PRELIMINARY STUDIES ON MECHANICAL SMOKE EXHAUSTS IN LARGE SPACE BUILDING FIRES

An analysis of the requirements for mechanical smoke exhaust in large space buildings was made and some experiments in a fire test atrium have been performed. It can be concluded that the temperature of smoke in large space building fire is usually quite low which makes them easy to descend and to mix with air. Usually it’s difficult to control the descending of a smoke layer effectively when there is a fire source. Mechanical smoke exhaust is an exchange process of smoke and air. It clears smoke away mostly by dilution. The influence of fans to disturb flow fields and the location of air supply openings should also be taken into account