Mean age of air in a naturally ventilated office: Experimental data and simulations

Indoor air quality has an important role as health determinant; it relates to the health and comfort of building occupants.The present paper investigates the wind-forced natural ventilation rates of an office as observed with tracer decay, according to ISO 16000-8:2007 Standard, both with an experimental and numerical procedure; experimental data were used to validate the numerical method. Moreover the only infiltration rate case was analyzed.Natural ventilation was created by opening the window and the door of the office. A simulation model of the room was carried out by using the computational fluid dynamics (CFD) code Fluent. The experimental set up of the procedure was developed by a portable gas chromatograph. In both the numerical and experimental approach the mean age of air linking to ventilation efficiency was calculated. The defined experimental procedure can be applied to different situations, in order to evaluate the efficiency of both natural and forced ventilation existing systems. When the ventilation is due to the opening of the window and the door, the simulation results are in a good agreement with the experimental ones, therefore the model could be applied to different situations, in order to reduce costs and time in the evaluation of indoor air quality.

► Importance of indoor air quality in the characterization of discomfort for occupants sensitivity.
► Experimental and numerical study about air quality in a naturally ventilated office room.
► A measurement methodology (ISO 16000-8) was set up and the local mean age of air was calculated.
► The methodology could be applied for both natural and forced ventilation systems study.
► The numerical model is useful for the prediction of mean age of air, allowing costs and time reduction.