Enhancing the performance of a rooftop solar chimney through flow disturbers

Abstract

Abstract Enhancing the performance of passive solar chimneys constitutes a key point for successful applications in bioclimatic architecture. Present work assesses applications of several kinds of flow disturbers in a rooftop solar chimney, under isoflux heating and windless conditions, and including surface radiative effects. Systematic numerical calculations are conducted aiming a comprehensive analysis, by means of a low-Reynolds turbulence model, being the range of Rayleigh number considered 2.170 × 1012 − 2.170 × 1013. Effect of different geometrical parameters is analyzed, although main attention is posed on the influence of disturbers elements on the thermohydraulic behavior of the established airflow, for obtaining best performance conditions. Some obstacles cause a clear decrease in the efficiency of the system, but given disturbers appropriately located produce valuable enhancements in the thermal or dynamic efficiency. Insertion of intermediate plates proves to be the best option, achieving maximum increases of even approximately 50% in the ventilation capacity.