Spherically Expanding Flame Simulations in Cantera Using a Lagrangian Formulation

A Lagrangian-based one-dimensional approach has been developed using Cantera to study the dynamics of spherically expanding flames. The detailed reaction model USC-Mech II has been employed to examine flame propagating in hydrogen-air mixtures. In the first part, our approach has been validated against laminar flame speed and Markstein number data from the literature. It was shown that the laminar flame speed was predicted within 5% on average but that discrepancies were observed for the Markstein number, especially for rich mixtures. In the second part, a detailed analysis of the thermo-chemical dynamics along the path of Lagrangian particles propagating in stretched flames was performed. For mixtures with negative Markstein lengths, it was found that, at high stretch rates, the mixture entering the reaction-dominated period is less lean with respect to the initial mixture than at low stretch rate. This induces a faster rate of chemical heat release and of active radical production which results in a higher flame propagation speed. Opposite effects were observed for mixtures with positive Markstein lengths, for which slower flame propagation was observed at high stretch rates compared to low stretch rates."