Ignition kinetics of nitrocyclohexane behind reflected shock waves in inert and air environments

Nitrocyclohexane is an important propellant within the class of nitroalkane based energetic fuels characterized by the nitro functional group. Although several studies were reported on the ignition of small nitroalkanes, very few kinetic studies are performed on their ignition characteristics under oxygen-free conditions. Herein, the ignition kinetics of nitrocyclohexane in inert and air environments are studied using a high-pressure shock tube facility. The experiments are performed at pressure of 2, 5, 10, and 20 bar with equivalence ratios of 0.5, 1.0 and 2.0 under the temperature range from 950 K to 1420 K. The effect from fuel concentrations at 0.61%, 1.14% and 2.05% with nitrogen as the inert gas are also studied. Comparisons of the ignition kinetics with other fuels including nitromethane, 1-nitropropane, methylcyclohexane, and cyclohexylamine are performed. The present manuscript provides the first experimental data for nitroalkanes in inert conditions, and should be valuable to understand the combustion chemistry of nitroalkanes.