A fully integrated kinetic monte carlo/molecular dynamics approach for the simulation of soot precursor growth

• Published in: Proceedings of the Combustion Institute Vol. 29; no. 2; pp. 2343 - 2349
• Main Authors: Violi, A., Kubota, A., Truong, T.N., Pitz, W.J., Westbrook, C.K., Sarofim, A.F.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 2002
• ISSN: 1540-7489; 1873-2704
• DOI: 10.1016/S1540-7489(02)80285-1

The emphasis in this paper is on presenting a new methodology, together with some illustrative applications, for the study of polycyclic aromatic hydrocarbon polymerization leading to soot, widely recognized as a very important and challenging combustion problem. The new code, named fully integrated Kinetic Monte Carlo/Molecular Dynamics (KMC/MD), places the two simulation procedures on an equal footing and involves alternating between KMC and MD steps during the simulation. The KMC/MD simulations are used in conjunction with high-level quantum chemical calculations. With traditional kinetic rates and dealing with the growth of particles, it is often necessary to perform a lurnping procedure in which much atomic-scale information is lost. Our KMC/MD approach is designed to preserve atomic-scale structure: a single particle evolves in time with real three-dimensional structure (bonds, bond angles, dihedralangles). In this paper, the methodology is illustrated by a sample simulation of high molecular mass compound growth in an environment (T, H, H
2, naphthalene, and acenaphthylene concentrations) of a low-pressure laminar premixed benzene/oxygen/argon flame with an equivalence ratio of 1.8. The use of this approach enables the investigation of the physical (e.g., porosity, density, sphericity) as well as chemical (e.g. H/C, aromatic moieties, number of cross-links) properties.