Measurement of Flame Front Structure and Burning Velocity of Premixed Turbulent Flames ofCH4/Air and C3H8/Air
Measurement of the instantaneous flame front structure of premixed turbulent flames of CH4/air and C3H8/air mixtures was conducted using OH-PLIF technique.A variety of stable turbulenceintensity was generated by perforated plates and laminar flame parameters were calculated.The effects of turbulence intensity and flame charac-teristics on turbulent flame structure and turbulent burning velocity were analyzed.Results showed that with the in-crease of turbulence intensity,the wrinkled intensity of flame front structure increased.For the same turbulence in-tensity,CH4/air mixtures have more wrinkled flame front than C3H8/air mixtures.The flame front structure was ob-tained from the OH-PLIF images and the turbulent burning velocity was calculated by angle method and area method.The correlation was proposed to fit the turbulent burning velocity and turbulence intensity under weak turbu-lence.Meanwhile,at the same density ratio,i.e., with the same hydrodynamic instability,CH4/air with greater thermo-diffusive instability shows higher turbulent burning velocity than C3H8/air.Moreover,with similarLewis number and less significant role of thermo-diffusive instability,CH4/air with larger density ratio has greater hydrody-namic instability,which has a significant influence on turbulent burning velocity.
planar laser induced fluorescence(PLIF)premixed turbulent flameflame front structureturbulent burning velocityinstability
NETL
NSTL
万方数据
维普
