Fire Safety Science Digital Archive

Results of a series of tests on the deflagration of methane-air mixtures in a large vented enclosure are presented. Experiments were made in FM Global’s 63.7 m³ chamber. The chamber was 4.6 x 4.6 x 3.0 m with a vent opening on one side. Vent areas of either 2.7 or 5.4 m² were used. Tests were performed with ignition either at the center of the chamber or at the center of the wall opposite the vent. Methane-air mixtures with methane concentrations close to 9.5% vol. were used in the tests. Pressure data, as function of time, and flame time-of-arrival data were obtained both inside and outside the chamber near the vent. Detailed experimental data is used in the paper to test a three-dimensional gasdynamic model for the simulation of gaseous combustion in vented enclosures. The model is based on a Large Eddy Simulation (LES) solver created using the OpenFOAM CFD toolbox using sub-grid turbulence and flame wrinkling models. Results from the calculations are compared with the experimental data. The capabilities and deficiencies of the model are discussed.