Abstract
The goal of this study is to provide building designers with daylighting and sunlighting performance data and design guidelines for sunlit atria with different well and canopy configurations which can be referenced during the early stages of an atrium design. Several instrumentation systems were developed to overcome the limitations of conventional photometric instruments. The instrumentation systems include a video-based luminance mapping system to determine geometric and photometric daylighting parameters and an integrating box to measure hemispherical transmittance of canopy systems. Then, a total of seven different atrium well configurations and a total of thirty-six atrium canopy configurations were parametrically evaluated with physical scale models in terms of their impacts on the illuminance levels on the atrium floor and luminance distributions on the walls under different sky and sunlight conditions. To obtain daylighting performance data, lighting measurements were conducted in a large-scale sky simulator which can create clear and overcast skies. To obtain net sunlighting performance data, lighting measurements were conducted with an artificial sun at an outdoor location at night. Initial data analysis for diffuse skies was performed with Base Case Daylight Factors obtained without canopy. Then, Effective Transmittances of each canopy system at different atrium well configurations were determined as the ratio of canopy-covered Daylight Factors (DF) to the Base Case Daylight Factors. In addition, daylight luminance distributions and Luminance Ratios on the atrium walls were determined from luminance distribution maps captured by the video-based luminance mapping system. Data analysis for sunlit atria was performed with Sunlight Illuminance Ratios (SIR) obtained with and without canopies. Furthermore, a new method was developed to quantitatively evaluate sunlight patches on atrium walls using the video-based luminance mapping system and physical scale models. With this method, it is possible to account for the locations and sizes of sunlight patches...
Song, Kyoo Dong (1993). Illuminance levels and luminance distributions in sunlit atria with different canopy systems and well configurations. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -1531029.