An experimental study of a facade mounted light pipe

Abstract

An experimental study of a rectangular light pipe mounted on a façade is reported. We used static and adjustable reflectors for enhancing capture and transmission of sunlight through the light pipe. A ray tracing technique was used to calculate the direct sunlight reflected into the light pipe and its transmission to the end of the light pipe. An inter-reflection method was used to calculate the transmission of diffuse skylight and the resulting daylight illuminance in the building interior. The experimental and calculation results demonstrate that daylighting through light pipes can provide acceptable illuminances in deep spaces for almost the whole day under conditions of clear and partly cloudy skies.