Molecular dynamics study of vibrational nonequilibrium and chemical reactions in shock waves

Abstract

Energy transfer mechanisms to internal molecular degrees of freedom in shock waves in polyatomic liquids are investigated. The proposed approach uses a new version of the method of nonequilibrium molecular dynamics based on the simplest model potential energy surfaces of reacting polyatomic molecules. The main feature is adaptation of some results and approaches of gas theory to liquids. It is shown that vibrational nonequilibrium is produced by shock compression and influences on chemical reactions. So, the structure of shock waves depends strongly on the peculiarities of vibrational spectra and the structure of normal modes of compounds. The results of numerical simulations demonstrate different shock wave chemistry for substances of almost identical behaviour at static conditions.