Computational fluid dynamics simulation of a designed envelop contenting phase change material and imposed solar heat flux and ambient air

Buildings are one of the largest consumers of energy for cooling and heating systems to provide the comfort temperature for human living. The use of smart materials or phase change materials (PCMs) pave the road to prevent heat loss of buildings. This material is injected into a block called envelop, employed in Buildings' roof and floor. In the present study, a envelop filled PCM with a melting temperature of 16.5 degrees C was designed and simulated by computational fluid dynamic (CFD) and was imposed surrounding air (robin boundary condition). Moreover, the effects of Buoyant force, creating free convection mechanism due to melting PCM and density change with temperature, was considered in this numerical method. Thus, this unsteady numerical study focused on three inclined angles (30 <= theta <= 60) and three solar heat flux (200 <= q <= 300 m2W ) imposed in 12 h, whose effects were analyzed on the melting fraction, temperature contours for 12 h and melting fraction percentage at passing time after 12 h. The obtained results showed that the phase change line was perpendicular to gravity vector due to high buoyant force. Moreover, investigation of inclined angles was a vital parameter in PCM melting process. Furthermore, the indoor of building was safe from hot air outdoor at least 9 h exposing the worst solar heat flux.

Automated summary

Buildings consume a large amount of energy for cooling and heating, but the use of smart materials or phase change materials (PCMs) can help prevent heat loss. This study designed a PCM-filled envelope with a melting temperature of 16.5 degrees C for use in buildings' roofs and floors. The results showed that the phase change line was perpendicular to gravity due to high buoyant force, and the inclination angle played a vital role in the PCM melting process. Additionally, the indoor space of the building remained safe from hot outdoor air for at least 9 hours under the worst solar heat flux.