Performance Assessment of Light Shelves System in Office Buildings

This research investigates the performance of light shelves to enhance daylighting and visual comfort within indoor spaces. Theoretical simulations were used to assess the impact of light shelves on daylight performance, utilizing metrics such as Useful Daylight Illuminance (UDI), Daylight Factor (DF), and Daylight Glare Probability (DGP). The research includes an in-depth analysis of an office building in Tehran, Iran, utilizing the Radiance software. A total of ۱,۲۹۶ simulations were performed under varying conditions to examine the effectiveness of light shelves. The outcomes of the study question several widely accepted notions about the advantages of light shelves. Although horizontal light shelves did increase illuminance beyond the height of the window in many cases, the area that experienced substantial daylight improvement was quite limited. It is commonly believed that light shelves decrease glare by providing shade near the window; however, the simulations revealed that in about ۳۰% of the scenarios, horizontal light shelves actually led to an increase in illuminance near the window, potentially exacerbating glare. Furthermore, the study observed a reduction in the uniformity of illuminance across the space due to the presence of light shelves. These challenges might be addressed by using a moveable light shelf, which allows for greater adaptability and precision in managing lighting conditions.

کلیدواژه ها:

daylight factor ، useful daylight illuminance ، daylight glare probability ، light shelf ، Radiance