Synthesis and characterization of PCM based insulated concrete for thermal energy storage

Abstract

Phase change materials (PCMs) are an innovative solution in a thermal energy storage system that can contribute efficiently to the improvement of the energy performance in the building. The phase change is the latent heat of storage materials that can store a large amount of thermal energy in its phase change from solid to liquid and vice versa. The heat storage/release mechanism of PCM is due to its sensitivity to melting/solidifying processes. Optimized ratios of PCM in concrete is essential for effective thermal storage system and strengthen physical characteristic. In this research work, dip coating of phase change materials of melting temperature 17°C to 50°C was done for coarse aggregate in the ratios via 25%, 50%, 75%, and 100 v/v% with the cement. The compressive strength of PCM-based coated coarse aggregated 0%, 25%, 50%, 75%, and 100% was investigated after 7, 14, and 28 days' ages. Encapsulated coarse aggregates (ECA) of different ratios were compared for thermal energy conductance while keeping compressive strength as a key parameter. Temperature differences of 12.35, 15.25, 16.35, 17.5, and 20.3°C were observed for ECA-100, ECA-75, ECA-50- ECA-25, and NCA, respectively in 12 h. The encapsulated PCM-based coarse aggregate concrete was characterized for physical, thermal conductance, and surface morphology. It was found that ECA-50 offers optimum storage of latent heat and reasonable compressive strength of concrete. However, an adverse impact was found regarding compressive strength as the PCM ratio increases above 50% v/v%, which can be maintained by bonding additives CNTs and GO.