Natural ventilation design for low-rise buildings: comparison between a nodal model and wind tunnel tests

The aim of this study is to check the accuracy of a nodal model to predict correctly the flow fields involved inside a building by wind-induced pressure. The model is confronted to experimental tests involving a four-storey dwelling at a reduced scale of 1/20 placed in a wind tunnel facility. Different configurations are tested considering openings of different sizes for outside openings as well as for internal doors and the presence or not of a collective duct connecting the kitchens to the outside at roof level. For each configuration, various wind incidences are studied. Internal pressure coefficient obtained in each room is compared between the experiment and the model. The effects of the variation of the windows discharge coefficient as function of wind incidence is discussed.