Reevaluation of the reaction rate of H + O₂ (+M) = HO₂ (+M) at elevated pressures

The rate coefficients for H + O₂ (+M) = HO₂ (+M) at high-pressure conditions were re-evaluated using the reported experimental shock tube data of Davidson et al. (1996), Bates et al. (2001), Shao et al. (2019) and Choudhary et al. (2019), and based on an updated mechanism of Hong et al. (2011). The major updates of the Hong et al. Mechanism compared to the originally used GRI-Mech in the works of Davidson et al. (1996) and Bates et al. (2001) were the interfering reactions of H + O₂, H + HO₂ and OH + HO₂ as well as NO_x-related reactions. After applying the updates of the elementary reaction kinetics, the revised rates of H + O₂ (+M) = HO₂ (+M) for Davidson et al. (1996) and Bates et al. (2001) showed improved agreement with each other, and consequently led to a more reliable Troe formula of H + O₂ (+M) = HO₂ (+M) with M = Ar and N₂ covering the pressure range of 1–150 bar and temperature range of 300–1800 K. The new Troe formula is expected to facilitate kinetic model development and high-pressure combustion studies.