Analysis of sunshine duration and surface temperature of a building in urban areas using a sunshine duration model and measurements

This study analyzed the sunshine duration and building surface temperatures for various orientations (east, west, south, north, and roof) within a university campus. The sunshine duration was calculated using a sunshine model that determines sunshine presence based on solar azimuth and altitude angles, as well as building and topography data, performed at one-minute intervals. The performance of the sunshine model was validated using solar azimuth and altitude data provided by the Korea Astronomy and Space Science Institute (KASI) and field measurement data. The validation results demonstrated that the sunshine model used in this study is suitable for analyzing sunshine duration. Building surface temperatures for the east, west, south, north, and roof surfaces were measured using a thermal imaging camera. Measurements were taken hourly from 9 AM to 6 PM over two days. There was a close relationship between sunshine duration and building surface temperatures. The north-facing surface, which had the shortest sunshine exposure, showed the lowest surface temperature, while the roof, with the longest sunshine exposure, had the highest surface temperature (average surface temperature difference: approximately 11degree celsius). Furthermore, the time of the highest surface temperature varied according to the sunshine exposure time. The east-facing surface, which received sunshine primarily in the morning, peaked at 11 AM, while the west-facing surface, which received sunshine mainly in the afternoon, peaked at 3 PM.