Effects of Porosity on Wind Driven Natural Cross Ventilation of a Full Scale Building
Natural ventilation for thermal comfort to the occupants can be achieved if the buildings are designed in favor of the available wind direction and wind force. The replacement of any mechanical ventilation system not only saves the electric cost but also reduces the pollutants what are generated during the electricity production stage. The effects of porosity on the Wind Driven Natural (WDN) cross ventilation of a full scale building has been investigated using the Computational Fluid Dynamics (CFD) technique. The numerical methodology has been validated through a satisfactory comparison with an experimental work. The Renormalization Group k e (RNG) turbulence model has been applied to capture the turbulence accurately. The porosity effects have been completely analyzed and it is found that the efficiency (66%~74% of the ventilation system depends on porosity (1% to 30% whereas the maximum efficiency is obtained at 5% porosity. The ventilation phenomenon is found Reynolds number independent.