A numerical investigation of impact of architectural and climatic parameters of windcatcher systems on induced ventilation

The large energy demand from the HVAC industry for residential buildings, along with the ever growing need for the utilization of renewable sources of energy, has brought considerable attention to the area of induced ventilation. Windcatchers are green architectural structures historically used for the passive ventilation of the indoor spaces with the minimal non-renewable energy consumption. In this paper, a computational fluid dynamics (CFD) model is used to assess a windcatcher's performance with different characteristics of the windcatcher design. For a single room with heat emitting objects, the effects of the windcatcher louver design and height were thoroughly evaluated in conjunction with a variety of dominant wind velocity and incident angles. A comparison was drawn between the ventilation efficiency for the cases of circular and rectangular windcatcher designs. Thermal discomfort (PD) values due to draft were calculated for different temperature and wind velocities. The developed model was employed to obtain the optimized configuration for the windcatcher-room system. The effect of ambient weather conditions on the results was investigated by performing the simulations for a range of air temperature and velocities. Results obtained in this paper provide windcatcher designers with valuable insights on the important design parameters such as windcatcher height, louver design and impact of ambient conditions.