Stabilization mechanisms of CH4 premixed swirled flame enriched with a non-premixed hydrogen injection

High-fidelity Large Eddy Simulations (LES) are performed to study the effect of hydrogen injection on a lean turbulent CH4/Air premixed flame. An Analytically Reduced Chemistry (ARC) mechanism is used achieve detailed description CH4/Air-H2 chemistry. First, validation this kinetic scheme against GRI-Mech 3.0 presented considering both simplified and complex transport properties. When added mixture, large variations mixture Prandtl N2 Schmidt numbers observed depending local species concentrations, features that missed by models. LES then applied structure stabilization mechanisms (? = 0.8) swirled flame enriched with using different modeling strategies. fully case considered results found validate approach. In agreement experiments, classical V-shape stabilized in low-velocity region near holder created central recirculation zone (CRZ). Then, enrichment achieved injecting 2% CH4 thermal power fuel lance. Both diffusion branches present case, impacting angle. The root main kernel injected reacting oxygen excess stream. Moreover, H2 consumed remaining burnt gases leads formation second branch inside CRZ which responsible an increase Given high concentration hydrogen, impact molecular models lift-off height highlighting importance properties any involving combustion.