A method of estimating the spatiotemporal distribution of reflected sunlight from glass curtain walls in high-rise business districts using street-view panoramas

Abstract

• A novel method is proposed to estimate the spatiotemporal distribution of reflected sunlight. • A novel panoramic transformation algorithm to qualify sunlight reflection duration. • A new method to estimate time-specific reflection intensity from glass curtain walls. • The spatiotemporal distribution of reflection is affected by season, city morphology, and building characteristics . Obtaining the time and location of sunlight reflection within a street environment is important to improve the comfort and safety of public spaces. This paper proposes a method to estimate the spatiotemporal distribution of sunlight reflection within a street based on street-view data. First, the solar path on the panorama is plotted to obtain the potential orientation of the radiation source and the reflection on building facades. Next, the continuous time–date distribution of direct and reflected sunlight at a certain site is obtained by the panoramic projection transformation approach. The accumulative duration and time-series parameters of the reflected scenario are estimated by a matrix operation. By mapping the time-specific duration of the sunlight reflection scene, we can obtain the spatiotemporal distribution within the street network. We applied the proposed method to a case study in a high-rise business district and quantified the range, duration, and intensity of reflected sunlight in the surrounding area. Seasonal changes, city morphology, and facade orientation were found to be the factors affecting the distribution tendency of reflected sunlight. The risk detection, visualization, and quantification analysis results on sunlight reflection can provide a reference for city management, urban planning, and environmental evaluation.