Numerical studies on heat release rate in a room fire burning wood and liquid fuel

Heat release rates of burning gasoline and wood fires in a room were studied by computational fluid dynamics (CFD). Version 5.5.3 of the software Fire Dynamics Simulator (FDS), which is the latest one available, was selected as the CFD simulation tool. Predicted results were compared with two sets of reported data from full-scale burning tests. In the two sets of experiments, the scenarios were set at gasoline pool fire and wood chipboard fire with gasoline respectively. The input heating rate of gasoline pool fire based on experimental measurements was used in the first set of experiments. Three scenarios G1, G2 and G3 with different grid systems were simulated by CFD. The grid system of scenario G2 gave more accurate prediction, which was then used to study the second set of experiments on wood chipboard with gasoline. The combustion model in FDS was used in wood chipboard fire induced by gasoline pool. The wood chipboard was allowed to burn by itself using the pyrolysis model in FDS. The effects of the boundary conditions on free openings for the same set of experiments were studied by three scenarios SOB1, SOB2 and SOB3. Boundary condition SOB2 gave more reliable prediction among the three boundary conditions. Two other scenarios on the effect of moisture content of wood were also studied. The predicted HRR curve was found to agree better with experiment in using SOB2.