Development and application of a dynamic flame extinction and re-ignition model in FDSMaragkos, Georgios (Korespondenčni avtor) Floyd, Jason (Avtor) Lucherini, Andrea (Avtor) Snegirev, Alexander (Avtor) Igweh, Elijah Jerome (Avtor) Merci, Bart (Avtor) flame extinctionflame re-ignitioncritical flame temperaturestrain rateCFD modellingFDSA new dynamic flame extinction and re-ignition model that considers the local properties of the flow has been developed. The extinction model is based on the default enthalpy balance used by the Fire Dynamics Simulator (FDS) and employs a dynamic calculation of the critical flame temperature, T CFT, derived from well-stirred reactor simulations with different diluent concentrations, which depends on the local mixing time and species concentrations. On the other hand, re-ignition is allowed to occur if the cell temperature is above a threshold re-ignition temperature, T ign, derived from counterflow simulations considering hot fuel and oxidizers, which depends on the local strain rate magnitude. The model has been implemented in FDS and validated against two well-characterized scenarios with different fuels (i.e., UMD line burner and FM burner cases) involving flame extinction due to dilution. Overall, improved predictions with respect to the reduction of the combustion efficiency, when compared to the original extinction and re-ignition model of FDS, are obtained. The predicted T CFT and T ign were (significantly) higher and lower, respectively, compared to the default value of FDS. In addition, lower O2 concentrations were qualitatively observed within the flame region with the new model.Elsevier20262026-07-23 06:40:49Neznano31241UDK: 614.84ISSN pri članku: 1873-7226DOI: 10.1016/j.firesaf.2026.104927COBISS_ID: 285621507sl