Reactive Collisions and Final State Analysis of C- and O-Involving Reactions Relevant to the Hypersonic Flight Regime
Abstract
Airflow and matter during hypersonic flight is in thermal non-equilibrium. This is particularly relevant for re-entry of vehicles into the atmosphere because the high velocities lead to complex chemistry. The ablated material in the flow around and at the solid(vehicle)/gas(vehicle surface and atmospheric environment) interface is in thermal non-equilibrium because the timescales and velocities of the flow do not allow the material to come to chemical and thermal equilibrium. Hence, the temperature of the medium around such a vehicle can easily reach several thousand Kelvin. Interactions between gases, in equilibrium or not, at these temperatures are essentially uncharacterized and the experimental methodologies capable of probing them at a molecular and state-resolved level are extremely limited. Given the experimental difficulties in measuring the relevant quantities, an alternative source for non-equilibrium rates for gas-gas chemistry is to use accurate and validated molecular dynamics (MD) and quantum mechanical (QM) simulations based on high-accuracy intermolecular interaction potentials. The present proposal employs state-of-the-art quantum chemistry and classical/quantum dynamics simulations to calculate the cross sections and reaction rate coefficients for gas phase reactions involving C- and O-containing species important to atmospheric re-entry. This information is subsequently used in chemical reaction network simulations. The proposal also introduces a novel approach to determine state-to-state cross sections based on quasiclassical simulations and neural networks.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 24, 2019
- Source ID
- FA95501817013
Entities
People
- Markus Meuwly
Organizations
- Air Force Office of Scientific Research
- United States Air Force
- University of Basel