Effects of Differential Diffusion on the Stabilization of Unsteady Lean Premixed Flames Behind a Bluff-Body

摘要: Two-dimensional direct numerical simulations were conducted to investigate the effects of differential diffusion on flame stabilization and blow-off dynamics lean premixed hydrogen–air syngas–air flames stabilized a meso-scale bluff-body in square channel. The unity Lewis number for all species was imposed isolate diffusion. Four sets simulation cases conducted. Two different inflow temperature with applied examine distinct levels hydrodynamic instability. Each case compared non-unity how affects overall responses, instabilities, mechanism. For cases, observed several modes as velocity approaches limit. One primary an increased level instability due lower thus density ratio. gas also led weakening re-ignition quenched local mixture by product entrainment. combined manifested suppression events, leading revised conclusion that ultimate behavior at high conditions are mainly controlled onset extinction.