Predictability of Flashover by Zone Models

Two additional flashover inspection criteria were established from a recent study on identifying routes to chaos in a compartment fire. There, phase space diagrams on fire temperatures and their time rates of change were analyzed. The proposal was applied to study whether flashover can be predicted by a two-layer zone model. Two popular zone models ASET and CFAST were selected. Compartments of different sizes and fires with different heat release rates were considered. Transient values of the fire temperatures and their time derivatives were studied. It is concluded that in addition to the current flashover criteria based on gas temperature near to the ceiling, heat flux at the floor level and flames coming out of the openings, the rate of change of fire temperature should be inspected.