Fire Safety Science Digital Archive

The field modeling of compartment fires incorporates increasingly complex representations of the physical and chemical processes which may occur and these models, in turn, demand detailed evaluation. The influence of alternative descriptions of combustion in the fire source and the introduction of a ray tracing radiation model (discrete transfer) are assessed in this paper within the framework of progressively relined mesh geometry and by detailed comparison with the experimental measurements in the Steckler compartment fire. The predictions are made with SOFIE, a code specifically developed for building fire prediction. The reported comparisons demonstrate that detailed quantitative predictions of velocity and temperature fields can be performed accurately, given a satisfactory combination of grid resolution and physical modeling, particularly in relation to that of combustion and radiative exchange. Improved accuracy is shown to accompany the implementation of the discrete transfer radiation model, together with eddy break-up combustion, in comparison with the adoption of a more simply prescribed heat source. The introduction of a flamelet-based combustion model offers the additional prospect of incorporating more detailed chemistry, for example in relation to CO, into room fire prediction.