Modelling of Mitigation of Vapour Cloud Explosions Using Flame Inhibitors

Abstract

The consequences of vapour cloud explosions can be devastating causing numerous fatalities and destruction of large parts of industrial facilities. Recently a technique was suggested to mitigate vapour cloud explosions using flame inhibitors. Flame inhibitors would be injected into the vapour cloud upon gas detection. In case of ignition of the vapour cloud the flame inhibitors assure a considerable reduction of the combustion rates thus also reducing the pressures and drag loads generated by vapour cloud explosions. Experimental results confirm the feasibility of the principle of using flame inhibitors for mitigation of vapour cloud explosions. To design systems for deployment of flame inhibitor clouds in a congested petrochemical facility assuring a considerable reduction of the explosion loads due to vapour cloud explosions it was suggested to use the dedicated CFD-model FLACS. To allow for this the combustion model was extended allowing for describing the effect of flame inhibitors on combustion and a model describing particle laden flow was implemented. The present paper presents the development of the extended combustion model and other models to represent the influence of flame inhibitors on combustion and particle laden flow, and its validation.