Humidified combustion of hydrocarbon fuel can cause changes in combustion temperature and intermediate products

and then affect the generation of soot. Based on the finite rate chemical reaction model

the effect of water vapor addition on flame and soot volume fraction of ethylene laminar diffusion flame at atmospheric pressure was numerically studied by using simplified 23-step ethylene gas phase reaction mechanism

thermodynamics and transport data. Through the design of various working conditions and the construction of nonreactive material FH_2 O

the effects of water vapor on soot were studied. The results show that

humidified combustion can reduce the flame temperature and soot volume fraction. The added water vapor not only affects the soot formation and flame shape through dilution and thermal effects

but also affects the mole fraction of key species H and OH through chemical effects

and then affects the soot formation process. The important degrees of multiple effects caused by the addition of water vapor are dilution effect

thermal effect and chemical effect in turn.