Paper Conference

Proceedings of BauSim Conference 2006: 1st Conference of IBPSA-Germany and Austria


A method for calculation of bi-directional solar properties of a venetian blind

D.C. Curcija, N. Stojanovic

Abstract: Venetian blinds are widely used as shading devicesfor windows. Methods for simulation of blinds areneeded because measurements of their properties areexpensive and quite involved. This paper presentsnovel method (named “directional diffuse method”)for calculation of bidirectional properties of a venetian blind. The shadowing of blind slat surfaces istaken into account during the calculation of thediffuse portion, resulting in a more realistic, nonuniform distribution of the scattered (diffuse)component. The method is applicable to devices withflat or curved slats. The resulting BTDF/BRDF canbe used with the glazing layers BTDF/BRDF and fullmatrix calculation can be performed to get systemperformance with full spatial resolution. Thismethodology has been developed and implemented inthe new version 6.0 of WINDOW program and hasbeen successfully validated against limited amount ofmeasurements and ray tracing simulations.
Pages: 16 - 18