The effects of external wind pressure distributions on wind-induced air motion inside buildings

Wind pressure distributions on external surfaces of buildings have been used in the past for predicting wind loading on structures and cladding, air infiltration rates, and more recently, volumetric air flow rates through large openings such as windows. This paper presents a new application for wind pressure data. The purpose of this study was to assess to what extent surface pressure data measured on sealed building models could be used to predict wind-induced indoor air velocities in buildings with open windows. This indoor air motion could then be used to predict the thermal comfort to be expected in a naturally ventilated building. The study was accomplished by conducting two sets of tests in a boundary layer wind tunnel. In the first, indoor air velocity and turbulence intensity distributions were measured in models with openings for various wind directions and building configurations. In the second, the external surface pressure distribution was measured on sealed models of the same building configurations. Empirical correlations were then developed to relate indoor air motion parameters (velocities and turbulence intensities) to the external surface pressure distributions. These correlations, based on over 200 tests, can predict indoor air motion with a good level of accuracy as a function of wind direction and the external pressure distribution measured on sealed models.