Climatic cycling assessment of red clay/perlite and vermiculite composite PCM for improving thermal inertia in buildings

One of the ways to reduce building energy is to actively release or store the thermal energy through phase change materials (PCMs) to use heat energy efficiently. PCMs have the major drawback of leaking during the solid-liquid phase transition. Therefore, PCMs must be applied to buildings through phase stabilization. Expanded vermiculite (EV) and expanded perlite (EP) are porous nanoclay materials possessing excellent properties as containers for PCMs. The applied PCM is n-octadecane, which belongs to the organic paraffin series, is thermally stable, and has high latent heat capacity. Shape-stabilized PCM (SSPCM) is stabilized by the vacuum impregnation method by physical bonding only, without chemical reaction. The thermal properties of the prepared SSPCM are analyzed by DSC, TGA, TCi, and enthalpy calculation. The RC-SSPCMs panel is developed using red clay (RC), an eco-friendly building material. The thermal performance of the manufactured panels is analyzed by the climate cycling test, which considers the daily temperature behavior. In the analysis of the thermal performance, the peak temperature reduced by up to 1.6 °C during the phase transition of RC/EP-SSPCMs (P10), the time-lag effect in the phase change transition of RC/EP-SSPCMs (P10) occurred for up to 1.33 h.