The combustion mechanism of leaking propane (R290) in O2 and O2/H2O environments: ReaxFF molecular dynamics and density functional theory study

Abstract

Propane (R290) is a widely used environmentally friendly refrigerant with excellent thermodynamic properties, but it may burn once it leaks. Therefore, it is imperative to investigate the combustion mechanism of leaking propane. A series of ReaxFF molecular dynamic simulations were employed, and the reactions involving the decomposition of propane were investigated by density functional theory (DFT), and the results of the ReaxFF molecular dynamic simulations were clarified by comparing the energy barriers, bond dissociation energies and reaction energies required for the reactions. The results indicated that the chemical role of H2O was mainly reflected by the reactions of H2O molecules with H and O radicals to form OH radicals and H2 molecules. The combustion of propane was promoted by the presence of a low concentration of H2O molecules.