Abstract
The progress of heat island effect and pollution by traffic emissions in urban streets has been serious problems. To avoid more serious situations and create more comfortable outdoor environment, the analysis on the influence of building and urban configurations has been required. As one of the building configurations which have large impact on above and inside urban street canyons, the influence of various roof shapes was investigated experimentally and numerically. But although many different combinations of roofs have been studied, the impact of the slope of slanted roofs on flow and dispersion has not been investigated systematically yet. Also, the influence of roof shape on urban ventilation has not been analyzed yet. The objective of this study is to investigate the influence of roof slope on (1) flow and dispersion inside the street canyon and (2) urban ventilation using LES (Large Eddy Simulation). The vortex structures of the cases which have peculiar flowfields were analyzed by POD analysis using LES results.
