NUMERICAL-SIMULATION AND EXPERIMENT ON THE TRANSPORT OF FINE PARTICLES IN A VENTILATED ROOM

The change in concentration distribution of particulate contaminants e mitted in a room was studied experimentally and theoretically to inves tigate whether the transport of contaminants in a room with a source o f particles can be predicted by numerical simulation, Tracer contamina nts, monodisperse fates particles, were introduced into a 3.3 m x 2,7 m x 2 m room with clean air for a given time, and the change in the co ntaminant concentrations with time was measured at various positions i n the room, Calculations of the spatial and temporal distributions in the gas velocity and contaminant concentration were performed to predi ct the concentration change, with the Navier-Stokes and convection-dif fusion equations solved numerically. The experimental results showed t hat the concentration distribution depends on the position of introduc tion of the contaminants. It was also indicated that the contaminants introduced near the room floor diffuse more than predicted, However, t he calculated concentrations agreed almost quantitatively with the mea sured results, except near the floor and walls. The change in the conc entration with time and the dependence of the concentration distributi on on the position of the particle source were well reproduced by the calculation.