FSEM: An approach to model contribution of synergistic effect of fires for domino effects

Fires are major primary events in domino effects in chemical and process industries, and released thermal radiation is a main cause of accident propagation. In fire-induced domino effects, synergistic effect of multiple burning units will increase risk of domino effects, and the synergistic effect is time-dependent. In this study, a superimposition based new approach is proposed to model the contribution of synergistic effect of fires for domino effects, and a numerical solution of the approach is developed. In this approach, the synergistic effect of fires is modeled dynamically through time-variant target unit wall temperature and received thermal flux, and the receivable thermal dose is proposed as failure criterion and is modeled. The contributions of synergistic effect on the risk of domino effects are assessed by time to failure and escalation probability of target unit. The proposed approach is able to not only model the synergistic effect of fires, but also to understand the temporal evolution of synergistic effect when higher-level accidents occur. A case study demonstrates the effectiveness, advantages, extension of the proposed approach to model the contribution of synergistic effect for domino effects risk.