Abstract
Tubular daylighting devices are systems that collect and channel daylight from building roofs into deep interior spaces. To meet high standards of building energy efficiency and glare-free indoor environments, tubular daylighting device technologies have been rapidly and continuously evolving over the past two decades. However, this pace has been counteracted by a lack of reliable computer design tools. This article presents the development of analytical models to compute the optical characteristics (transmittance, reflectance, and layer absorptances) of various types of complex tubular daylighting devices New metrics for the optical and lighting performance are developed. The optical models are based on the ray-tracing technique, and account for the spectral (monochromatic) or broad-band optical properties of tubular daylighting device glazing panes. Experimental validation of these models is presented in an accompanying paper (Laouadi et al., Citation2013c).
Acknowledgments
Abdelaziz Laouadi, PhD, Member ASHRAE, is Senior Research Officer. Anca D. Galasiu is Technical Officer. Hamed H. Saber is Associate Research Officer. Chantal Arsenault is Technical Officer.