Suppression effects of typical inert gases on the explosion characteristics of gasoline mist in closed vessel

Gasoline presents considerable safety hazards during the storage and transporta?tion processes. In the study, the effects of three typical inert gases of CO2, N2, and Ar on the cloud explosion of gasoline were studied using a 20 L spherical explosion vessel. The experimental results showed that the ultimate volume fractions, nU, of the inert gases required to completely suppress gasoline cloud explosion were 86 vol.%, 88 vol.%, and 92 vol.%, respectively. As the volume fraction, n, of inert gases increased, the maximum explosion pressure, ?Pmax, the maximum explosion pressure rise rate, (dP/dt)max, the maximum average temperature, Tam, and the explosion risk index, KG, of the gasoline cloud explosion all exhibited a downward trend, while the combustion duration, td, increased. The CO2 primarily inhibited the initial stage of the gasoline cloud explosion reaction, reducing the oxidation rate by interfering with elementary reactions through both physical (heat absorption) and chemical (reaction inhibition) ways. While N2 and Ar mainly weakened the second stage of explosion, primarily through heat absorption and dilution effects. The research conclusions could offer theoretical guidance for the safe storage and transportation of gasoline by making explosion protection measures.