We carried out numerical studies on methane/oxygen diffusion flames of counter-flow configuration to elucidate the influence of pressure on flame structure, heat release rate and reaction mechanisms. The chemistry in gas-phase was based on GRI-Mech 3.0 database. The thickness of diffusion flame became thinner with increasing strain rate
a , with its characteristic flame thickness varying inversely with √
a, especially its relation became significant with increasing pressure. Flame temperature increased with increasing pressure. Enhanced H
2O production reactions, especially chain terminal reactions for H
2O production, were found to be important in determining the flame temperature at high pressures. The small reduction in the flame temperature with increasing strain rate at high pressures, compared to the atmospheric pressure, is caused by the capacitor effect of product dissociation. From QRPDs, the third body dependent reactions were enhanced in high pressure conditions, hence C
2 pathway was enhanced.
抄録全体を表示