CFD study of Malaysian roof attic with Phase Change Material (PCM26-29) as a passive cooling for buildings under Malaysian climate

Malaysia lies near the equator line with hot and humid weather conditions all year round. Thermal comfort inside residential houses becomes a necessity and increasingly important, especially with the recent increase in global warming. Phase Change Material (PCM) offers passive cooling options for buildings, but investigations in Malaysia are still new and scarce. This study investigates the feasibility of using PCM 26–29 in Malaysian roof structures by using a three-dimensional symmetrical Computational Fluid Dynamics (CFD) model. A steady-state condition was solved to simulate the peak temperature when the PCM absorbs the excess heat in the attic. Two cases are proposed based on the thermal performance using different amounts of PCM mass: 12 kg in Case 1 and 24 kg in Case 2. This study shows that the 12 kg PCM integration leads to a 7.8% reduction in indoor temperatures but doubling the PCM mass only results in a diminishing return of another 3.6% reduction in temperature, presumably due to the low thermal conductivity of PCM. These findings confirm the potential of PCM as an efficient passive cooling strategy, but careful designs of the capsule may be needed to increase the surface contact area, particularly if high PCM mass is to be considered. In this way, the dependency on active cooling, such as air conditioning systems, can be reduced. Further experimental work is recommended to confirm the findings. This research offers valuable insights for integrating PCM into buildings. The positive impact of reducing thermal load in indoor areas provides a sustainable solution in residential areas