CH-09-016 -- A Detailed Model to Determine the Effective Solar Optical Properties of Draperies PDF

Drapes have the potential to reduce peak cooling load and annual energy consumption because they can be used to control solar gain. Thus, the need to model a drapes in a glazing system analysis is important. A detailed model that can be used to estimate the spatially averaged (effective) solar optical properties of a drapery is presented. This model approximates a drapery as a series of uniformly arranged rectangular pleats. The effective solar optical properties of the drapery are then determined by considering a representative enclosure. The solar properties of the fabric are incidence angle dependent, and the effects of beam and diffuse components, in both reflection and transmission, are included. Furthermore, the model can be applied to fabrics with differing front and back properties. The model therefore offers new possibilities in calculating the effective solar optical properties of draperies made with practically any fabric. Results are presented for both incident beam and diffuse radiation.