Comparative assessment of CFD Tools and the Eurocode Methodology in describing Externally Venting Flames

Abstract

The ability of currently available Computational Fluid Dynamics (CFD) tools to adequatelydescribe Externally Venting Flames (EVF) is assessed, aiming to demonstrate compliance withperformance-based fire safety regulations. The Fire Dynamics Simulator (FDS) CFD tool is used tosimulate the EVF characteristics in a corridor-compartment-façade configuration exposed to natural fireconditions. Numerical results of the temporal evolution of gas velocity, gas temperatures and flame shapeare obtained for both the interior and the exterior of the compartment. Predictions are compared to respectiveexperimental data, as well as to correlations suggested by the Eurocode methodology. The effects ofventilation conditions are investigated by simulating both Forced Draught (FD) and No Forced Draught(NoFD) test cases. The obtained results suggest that currently available CFD tools are capable of achievinggood qualitative agreement with experimental data and, in certain cases (e.g. FD conditions), adequatequantitative agreement, that generally outperforms the Eurocode prescriptive methodology.