Abstract
To promote ventilation in the street canyon is one of the effective urban heat island measures. The analysis on the relationship between properties of urban block and wind environment in the street canyon is required. In this study, relationship between wind environment in the street canyon and characteristics of urban block e.g. building cover ratio, variation of building heights, as well as roadside properties e.g. direction of street, width of street, height of building, is studied by CFD simulation results carried out in the central Osaka city. Ventilation in the street canyon is promoted by positive and negative pressure areas which are formed by variation of building heights. Both "the vertical wind path" caused by high-rise building and "the horizontal wind path" formed along the wide road parallel to upper wind direction should be considered for the improvement of ventilation in the street canyon. It is also confirmed that the attention to windward and downwind areas should be noted.
