Study On The Reaction Process Of Intermediate Product Of Soot Formation Of N-heptane Laminar Flame

Combustion equipment contains a variety of combustion methods in fact,the most important of which is the diffusion of flame.The former is more prone to contaminants,including polycyclic aromatic hydrocarbons and soot.The main source of soot emissions is the combustion equipment based on the form of diffusion flame combustion.Diffusion flame structures have axisymmetric properties,so it is easy to study in fluid simulation studies.In this paper,numerical simulations of n-heptane/oxygen co-flow diffusion flame under high pressure were studied with selected chemical reaction kinetic mechanism model on LaminarSMOKE program.At present,there are few reports on the experimental and simulation of the laminar flame of n-heptane.In this study,the intermediate products of the laminar flame of n-heptane under high pressure were studied.N-Heptane is a good alternative fuel for liquid transportation fuels owing to simple molecular structure and unsaturated double bond structure,n-heptane is a typical alternative to study the mechanism of PAH and soot formation during combustion of liquid fuels.This paper first selects several mechanisms such as POLIMI,Li,UCRL,USC and GRI,and uses laminarSMOKE to simulate the laminar diffusion flame experiment of n-heptane/air under high pressure to select good mechanisms.Through the simulation results,result shows the GRI mechanism has best performance.Finally,using the mechanism to simulate the experiment and compared with experiment had been successfully simulated.In order to predict the decomposition of fuel and the formation of aromatics,the paper uses the LaminarSMOKE program to simulate the n-heptane with GRI and Li mechanism.The generation rate analysis(ROP)based on the simulation results shows the main consumption of fuel is oxidized by the oxidant.The intermediate soot of soot with important small molecules such as CH2,CH4,C2H4,C2H2 and C3H6,and analysis the important formation of macromolecular species benzene,phenylacetylene(A1C2H),ethylene(A1C2H3)and naphthalene(A2)in the simulation,the important reactions affecting them and the small molecules involved in the reaction were obtained by ROP analysis.The important path of A2 was C3H3=>benzene=>Phenyl =>A2 through the analysis of the reaction pathway.