| During sunny conditions, surface temperatures on masonry façades can rise to over 40 degrees above ambient temperatures. Conventional wall designs exclude this solar heat through the use of thermal insulation. However, air that is drawn from the outdoors, between the façade and sheathing, can be used to recover heat from the masonry façade. The system, which utilizes a Dynamic Buffer Zone (DBZ), acts as a solar air collector. This system can provide an effective way to preheat ventilation air at little to no extra cost while not compromising the architectural features of the masonry wall system. An analytical model was developed to predict the amount of heat recovery. The analytical model was verified by comparing results with a commercial Computational Fluid Dynamics software package and by conducting laboratory experiments. Results indicate that the DBZ as a solar air collector can achieve effective solar efficiencies as high as 33%. |
