Non-buoyant pollutant sources and particles in displacement ventilation

Particle transportation and ventilation efficiency, with non-buoyant pollutant sources, in a displacement-ventilated room were evaluated. A resuspension of floor deposited particles caused by the influence of the supply air or people moving around may increase the number of particles in the convection flows. Particle concentrations at different positions under steady state and transient conditions were measured. The results indicate that there seem to be little risk of resuspension of particles, in the measured size interval, by the influence of the supply air. With a forced resuspension the particle concentrations in the convection flows differ from the concentration outside the convection flow. The contaminant removal effectiveness was much dependent on the position of the pollutant sources.