Appropriate evaluation of fire behavior during the fully-developed phase is important for assessing the risk of building collapse and fire spread to adjacent buildings. In this study, a series of model experiments was conducted to investigate the fire behavior in compartments with varying wood fuel loads. Under small opening conditions, the increase in the wood fuel load had no notable effect on the heat release rate (HRR), but increased the fire duration and gas temperature. In certain cases, wood surface combustion continued even after flame ejection from the opening had ended, which maintained a high gas temperature for a long time. Under large opening conditions, the increase in wood fuel load had no notable effect on the fire duration, but increased the HRR and the gas temperature. The gas temperature measured by experiment was analyzed using the extended McCaffrey–Quintiere–Harkleroad (MQH) model. In the original MQH model, the effect of heat loss to the compartment surfaces on the gas temperature was considered as the main mechanism of heat loss. The extended model additionally considered the effects of the radiative heat loss through the opening and the change in burning mode between ventilation-controlled and fuel-controlled fires. For fuel-controlled fires, the effect of fuel surface area on compartment gas temperature was explicitly considered. The results of regression of the experimental data indicated that the power index obtained for the term for heat loss to the compartment surfaces of the extended model was equivalent to that of the original model in both the ventilation-controlled and fuel-controlled fire conditions. However, the newly considered effect of radiative heat loss through openings was minor in the ventilation-controlled fire condition.

Creative Commons License

Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.