The transient phenomena of methane catalytic ignition assisted by hydrogen pre-reaction

This paper investigates the transient characteristics of hydrogen-assisted methane-air catalytic combustion by both experiments and numerical calculations. The ignition criterion curve and the interested phenomena of hydrogen-assisted methane catalytic ignition are obtained in this study. With H₂ pre-reaction, the minimum CH₄ concentration required for successful ignition decreases with the increasing content of H₂. And based on the ignition delay time calculation in the catalyst channel and transient temperature measurements of surface and outlet gas phase, four ignition modes are revealed with three ignition regions as functions of hydrogen and methane volume concentrations along the ignition criterion curve. The evolution of hydrogen-assisted catalytic ignition of methane is dominated by the competition between surface and gas phase reaction and the abrupt increase temperature the ignition process.