Vibrational State-to-State and Shock-tube Thermochemical Modeling of Hypersonic Flows

Hypersonic flows give rise to nonequilibrium conditions that require increased precision and more specialized simulations to model the collisions between excited gas molecules. While the rotational energy mode is often in equilibrium with the translation mode, the vibrational mode requires more collisions, and thus more time, to reach equilibrium. In this paper, we investigate four main areas of interest. First, state-resolved rates are often generated on different potential energy surface so we investigate ways to do a consistent mapping from one energy surface to another. Next, vibrational state-to-state modeling is investigated, through analysis of existing data and the implementation into existing hypersonic code. Due to differences in energy levels between existing data, data mapping methods are investigated to ensure uniformity in simulations. Further, nonequilibrium effects for canonical flows are modeled using both one-temperature and two-temperature models. Finally, the modeling of one-dimensional shock f lows is investigated to prepare for the introduction of state-to-state models within these shock f lows.