Open-source direct simulation Monte Carlo chemistry modeling for hypersonic flows

An open-source implementation of chemistry modeling for the direct simulation Monte Carlo method is presented. Following the recent work of Bird (Bird, G. A., "The Q-K Model for Gas Phase Chemical Reaction Rates," Physics of Fluids, Vol. 23, No. 10, 2011, Paper 106101), an approach known as the quantum-kinetic method has been adopted to describe chemical reactions in a five-species air model using direct simulation Monte Carlo procedures based on microscopic gas information. The quantum-kinetic technique has been implemented within the framework of the dsmcFoam code, a derivative of the open-source computational-fluid-dynamics code OpenFOAM. Results for vibrational relaxation, dissociation, and exchange reaction rates for an adiabatic bath demonstrate the success of the quantum-kinetic model implementation in dsmcFoam when compared with analytical solutions for both inert and reacting conditions. A comparison is also made between the quantum-kinetic and total collision energy chemistry approaches for a hypersonic flow benchmark case.