A theoretical and numerical analysis of solar chimney in multi-storey atrium building

Abstract

Current research efforts on solar chimney are much on those configurations with single space or single vent, hampering its applications in complex buildings. To expand its implementation, the viability of solar chimney in multi-storey atrium buildings was explored numerically and theoretically. It was known that its natural ventilation performance can fulfil the WHO requirements (i.e., 6 air change per hour, ACH) even under low solar radiation of 200 W/m2 if it is appropriately designed, such as cavity gap (d), cavity height (Hc), solar radiation (Q), and window width (W). Its natural ventilation rate was found to be positively linear to the exponential form of the analyzed factors in this study, including cavity gap (d0.63∼0.69), cavity height (Hc0.59∼0.60), solar radiation (Q0.42∼0.43), and window width (W0.14∼0.20). The impacts of cavity gap and solar radiation are relatively weaker for big space such as atrium than those scenarios with single-space ventilation in the literature. The volume of the connected space was found to affect its natural ventilation performance, where the obtained ventilation rate of 4-storey is averagely 5.1 % lower than those of 3-storey buildings. A theoretical model was developed and experimentally validated, for the first time, to predict the natural ventilation rate of solar chimney when it is applied to the atrium with multiple air inlets. It was also noticed that the same theoretical model can be applied to the atrium buildings with odd and even storeys, but the area coefficients are different. The research outcomes of this study confirm the viability of solar chimney in complex buildings and offer a theoretical foundation for its implementation.