C and a latent heat value of 87.44 J/g was employed to fabricate several boards through vacuum compression. The board with a packing density of 300 kg/m3 possesses a large specific heat value of 1933 J/(Kg K) and a low thermal conductivity of 0.168 W/(m K). Furthermore, five pieces of the composite board were embedded into five aluminous gusset plates, followed by being equipped at the roof and the four walls of a small test room, respectively. It is shown the test room equipped with the five composite board-embedded aluminous gusset plates exhibits lower maximum temperature, higher minimum temperature, and reduced temperature amplitude along with more frequency of thermal comfort, as compared with the reference one without the composite boards. And the results from numerical modeling suggest that the optimal thickness of the composite board should be around 5-7 mm. The good thermal performance of the CaCl2·6H2O/EP composite board-embedded aluminous gusset plates make them a novel building material and show great potentials in practical applications.