To accurately estimate the natural ventilation of outdoor spaces surrounded by low-rise buildings using a wind tunnel requires correct representation of the natural wind regime combined with appropriately scaled building models and testing method. Existing outdoor ventilation studies are largely based on wind speed and estimated air change rates. Wind speeds mainly influence: peoples comfort, safety in pedestrian areas, the heat transfer between outdoor surfaces and airflow, and evaporation from wet surfaces.
To accurately estimate the natural wind driven ventilation potential of a specific low rise building in a densely shielded or built-up area under local wind conditions, it is necessary to have site wind frequency data, pressure coefficient data, details about the windward and leeward openings of the building and the data related to building design. This paper summarises the appropriate data and discusses how to obtain these in order to estimate the natural cross ventilation potential of such a low-rise building.