An optimized core mechanism for H2/CO combustion in mild-like conditions

In this work, the H2/CO core of the widely used Aramco 2.0 mechanism was optimized for improve performances in diluted conditions. The resulting model showed accurate agreement with a wide set of experimental data regarding hydrogen, carbon monoxide and syngas ignition delay time in RCM and ST. Comparison with the nominal mechanism and another optimized mechanism for the same fuels is given. The uncertain variables selection was performed using a two-step sensitivity analysis which links all the mechanism parameters of the most impactful reactions directly with the quantity of interest (QoI). This methodology coupled with an Evolutionary algorithm for global optima searching was found to be particularly effective. Finally, the impact of the core optimization on the ignition delay time of low alkanes and alkenes was tested, showing promising results and room for future work.