Development and thermal performance of a wall heat collection prototype

A wall-integrated solar heating system refers to an architectural design approach that combines hot water generation with the buildingʹs construction system. This combination allows this system to feature a hot water generation function and become part of the building facade. This study attempts to develop a wall heat collection prototype, which has been simplified to a rectangular natural circulation loop, according to the practical boundary conditions and heat transfer mechanisms. The heat transfer performance was investigated experimentally. The results showed that the average velocity of the fluid increases with an increase in the heating power and aspect ratio or a decrease in the length of the cooling section. A Reynolds number correlation, based on our experimental data and the Rayleigh number, is proposed.