Computational simulation of worker exposure using a particle trajectory method.
The velocity field downstream of a worker is approximated with a discrete vortex algorithm. This information is used to calculate trajectories of massless tracer 'particles' released from a point-source of contaminant. Concentrations in the plane of this source are estimated by averaging over a number of such trajectories. Approximations include: (1) representing the worker by a two-dimensional elliptical cylinder; and (2) representing tracer gas contaminant by massless particles generated without momentum. These particles are transported by both vortex shedding and turbulent diffusion. Computer-predicted mean concentrations in the near-wake region downstream of the worker compare well with results from wind-tunnel tracer gas experiments employing a mannequin. Subsequently, the concept of a computational breathing zone is introduced, and predictions of worker exposure are made. These simulations of time-integrated breathing zone concentration also compare well with measured values.
Flynn
M R
MR
Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill 27599-7400, USA.
Chen
M M
MM
Kim
T
T
Muthedath
P
P
D000392:Air Movements; D003198:Computer Simulation; D006801:Humans; D008962:Models, Theoretical; D016273:Occupational Exposure