Effect of various bending angles on a passive light pipe for eco-daylighting systems

Daylighting systems is one of alternative to reduce a high energy consumption that caused by artificial lighting. However the use of passive light pipes in daylighting systems with various bending angles may affect the efficiency of light transfer from the sunlight to the room. Thus this paper is proposed to study the effect of various bending angles on a light pipe. Three bending angles of light pipe, which are 0°, 30° and 45°, were analyzed through the experimental works. A test bed room was constructed in order to simulate daylighting in a room. The results were then visualized in graphs based on the efficiency by considering the maximum average internal illuminance achieved by each light pipe. From the results, it shows that when the bending angle increases, the average internal illuminance decreases. And the highest average internal illuminance was achieved by 0° light pipe.