A numerical study of fire spread phenomena for multi-level apartment complexes

High rise apartment fires are perhaps the most dangerous residential fires. Within high rise buildings, flames and smoke can travel through ductwork, between interior walls, and up elevator shafts and stairwells. One of the fastest ways a fire spreads to other floors is along the exterior of the building due to open windows. Flame spread up vertical walls has been studied experimentally and computationally for years in the U.S. and abroad. Preventing or reducing fire spread on the exterior of buildings allows fire fighters more time to evacuate the occupants above the fire, and more time to control the fire from spreading to other floors or neighboring buildings. A numerical study has been undertaken to examine the reduction of vertical flame spread due to the presence of a balcony. The Fire Dynamics Simulator (FDS) code developed at the National Institute of Standards and Technology will be used to determine how balconies affect the vertical movement of fire. The FDS large eddy simulation methodology coupled with a mixture fraction combustion model will be tested. Implementing building geometry from scaled experiments, the computational study will vary balcony depth and geometry, in an effort to find an optimum balcony depth and configuration that significantly impedes vertical fire spread on the external wall. Wind impinging on the facade of the building will be introduced at various angles to determine what affect wind may have on fire spread in high rise buildings