On characteristics of flow around building models with a view to simulating the minimum fraction of the natural boundary layer

The results of an investigation of the characteristics of the flow around building models in terms of the various stagnation points are reported. The influence of the mean velocity profile, turbulence intensity, percentage boundary layer immersion ratio and the building model's aspect ratio on the location of the various stagnation points was studied from the point of view of simulating the minimum fraction of the atmospheric boundary layer in a wind tunnel for building aerodynamics investigations. It is suggested that the atmospheric boundary layer height of at least two to three times the building height should be simulated in a wind tunnel for studying the effects of strong and gusty winds on buildings and structures.