This Digest explains the methodologies being used for the computer simulation of fire. It focuses on models of the fire itself: the essentially gas phase phenomenon at the heart of any fire simulation.
Numerical modelling has become increasingly attractive for those wishing to fully exploit the freedoms to achieve safe, cost effective design offered by performance based regulation.
This new edition of Digest 367 supersedes the version published in 1991. It explains fire growth and spread, and the two basic types of computer simulation methodologies. These are the zonal models, and the more universal field models that use the specialist discipline of computational fluid dynamics. Two types of field model are described which employ alternative approaches using Reynolds Averaged and Large Eddy methodologies to capture the influences of turbulence. An example shows the BRE CRISP model applied to the problem of smoke spread through a two storey theatre and the evacuation of the occupants. 8 pages.