An analysis of compartment fire doorway flows

A mathematical study is made to compute the doorway flow behavior due to fire in a room. Two approaches were taken, first a model attempting to include the effect of fire entrainment and vent mixing; second was a model based on an ideal point source plume fire—both in the zone model concept. Limiting analytic results were found for the latter to give insight into the physics. The results were compared to available flow data, and an approximate formula was developed to predict the doorway mass flow rate to within 20% for a wide range of fire conditions. CFD computations were also explored using FDS. Results are compared from FDS and the zone model with experimental data for a wide range of variables.