Abstract
Increasingly, passive ventilation solutions are receiving considerable attention for inducing natural ventilation in dwellings regarding operation costs, energy demands, and carbon dioxide emissions. Solar chimney, in particular, is a promising alternative to enhance thermal and ventilation performance for the indoor environment by using convection of air heated by passive solar energy. The present study focuses on achieving optimum natural ventilation rate by incorporating solar chimney into a single room in a hot climatic context. Specifically, a mathematical model is developed through an overall energy balance on the solar chimney. This model examines a wide range of geometry parameters under real weather data to determine the optimum design solutions for the solar chimney. Furthermore, the model predicts the temperatures of the glazing and the black painted absorber as well as air velocity exiting from the chimney. The analytical results showed that an optimum air flow rate of 0.019-0.033 m(3)/s was achieved by 88.2% during the daytime when the dimensions of a"proposed solar chimney are 45 degrees inclination angle, 1.4 m length, 0.6 m width and 0.20 m air gab. Moreover, Computational Fluid Dynamics (CFD) was applied to predict space flow pattern using CFD module in DesignBuilder software, which is based on Energy Plus dynamic simulation engine. The renormalization group (RNG) k-epsilon turbulence model was applied to solving the mass and energy equations within the solar chimney. Comparisons of the model predictions with CFD calculations and bibliographic experimental work outline the validity of the model. (C) 2016 Elsevier B.V. All rights reserved.