Molecular dynamics simulation of the inhibition effects of inert gases (Ar/He/N₂) on hydrogen oxidation

<p>In this paper, the inhibition effects of Ar/He/N₂ on the H₂-O₂ system near the extended second explosion limit were investigated by ReaxFF simulations. It was found that all three inert gases can inhibit the reactions, delaying the initiation reaction, and prolonging ignition delay since the generation and consumption of free radicals such as HO₂ and OH were suppressed. Further, the inhibitory effect has the correlation of Ar > He > N₂. The inhibitory effect of Ar is more pronounced compared to He due to the bigger effective radius and physical mass. Moreover, the addition of N₂ introduced extra initiation reaction (H₂ + N₂ → NNH + H) and generated additional intermediate products such as NNH and N₂OH, which result in the weakest inhibitory effect. Compared to diatomic inhibitors (e.g., N₂), the monatomic inhibitors such as Ar and He exhibit stronger inhibitory effects on the hydroxide reaction under high pressure.</p>