Effects of Outlet Area on the Nusselt Number of the Solar Chimney

Solar chimney has been applied widely in many aspects, such as civil engineering and building physics and demonstrated to be a good solution for natural ventilation of dwellings. It uses absorbed solar radiation to create stack effect which induces air flow and increases ventilation of building. Therefore, solar chimney is one of the most common methods used for energy saving, especially in the field of green design. In this study, we examined a solar chimney integrated with a cover plate at the outlet of the chimney. In other words, the outlet area of the chimney is contracted. A Computational Fluid Dynamics (CFD) model was utilized to simulate the air flow and heat transfer throughout the air channel. The effects of lowering the outlet area were investigated at various air channel heights and gaps. The results indicate that limiting the outlet area strongly affected the computed Nusselt number. Keywords: Solar chimney, natural ventilation, outlet area, CFD, renewable energy, Nusselt number.