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

摘要

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 difficulties and expense of performing these experiments, in this paper a computational fluid dynamics approach has been used. The aim of the work is to investigate the potential of various factors which cause the leakage of contaminant from the fume cupboard. In particular the effect of: (ⅰ) the location of the exhaust outlet on the roof of the fume cupboard; (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 both inside and around the fume cupboard. From the fluid flows observed, for each configuration, their importance in relation to future experimental work to be performed and possible new designs of fume cupboards is discussed. Wherever possible comparisons have been made with existing experimental data and in all cases good qualitative agreement is available.