Numerical Study and Geometrical Investigation of an Inclined Passive Wall Solar Chimney over the Ventilation Performance of an Attached Room

The present numerical work investigates by means of Constructal Design the influence of the geometry of an inclined passive wall solar chimney on the ventilation performance of an attached room. The main purpose is to maximize the mass flow rate of air in the chimney/attached room. The problem is subjected to two constraints: the chimney and room areas. Three degrees of freedom are investigated: the ratio between the exit and inferior bases widths of the chimney (W-e/W-g), the ratio between the width of the chimney inferior basis and the absorber wall height (W-g/H-a), and the ratio between the opening that connects chimney and room and the absorber wall height (H-i/H-a). It is considered unsteady, incompressible, free convective, turbulent flows in a two-dimensional domain. The finite volume method is used to solve the time-averaged equations of continuity, momentum and conservation of energy. For closure of turbulence, it is employed the k-e model. Results showed that the best geometric configuration led to a mass flow rate 5.7 times superior than the worst configuration, showing the importance of solar chimney desing in this problem. Moreover, a strong sensibility of the investigated ratios on the mass flow rate was noticed.