Daylight simulation in urban open space using radiance

This study aims at making simulation system to evaluate the residential environment considering the quality of daylight. First, we discuss new indexes for evaluation of the quality of daylight conditions in urban open space. Second, the basic calculation of illuminance, irradiance, and sky factor are executed. Comparing the distributions of their levels, it was found that there are remarkable differences among the distributions of relative sunshine duration, relative solar irradiance and sky factor. Moreover, they can be effective indexes for the planning method lead up to new urban form. Third, the system is integrated for use in the evaluation of urban residential environment. As a result, it works well to shorten the data manipulation time, to help data sharing and to visualize the quality of daylight in urban open space.