NUMERICAL-SIMULATION OF FUME CUPBOARD PERFORMANCE

Calculated distributions of velocity and concentration of a passive sc alar for a modern fume cupboard arrangement are shown to be in close a greement with measurements, to quantify the nature of the flow more fu lly and to demonstrate the consequences of changes in the geometrical and flow boundary conditions. In particular, it is shown that the arra ngement of the sash has important consequences for the location of the main longitudinal vortex behind it and that the effect of removing th e 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 a ssociated with numerical and turbulence assumptions are discussed.