Numerical analysis for natural ventilation of a room

Depending on the social development, the indoor comfort conditions are increasing. The indoor comfort is obtained either by an air conditioning system or natural ventilation. Initial and operational cost of an air conditioning system constitutes a considerable amount of investment. Hence, in recent years, the natural ventilation has been emerging as an important alternative system for ventilation of indoors. In this study, natural ventilation of a room is numerically analysed. The airflow, temperature distribution and concentration distribution of carbon dioxide in the air were numerically simulated with different window locations and wind speed (0, 1,0 and 1,5 m/s). The time depended continuity, momentum, energy and concentration equations of the problem were solved using FLUENT software package. The turbulence was modelled using realizable k- ? turbulence model. The buoyancy effect was modelled considering the full effect of the density variation due to temperature distribution. Simulations were performed for the natural ventilation in summer and winter conditions. From the results of the simulations in summer conditions, the heat removal rate from the room during a cool period of the day was determined. From the results of the simulations in winter conditions, the time needed to remove the polluted air from the room was determined. The simulations showed that the time needed for removal of the polluted air from the room depends on the window locations and wind speed. For the room considered in this study, it was observed that in the first 60 seconds of the ventilation, carbon dioxide concentration 90% decreases.