KINETIC MONTE CARLO–MOLECULAR DYNAMICS APPROACH TO MODEL SOOT INCEPTION

Abstract

The processes involved in soot precursor formation exhibit a wide range of timescales, spanning pico- or nanoseconds for intramolecular processes that can occur on a particle surface to milliseconds for the formation of the first soot precursors. To accurately describe the soot formation process, it is important to model the reactions happening at different timescales. The use of atomistic models allows this. The code, named KMC/MD, combines the strengths of Kinetic Monte Carlo for long-time sampling, and Molecular Dynamics for relaxation processes. It enables the investigation of physical as well as chemical properties of the carbonaceous nanoparticles formed, such as particle morphology and concentration of free radicals.

Keywords:

• Molecular Dynamics
• Kinetic Monte Carlo
• soot inception

This research is funded by the University of Utah Center for the Simulation of Accidental Fires and Explosions and funded by the Department of Energy, Lawrence Livermore National Laboratory (LLNL), under subcontract B341493. The calculations presented in this paper were carried out at the Utah Center for High Performance Computing, University of Utah, which is acknowledged for computer time support. The authors are grateful to A. Kubota of LLNL for making available the KMC/MD code that formed the original building block for the model used here.