EFFECT OF THE LOCATION OF THE EXHAUST DUCT, AN EXTERIOR OBSTRUCTION AND HANDLE ON THE AIR-FLOW INSIDE AND AROUND A FUME CUPBOARD

In order to be able to reduce the leakage of contaminant out of a fume cupboard it is first necessary to investigate the detailed fluid flow patterns inside and around the fume cupboard. Because of the difficul ties and expense of performing these experiments, in this paper a comp utational fluid dynamics approach has been used. The aim of the work i s to investigate the potential of various factors which cause the leak age of contaminant from the fume cupboard. In particular the effect of : (i) the location of the exhaust outlet on the roof of the fume cupbo ard; (ii) exterior obstructions of different shapes and sizes in front of the fume cupboard; and (iii) the fume cupboard handle, which takes various shapes and positions, in laminar and turbulent fluid flow bot h inside and around the fume cupboard. From the fluid hows observed, f or each configuration, their importance in relation to future experime ntal work to be performed and possible new designs of fume cupboards i s discussed. Wherever possible comparisons have been made with existin g experimental data and in all cases good qualitative agreement is ava ilable. Copyright (C) 1996 British Occupational Hygiene Society.