Development and validation of a reduced chemical kinetic mechanism for CFD simulation of combustion in a GCH4/GO2 combustor

For better understanding the combustion in rocket combustion chambers, employment of numerical simulation helps to predict important parameters: Temperature, Pressure, Flame speed, Heat flux, Ignition delay time, etc. Detailed mechanisms usually require large amount of computer resource and time. In this study, a 56-step, 22-species reduced skeletal mechanism is derived from GRI-Mech 3.0 under the specification of operating temperature, pressure and mixture ratio. Reduced mechanism is obtained systematically using the method of reaction path analysis and reaction rate sensitivity analysis. This mechanism is validated against experiments according to its prediction performance in ignition delay time and premixed laminar flame speed. Around operating pressure 20 bar in laminar flame speed validation, the skeletal mechanism delivers very good prediction accuracy against experimental measurements. This mechanism is also imported into numerical simulation, and predicts temperature in good agreement with experiments.