Acetylene(C2H2)is one of the significant intermediates or products during the combustion of many hydrocarbon fuels,particularly under fuel-rich conditions.It plays an important role in soot formation and soot-particle growth,which is a key combustion-derived air pollutant known to be harmful to both the human health and environment.Although there are a variety of studies on the flame,pyrolysis and oxidation of C2H2 available in the literature,aromatic species were rarely observed in the low-temperatue experiments and the predictions for the formation of benzene by the proposed mechanism were even scarce.Specifically,experimental and kinetic modeling study on the low-temperature oxidation of C2H2 is of great importance in understanding the soot formation mechanism.However,the low-temperature oxidation data of C2H2 in a full range of equivalence rations,especially under fuel-rich conditions,were scarcely reported in the literature.