An Experimental Investigation of Macro‐Encapsulated Nano‐Enhanced OM Phase Change Materials for Enhancing the Thermal Performance of Building Bricks

The present study investigates experimentally the thermal performance analysis of bricks integrated with organic mixture (OM) phase change materials (PCMs). A brick measuring 22 cm × 10 cm × 7.5 cm (length × width × thickness) was considered for analysis under three configurations. Brick‐A served as the reference specimen without PCM (mortar layer only), while Brick‐B was incorporated with OM 35 PCM, and Brick‐C with OM 42 PCM. For the PCM integration, a macro‐encapsulation technique was adopted, in which the PCM is considered as the core and an aluminium sheet container as the shell. A macro‐encapsulated PCM layer of size 22 cm × 10 cm × 1.5 cm was prepared using mortar and attached to the exterior surface of the brick. A constant heat input (in a span of 5 min for a 250 min duration) of 36 W over an area of 0.022 m 2 (equivalent to a peak solar intensity of 1636 W/m 2 under Indian hot climatic conditions) was applied to the exterior surface of the brick. The peak solar intensity (1636 W/m 2 ) is the ratio of heat input (36 W) to the surface area (0.022 m 2 ) of the bricks. The primary objective was to evaluate the effect of the macro‐encapsulated OM PCM layers on the thermal performance of the bricks. The comparison of the inner and outer surface temperatures of the PCM‐integrated bricks (B and C) with that of the reference Brick‐A revealed significant improvements in their thermal performance. Compared to the conventional brick (Brick‐A), the PCM‐integrated bricks showed substantial reductions in inner surface temperature rise, with values decreasing from 19.84°C to 6.51°C for Brick‐B and 10.48°C for Brick‐C. The average temperature reduction observed for Brick‐B and Brick‐C was 91.64% and 87.8%, respectively. Similarly, the reduction in conductive heat transfer was 47.82% for Brick‐B and 46.75% for Brick‐C. The maximum temperature reduction compared to the reference Brick‐A was 7.01°C for Brick‐B and 4.8°C for Brick‐C. These results demonstrate the effectiveness of macro‐encapsulated OM PCMs in enhancing the thermal performance of building bricks, highlighting their potential for passive thermal energy management in building envelopes.