Thermochemical Nonequilibrium Modeling of Electronic Energy in Hypersonic Flows

In this work, we propose the thermochemical nonequilibrium model for electronic energy for hypersonic air flows. To decompose high-fidelity physical data into macroscopic quantities, electronic state-to-state analyses were conducted using isolated chemical reactor calculations. The excitation of electronic energy induced by heavy particle and electron impacts was analyzed, and the preferential behavior of electronic states in chemical reactions were investigated. Based on these findings, the electronic relaxation time, electron-electronic coupled ionization reaction rates, and the electronic energy loss ratio due to chemical reactions are proposed as parameters for modeling the thermochemical nonequilibrium of electronic energy. The proposed set of parameters was implemented in the formulation that separates the electronic energy pools from the free-electron. To investigate the validity of the proposed model, a calculation of nonequilibrium air behind a strong shock wave are simulated. The results show improved accuracy in representing the nonequilibrium behavior of electronic energy