Abstract
In this study, we compared the analytical values of light transmittance through venetian blinds calculated using the lighting simulation program Radiance with measured values of the transmittance.
First, we measured the transmittance using a box with blinds on a building roof in summer and winter, and then, we simulated this box using Radiance under the same conditions.
We investigated the appropriate conditions for simulation, including the number of planes in the curved surface of the blind slats and the slat reflectance for specular and diffuse reflections.
Overall, the analytical values of transmittance are 0-10% lower than values measured.