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

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

A qualitative investigation on double-skin façade fires

Fire hazard of the green architectural feature double-skin façade is always a concern. A hazard scenario with a room fire adjacent to the façade was identified earlier after interviewing with fire professionals. Experimental studies on the consequence of the fire hazard due to trapping heat and mass in the façade cavity carried out before will be reported in this presentation. The rig was of height 15 m with a fire chamber placed next to it. Flashover was induced to direct hot flame and smoke out. Only part of the building was studied instead of a full height façade due to resource limitations. Air temperature next to the upper interior glass pane was confirmed to be higher than the air temperature next to the exterior pane with normal air cavity depth in double-skin façades. Flame will then be diverted to the interior glass pane, giving possibility to spread fire to the upper rooms