Application of Parallel Replica Dynamics to Pyrolysis of n-Hexadecane

O. Kum, B.M. Dickson, S.J. Stuart, B.P. Uberuaga, and A.F. Voter (USA)

Keywords

Parallel replica dynamics, AIREBO, pyrolysis, linearalkane, hexadecane, Beowulf cluster

Abstract

Parallel replica dynamics has been applied to high temperature chemical reactions of n-hexadecane. To de couple the frequent conformational transitions from the much less frequent covalent bond dissociation and isomer ization reactions, a novel transition detection algorithm was used. This algorithm uses changes in bond network topol ogy, rather than atomic coordinates, to distinguish between molecular states. Simulations were performed at tempera tures ranging from 2300 K to 2800 K, closer to experimen tal conditions than previous simulations by several hun dred degrees. In a total of over 4.5 µs of dynamics, five different types of chemical reactions were observed that are relevant for parameterizing kinetic models of pyroly sis: (1) carbon-carbon dissociation, (2) carbon-hydrogen dissociation, (3) intramolecular hydrogen transfer, (4) in tramolecular cyclization, and (5) ring breaking. Among the five primary reactions, carbon-hydrogen dissociation and hydrogen transfer reactions were dominant. The cal culations were performed using 61 processors of Clemson University’s 512-processor Computational Minigrid Super computing Facility.

Important Links:



Go Back