Modeling of Chemical Reactions in Rarefied Gas Flows by the Kinetic Fokker-Planck Method

Abstract: We propose a novel approach for modeling chemical reactions within the particle-based Fokker-Planck framework for gas flow simulations which conserves mass, momentum, and energy while retaining the performance advantages of the Fokker-Planck approach over the Direct Simulation Monte Carlo (DSMC) method in areas of high density. We show an application of the approach to recombination and exchange reactions, discuss verification results, and demonstrate performance advantages when compared to DSMC for applications in low Knudsen number regimes. The developed method can be applied to simulation of flows in the continuum and transitional regimes, as well as to multi-scale coupled Fokker-Planck-DSMC simulations.