NUMERICAL-SIMULATION OF FUME CUPBOARD PERFORMANCE

Calculated distributions of velocity and concentration of a passive scalar for a modern fume cupboard arrangement are shown to be in close agreement with measurements, to quantify the nature of the flow more fully and to demonstrate the consequences of changes in the geometrical and flow boundary conditions. In particular, it is shown that the arrangement of the sash has important consequences for the location of the main longitudinal vortex behind it and that the effect of removing the rear baffle results in the creation of two conical vortices that are scavenged through the top outlet. The calculation method is based on the numerical solution of time-averaged equations; the uncertainties associated with numerical and turbulence assumptions are discussed.