Short-term dispersion of indoor aerosols : can it be assumed the room is well mixed ?

At a point-source release, point-wise concentrations may greatly exceed the well-mixed conditions. In order to examine this assumption, aerosols have been released in a test room with HEPA filter ventilation, at different conditions of room furnishings and different contaminant release locations. The aerosol concentrations were measured simultaneously, for each experiment, at seven locations by nephelmetry. CFD simulations were performed to provide details of the velocity and particle concentration profiles.The numerical results along with the experimental ones corroborated the hypothesis.