Citation

Allen G. IMSA J. 2003; 41(2): 3 p..

Copyright

(Copyright © 2003, International Municipal Signal Association)

DOI

unavailable

PMID

unavailable

Abstract

A computer simulation using computational fluid dynamics helped adjust the design of a rapid transit station after the fire department expressed concern that the ventilation system relied too heavily upon buoyancy to vent smoke. The simulation showed that buoyancy was not sufficient under all conditions, so different configurations using fans in the vents were tested. Testing and simulation identified the method that would remove the most smoke using the fewest fans, in addition to a clear margin of safety. A second simulation using computational fluid dynamics showed the smoke would be vented while leaving evacuation routes clear. Another analysis was carried out at the fire department's request to take into account other variables, such as wind blowing into the escape vents and a series of smaller fires, which do not produce the large amount of heat that can create buoyancy. The additional simulation identified problems in the event of these occurrences, and the design was amended to include additional fans and other design changes that satisfied the fire department's concerns.