How the Position of a Root-Top One-Sided Wind Tower Affects Its Cross-Ventilation Effectiveness

Despite their antiquity, wind towers have only recently gained popularity among the researchers and architects practicing natural ventilation, especially since their performance relies both on wind and stack effect. In studying natural ventilation using wind towers, different environmental parameters and their various geometrical elements have been taken into consideration previously, but the position of the wind tower with respect to the lower building has never been assessed. Therefore, this study employs CFD to understand how at various wind incident angles, three different positions of a one-sided wind tower with respect to the lower room’s window can provide different cross-ventilation efficiencies in terms of mass flow rate, velocity magnitude, and mean age of air inside the room. Furthermore, this study shows how a case with a better airflow rate might not necessarily have the freshest air at the same time. Therefore, for a natural ventilation study to be reliable, it is necessary to evaluate several parameters simultaneously.