2019 AIChE Annual Meeting
(376ay) Elucidating Biofuel Sooting Mechanisms: A Combined Reaxff and DFT Study
Authors
Messerly, R. A. - Presenter, National Renewable Energy Laboratory
Etz, B., National Renewable Energy Laboratory
Kwon, H., Penn State University
In this study, reactive molecular dynamics (RMD) is employed as an automated approach for proposing reaction
networks. Although the atomic forces for RMD would ideally be computed with high level
ab initio methods or even density functional theory (DFT), the nano- to millisecond time scales
that are required to observe combustion chemistry at moderate temperatures and pressures are
much too long for DFT-RMD to be feasible. By contrast, the reactive force field (ReaxFF)
renders classical RMD computationally tractable. ReaxFF simulations are performed for various biofuels to investigate
networks. Although the atomic forces for RMD would ideally be computed with high level
ab initio methods or even density functional theory (DFT), the nano- to millisecond time scales
that are required to observe combustion chemistry at moderate temperatures and pressures are
much too long for DFT-RMD to be feasible. By contrast, the reactive force field (ReaxFF)
renders classical RMD computationally tractable. ReaxFF simulations are performed for various biofuels to investigate
the soot formation mechanism. Subsequent to the RMD simulations, traditional DFT transition state calculations are used to validate the ReaxFF-predicted reaction pathways.