Effect of initial conditions on the inhibition process of H$_{\textrm{2}}$–O$_{\textrm{2}}$/air detonations using CF$_{\textrm{3}}$I, CO$_{\textrm{2}}$, and H$_{\textrm{2}}$O

Abstract

The unwarranted leakage/release of hydrogen gas from metal processing, automotive, petrochemical industries, and nuclear reactors, along with its subsequent ignition and transition to detonation, could lead to catastrophic damage to both life and property. The development of practical hazard prevention and safety control systems demands an understanding of the effectiveness of the chemical inhibitors to suppress/mitigate a detonation wave under varying operational conditions. In the current study, the inhibition efficiency of chemical inhibitors under varying mixture initial conditions was investigated using numerical computations. The inhibition efficiency of trifluoroiodomethane (CF$_{\textrm{3}}$I), carbon dioxide (CO$_{\textrm{2}})$, and steam (H$_{\textrm{2}}$O) on hydrogen-oxygen/air mixtures was evaluated using a detailed chemical kinetic model for hydrogen oxidation. ZND computations were carried out over a range of initial mixture composition, pressure, and temperature. It was found that CF$_{\textrm{3}}$I is a better inhibitor than CO$_{\textrm{2}}$ and H$_{\textrm{2}}$O at all the initial mixture conditions. However, at very high temperatures, the inhibitors CF$_{\textrm{3}}$I, CO$_{\textrm{2}}$, and H$_{\textrm{2}}$O have a similar detonation inhibition efficiency. The inhibition efficiency of carbon dioxide and steam is comparable and significantly lower than CF$_{\textrm{3}}$I. The findings from the current work can be used to design optimized detonation safety systems over a range of practical operating conditions.