TY - GEN
T1 - A multi-group maximum entropy model for thermo-chemical nonequilibrium
AU - Liu, Yen
AU - Vinokur, Marcel
AU - Panesi, Marco
AU - Magin, Thierry
PY - 2010
Y1 - 2010
N2 - This paper deals with the proper formulation of the macroscopic equations of high temperature hypersonic flow in the presence of nonequilibrium phenomena such as vibrational, rotational and electronic excitation, dissociation, ionization, and thermal radiation. A multi-group model based on the maximum entropy principle is presented. Quantum states of each species are divided into groups. Translational equilibrium but thermo-chemical nonequilibrium among groups is assumed. The internal temperature of each group is proportional to the inverse of the Lagrange multiplier for the total internal energy constraint for that group to reach maximum entropy. Macroscopic equations for group population and internal energy are derived from moments of the master equations. Microscopic rate coefficients are obtained from a quasi-classical trajectory method or a quantum dynamics method. Macroscopic group rate coefficients for internal excitation, dissociation, ionization, internal energy - translational and radiative energy exchange, and internal - chemical reaction coupling are then determined. The proposed model allows all possible collisional and radiative transitions. Current vibrational nonequilibrium models and collisional-radiative models are special cases of the proposed model.
AB - This paper deals with the proper formulation of the macroscopic equations of high temperature hypersonic flow in the presence of nonequilibrium phenomena such as vibrational, rotational and electronic excitation, dissociation, ionization, and thermal radiation. A multi-group model based on the maximum entropy principle is presented. Quantum states of each species are divided into groups. Translational equilibrium but thermo-chemical nonequilibrium among groups is assumed. The internal temperature of each group is proportional to the inverse of the Lagrange multiplier for the total internal energy constraint for that group to reach maximum entropy. Macroscopic equations for group population and internal energy are derived from moments of the master equations. Microscopic rate coefficients are obtained from a quasi-classical trajectory method or a quantum dynamics method. Macroscopic group rate coefficients for internal excitation, dissociation, ionization, internal energy - translational and radiative energy exchange, and internal - chemical reaction coupling are then determined. The proposed model allows all possible collisional and radiative transitions. Current vibrational nonequilibrium models and collisional-radiative models are special cases of the proposed model.
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M3 - Conference contribution
AN - SCOPUS:78649621897
SN - 9781600867453
T3 - 10th AIAA/ASME Joint Thermophysics and Heat Transfer Conference
BT - 10th AIAA/ASME Joint Thermophysics and Heat Transfer Conference
T2 - 10th AIAA/ASME Joint Thermophysics and Heat Transfer Conference
Y2 - 28 June 2010 through 1 July 2010
ER -