Sooting Characteristics of C10 Hydrocarbons from Reactive Molecular Dynamics Simulations

FRANCISCO GUZMAN, Deniz Kaya Eyice, Julien Manin, NASA Glenn Research Center

     Abstract Number: 172
     Working Group: Combustion

Abstract
We present the results of ReaxFF reactive molecular dynamic simulations of C10 hydrocarbon species under pyrolysis conditions between 2000 and 3500 K. We studied decane, butylcyclohexane, decalin, tetralin, and naphthalene, which differ in their molecular structure, aromaticity and sooting propensity as quantified by their yield sooting index (YSI). Simulations are carried out up to 3 nanoseconds where incipient particle formation is visible. Results show that for C10 species with low sooting propensity (YSI up to 110) the structure of the particle is amorphous and the surface highly branched. For high sooting species (300 < YSI < 470) the simulations are showing a core-shell like structure. Analysis of the initial parent fuel decomposition steps show increasing complexity with aromaticity highlighting chemical pathways and species that are not necessarily considered in chemical mechanisms. The results show that reactive molecular dynamics simulations with ReaxFF can be a powerful tool fuel sensitive tool for understanding the chemical pathways of soot formation.