A combined, large, multi-faceted bulbous façade glazed curtain with open atrium as a natural ventilation solution for an energy efficient sustainable office building in Southern China

This paper investigates the ventilation performance of a stack system built with a bulbous façade glazed curtain and an open atrium in a six-storey office building, in DongGuan eco-park in southern China. Sustainable development, energy efficiency, indoor environmental quality and thermal comfort are the key criteria for the design; incorporating LingNan architectural cultural elements, with large open atrium for natural ventilation and openable windows to allow air movement throughout the building. The high energy load accentuated by the glazing would be offset by stack ventilation, to provide indoor circulation of air to maintain a satisfactory level of thermal comfort in spring/autumn, without relying on air conditioning, thus saving energy consumption (about 60%). Computational Fluid Dynamics (CFD) simulations were conducted to determine the efficacy of natural ventilation to illustrate the heat storage, dissipation and transfer within the building. The ventilation and heat dissipation performance of the stack system in the bulbous atrium in different seasons are illustrated with four different percentage of inlet and outlet openings. In summer and autumn/spring, good natural ventilation performance in the building can be achieved by the bulbous façade layer caused by buoyancy force and wind pressure and in the atrium courtyard. Sound ventilation performance can be achieved in rooms on most floors, while worst ventilation performance is expected in the top floor. The design of the bulbous façade with a large open atrium can provide effective ventilation efficiency for a better indoor thermal environment by strategic use of building self-shading and natural ventilation.