Abstract
We report a numerical study of vibration-dissociation coupling which is one of the most important thermochemical relaxation phenomena in hypersonic flows around a reentry capsule. A full set of vibrational master equations was numerically solved to obtain time-resolved population distribution of the vibrational states as well as bulk properties during the relaxation process. State-resolved rate coefficients were determined using the information theoretical approach. Our results show that a quasi-steady state (QSS) exists during the relaxation process, and that the bulk dissociation mostly proceeds during the QSS. It is also shown that the high-lying vibrational energy levels are depleted during the QSS and that the severe depletion of high-lying levels strongly affects the average dissociation rate coefficient and the average vibrational energy loss due to dissociation.
