Effect of Converging Duct on Solar Chimney

Abstract

Solar chimney is very useful in terms of improving indoor thermal comfort. There are not many studies or simulation that have been done for a converging duct of solar chimney A CFD model of a solar chimney is simulated in this study using ANSYS Workbench 19.2 to find out the effect of convergent of the solar chimney to the velocity in the solar chimney and the air changes per hour in the developed numerical model. Solar chimney is mainly used in hot climate as a passive solar cooling system that can regulate the temperature and increases ventilation. The data needed to simulate the numerical model is taken from previous study. Using fluid flow (CFX) a 2D CFD steady state is simulated by 10 mm of thickness for the model. Four openings were set up to let air leave and enter the cabin. There were four configurations of bottomtop ratio were studied, 1:1, 1:0.8, 1:0.75 and 1:0.5. The 1:0.5 ratio gives the highest outlet velocity while the 1:1 ratio have the highest air changes per hour. Converging the solar chimney bring the solar chimney performance down.