Predicted Performance of Shading Devices for Healthy Visual Environment

The main purpose of using a shading device is usually to prevent excessive sunlight from delivering into the building and to distribute daylight entering a building more evenly in space. However, in the design of a vertical fenestration system, there are a variety of considerations related to the building type and daylighting potentials such as: latitude, climatic characteristics, the position of the sun and outdoor obstructions. To enhance the performance of sun lighting control, a shading device should play a more efficient role according to the building shape and orientation. This paper examines the method designed to improve both the indoor natural illuminance and open view for a better visual environment. The main aim of the proposed approach is to provide a simplified calculation for the several conditions of shading device shapes based on the computer simulation analysis. The proposed method was conducted by dividing the internal illuminance into four types of the shading device systems due to the direct sun radiations. This was calculated by a Desktop Radiance program. The room dimensions were based on a unit module of apartments of 6 m (width) × 6.9 m (depth) × 2.7 m (height) with a window measuring 4.5 m × 2.43 m. The variables considered were: a basic horizontal louver, a blind system and a proposed experimental shading device.

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