Indoor air quality depends on the concentration and distribution of ai
rborne contaminants. Often these are not uniform throughout the enviro
nment because the inlet air may not mix completely with the room air t
o dilute contaminants, which can be the result of poor room design or
nonequilibrium conditions. The structure of the airflow and the extent
of contaminant mixing depends on the location of flow and contaminant
sources and sinks, as well as on the geometric barriers in the room.
This paper describes a three-dimensional numerical simulation of the t
ransport and dispersion of a passive, airborne contaminant in which th
e Navier-Stokes and concentration equations are solved under transient
conditions for a rectangular enclosure with a single ventilation inle
t and outlet. This investigation focuses on the effects of flow obstru
ctions and ventilation rates on contaminant mixing.