This study investigates the use of daylight as a primary source of illumination, given its contribution to reduced energy consumption and enhanced visual comfort in indoor environments. Daylight is an essential requirement in indoor environments that are used intensively throughout the day. Thus, its effective admission and distribution are necessary for both visual comfort and sustainability. This study proposes the Di-ARCieling design, a ceiling system consisting of circular reflective surfaces arranged in two different orientations (a Two-Way Circular Ceiling System), as a strategy to increase the use of daylight in interior spaces. This ceiling design aims not only to admit incoming daylight but also to direct it deeper into the interior space, ensuring that its presence is prolonged. The daylight performance of the Di-ARCieling system was evaluated using VELUX Daylight Visualizer simulation software. The illumination performance of the system was comparatively analyzed through simulations conducted at different times of the day and representative periods of the year. The findings revealed that the Di-ARCieling system could function as an effective daylight redistribution strategy when integrated with the ceiling. It was determined that the illumination levels in the deeper areas of the interior space increased by approximately 20–35% compared to the illumination levels of the flat ceiling. Accordingly, the Di-ARCieling system can be considered an innovative and passive daylight utilization strategy aimed at increasing visual comfort and daylight efficiency in interior spaces.
Şeref et al. (Sun,) studied this question.