This research evaluated the ability of three types of models commonly used in fire investigations to predict characteristics of the fire environment produced from gas burners and single upholstered furniture items.
The models used represent the three categories of models identified in NFPA 921, Guide for Fire and Explosion Investigations: 1) Fire Dynamics Tools (FDT), a collection of specialized fire dynamics routines; 2) Consolidated Model of Fire and Smoke Transport (CFAST), a zone model; and 3) Fire Dynamics Simulator (FDS), a computational fluid dynamics model. These three models are maintained with ongoing verification and validation conducted by the National Institute of Standards and Technology with the support of the Nuclear Regulatory Commission. A quantitative analysis of the accuracy of predicting plume and compartment temperatures, flow velocities, flame heights, heat fluxes, oxygen concentrations, and additional measurands was provided for each model. This study provides guidance and insight on the uncertainty bounds that should be considered when using heat release rate (HRR) and fire environment data as input for a fire dynamics analysis that shows how uncertainties in the data propagate through the models. The reports, time histories of the data, and the data analysis from this study provide foundational documentation for an improved understanding of the repeatability of HRR data and thermal environment measurements for both a free-burn and compartment setting. This information can provide guidance that enables better choices for using the data in the analysis of a fire event. 2 figures, 2 tables, and a list of project products