Assessing wind comfort in urban planning

There are increasing concerns regarding the quality of urban public spaces. Wind is one important environmental factor that influences pedestrians' comfort and safety. In modern cities there are increasing numbers of high constructions and complex forms which can involve problems of significant wind discomfort around these buildings. Architects and town planners need guidelines and simple design tools to take account of wind in their projects. This paper reports the progress made in using computational fluid dynamics (CFD) simulations for assessing wind comfort in urban planning. Fluent software was validated for wind studies in urban environments by comparing CFD simulation results with published wind-tunnel tests. This validation shows that mean wind velocities around buildings can be simulated numerically with a very high degree of accuracy. On the basis of the results of a large number of CFD simulations, a methodology and simple graphical tools were developed to quantify critical wind speeds around buildings. In practice these should help architects and town planners when designing our built environment. Moreover, this study shows how numerical modelling is now a high-performance tool for developing useful guidelines and simple design tools for urban planners.