Effects of Diluents Addition on Laminar Burning Velocity of Premixed Methane Flames

Abstract:

Based on the GRIMech 3.0 mechanism,the premixed laminar combustion characteristics of methaneairdiluent mixtures were investigated by using PREMIXED Code.Several fundamental parameters,such as flame structure,laminar burning velocity,and flame thickness,were calculated at different equivalence ratios,initial pressures,and dilution ratios.It was found that increasing the dilution ratio in the mixture would lead to a decrease in laminar burning velocity and an increase of flame thickness.As a result,the hydrodynamic instability of methaneair laminar flame was suppressed with the addition of diluents,especially in the condition of CO2 dilution.When the initial pressure increased,the laminar burning velocity and flame thickness decreased accordingly.However,a further increase of the initial pressure did not have much effect on the flame thickness.