Dynamic metrics influence on the assessment of daylighting potential use at tropic climate

Abstract

This paper aims to discuss the dynamic metrics Maximum Daylight Autonomy (DAmax) and Useful Daylight Illuminance (UDI) in daylight performance analysi in a tropical climate. Due to the high luminosity in the tropics, the results of these metrics may not provide adequate indications of uniformity and daylight availability in the room. Dynamic simulations were performed in Daysim software of a multipurpose room with a shaded fenestration system. The models combined visible sky factor (VSF high, medium and low) and window-to-wall ratio (WWR 20%, 40%, 60% and 90%), and were analyzed for three situations of minimum illuminance: 100 lux, 300 lux e 500 lux. Spreadsheets were used to customize the UDI and DAmax criteria. DAmax metrics for 100 lux, 300 lux, 500 lux, and three UDI intervals (100-2000 lux, 300-3.000 lux and 500-5.000 lux) were considered, comparing the conventional results with DAmax and UDI proposed by the spreadsheet. The results showed that conventional UDI and DAmax disregard significant occurrences of useful daylight in situations of high luminosity. The study contributes with proposed intervals of UDI and DAmax that showed more coherence in the analysis of luminous performance in the tropics.

Keywords:
Daylighting; Uniformity; Dynamic computational simulation