A STUDY OF THE EFFECTS OF EXTERNAL SHADING DEVICES ON DAYLIGHTING AND THERMAL PERFORMANCE FOR RESIDENTIAL BUILDING USING COMPUTATIONAL BUILDING PERFORMANCE SIMULATIONS

Abstract

In Singapore's residential building, where electricity for thermal comfort tends to be a major factor of energy use, the concept of passive design in relation with thermal and daylighting has been the most prominent issue. Shading device is one of many passive design approaches that can be used to minimize indoor heat gain. Besides preventing solar heat gain, it must also provide adequate ventilation, admit maximum diffuse daylight, reduce glare condition and exclude radiant heat. Taking into consideration the fact that controlling consumption of natural energy is able to impact positively or negatively on building performance, utilizing shading device needs a careful study. For this reason, investigation of those parameters was conducted comprehensively. This study used two stand-alone computational building performance simulations. They were Lightscape simulation for lighting performance and Computational Fluid Dynamics (CFD) for thermal performance. The simulations give significant predictions. Then, they provide comparative data and analysis of the effect of shading devices on daylighting and thermal performance for Singapore's residential building, which are important to achieve their effective functions. The observed behaviors of shading devices in controlling all above parameters present significant information for making reasonable design decision. Besides to optimize the design, based on the needs, objectives and environmental conditions, the selected shading device could be determined to enhance one or more parameters properly from which thermal comfort and energy efficiency strategies can be drawn. This study also offers a methodology to simulate solar radiation on the domain of computational fluid dynamic (CFD) which can spur the further application of the effects of solar radiation on thermal performance for other building types.