Abstract
Studies using metrics related to dynamic sky conditions for indoor daylight performance assessment in urban environment are rare in tropical latitudes. This study applied one of these metrics, the spatial Daylight Autonomy (sDA 300,50% ≥75%, IES LM 83-12) for Cuiabá (15ºS, 56ºW, Brazil), a savanna climate city with a high frequency of partly cloudy skies. Parametric simulations were used to investigate the availability of daylight in dense urban areas. So daylight conditions inside a reference room with varied depths located within a continuous urban canyon were simulated with Radiance/Daysim in Grasshopper/Honeybee. Dimensions of the street and heights of front buildings (obstructions) are also varied in order to observe the relation between the sky angle and the sDA, for the four main cardinal directions. The results of regression analysis for this case study showed that among all evaluated parameters, room depth tended to be the most relevant for the optimization of indoor daylight. Finally, limitations of this approach and opportunities for further investigations were discussed.
Keywords:
Daylight; Illuminance; Computer simulation; Spatial Daylight Autonomy
Source: adapted from Kottek et al. (2006) and United Nations (2014).
Note: M = Month (i.e., 1=January); and A: Annual.Source: adapted from ClimateConsultant
Note: Left: the reference room. Above: The continuous urban canyon containing the reference room. Double arrows indicate the variable dimensions of street width, front obstruction height, and room depth
