Wind tunnel measurements of cross-ventilation flow in a realistic building geometry: Influence of building partitions and wind direction
Mutmainnah Sudirman, Stefanie Gillmeier, T. van Hooff, Bert Blocken
Abstract
Wind tunnel measurements have widely been used for validation of computational fluid dynamics simulations of natural ventilation airflows. However, the majority of such measurements employed simple generic single-zone buildings, while there is a lack of studies on realistic buildings including flow-critical geometrical features (e.g. internal partitions). To assess the effect of internal partitions at different incident flow angles (α = 0° and α = 30°), wind tunnel measurements of velocities in and around a cross-ventilated realistic residential building (with and without internal partition) were performed. Measurements were conducted at a geometric scale 1:40, using laser Doppler anemometry. Results indicate a large impact of the internal partition on indoor airflow distribution and resulting ventilation flow rates. For instance, for α = 0°, on the partitioned building side, regions of velocity increase (from ∼0 m/s to ∼80% of the outdoor reference velocity, U ref ), but also regions of velocity decrease (from ∼50% of U ref to ∼0 m/s) were observed. The ventilation flow rate through the windows at the partitioned side decreased by 23% and 32%, respectively. For the partitioned building, a change from α = 0° to α = 30° resulted in regions of velocity increase from 0 m/s to ∼60% of U ref . • Wind tunnel tests on naturally cross-ventilated realistic buildings at scale 1:40. • Velocity field in and around the unpartitioned and partitioned building models. • Effects of indoor partition & wind direction were assessed on ventilation flow rates. • Results provide a database for the validation study under isothermal conditions.