Air Flow through the Door Opening Induced by a Room Fire under Different Ventilation Factors

Air flow through the door opening induced by a room fire was studied by Computational Fluid Dynamics (CFD) model Fire Dynamics Simulator (FDS) version 5 in this paper. There are two key problems in applying CFD. The first one is on design fire boundaries, and the second one the computing grid size. Consequently, many arguments were raised in fire hazard assessment for projects applying performance-based design in providing fire safe design. Prescribed input heating rate based on the experimental results was used in FDS. Three fire scenarios based on different ventilation conditions were simulated. Different boundary conditions were investigated to evaluate free open boundary conditions in applying CFD to predict heat release rate (HRR) and the air flow through the opening. The effects of open boundary conditions on HRR and pressure distribution at the opening plan under different ventilation factors were analyzed.