A Study on Performance Evaluation of Mixed Light Shelf Type According to the Angle of Light Shelf

Abstract

A light-shelf, one of natural lighting methods, has advantages in constructability and economic feasibility in comparison with other passive natural lighting system. A movable light-shelf enables a user in a room to adjust the angle according to his or her preference to control the amount of indoor light. In addition, a light-self serves as a shield to the intense light on window sides when the solar light is strong to relieve glare. The purpose of this study was to investigate the effect of angle adjustment of a mixed type light-shelf on indoor natural lighting and determine efficient light-shelf lighting performance values by using an actual size test-bed. This study was conducted in the following procedures: 1) Previous studies were investigated to analyze the definition of a light-shelf and identify experimental factors for a light-shelf; 2) On the basis of previous studies, the light-shelf experimental factors were set up with reference to the illumination values under clear sky at the meridian transit altitude in each season to perform an experiment; and 3) The performance of the light-shelf was evaluated to examine the effectiveness. The performance evaluation was performed for each season according to the solar altitude of the mixed light-shelf. The indoor distribution of illumination was analyzed on the basis of the day light introduction depending on the angle of the mixed type light-shelf to verify the correlation with variables and the efficacy.