Diffusion filtration combustion is a new combustion technology

which combines some characteristics of diffusion combustion and premixed filtration combustion.A numerical study of diffusion filtration flame characteristics in a nitrogen diluted CH4+N2/O2 co-flow plane-parallel is conducted using a two-dimensional two-temperature model with a simple reaction rate mechanism.Both thermal and species dispersion effects are taken into account.The effects of pellet diameter(d)

gas mixture velocity(ug)and mass fraction of CH4(YCH4)

etc.on the flame shape and flame height are investigated.Results show that high gas and solid temperature zones exist at different locations compared to the premixed filtration combustion

and that in the area aside of the high temperature zone the differences between the gas and porous solid temperatures are very small.Flame height increases from 0.048 m to 0.12 m as d decreases from 6.66 mm to 2.02 mm.Increases in ug and YCH4 reduce the flame width and flame height.The calculated result is verified by experimental data.