TY - JOUR

T1 - Kinetic and Continuum Modeling of High Temperature Air Relaxation

AU - Gimelshein, Sergey F.

AU - Wysong, Ingrid J.

AU - Fangman, Alexander J.

AU - Andrienko, Daniil A.

AU - Kunova, Olga

AU - Kustova, Elena

AU - Morgado, Fabio

AU - Garbacz, Catarina

AU - Fossati, Marco

AU - Hanquist, Kyle M.

N1 - Publisher Copyright: © 2022 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.

PY - 2022/10

Y1 - 2022/10

N2 - Fully kinetic, vibrationally kinetic, and continuum solvers with varying model fidelity are used in this work to model the high-temperature relaxation of air in 7230 and 15,000 K adiabatic heat baths and a 6 km/s hypersonic flow over a cylinder. The results show significant impact of uncertainties in vibrational relaxation times and reaction rate constants on thermal and chemical relaxation, in particular, on gas temperature and species mole fractions. Most notably, these uncertainties need to be reduced for collisions that include nitric oxide. Order-of-magnitude differences in the nitric oxide dissociation and recombination rates have a large impact on the peak NO mole fraction immediately behind the shock and surface-distributed heat flux, respectively. High-fidelity kinetic and continuum approaches are found to have different reaction channels having the largest effect on species mole fractions and gas temperature: N-2+O exchange and O-2+O dissociation in the former, and NO+O and O-2+N-2 dissociation in the latter.

AB - Fully kinetic, vibrationally kinetic, and continuum solvers with varying model fidelity are used in this work to model the high-temperature relaxation of air in 7230 and 15,000 K adiabatic heat baths and a 6 km/s hypersonic flow over a cylinder. The results show significant impact of uncertainties in vibrational relaxation times and reaction rate constants on thermal and chemical relaxation, in particular, on gas temperature and species mole fractions. Most notably, these uncertainties need to be reduced for collisions that include nitric oxide. Order-of-magnitude differences in the nitric oxide dissociation and recombination rates have a large impact on the peak NO mole fraction immediately behind the shock and surface-distributed heat flux, respectively. High-fidelity kinetic and continuum approaches are found to have different reaction channels having the largest effect on species mole fractions and gas temperature: N-2+O exchange and O-2+O dissociation in the former, and NO+O and O-2+N-2 dissociation in the latter.

KW - DISSOCIATION

KW - MONTE-CARLO-SIMULATION

KW - RATES

KW - VIBRATIONAL-ENERGY TRANSFER

UR - https://www.mendeley.com/catalogue/9fab000e-eeae-3540-805a-04ce76325ca9/

UR - http://www.scopus.com/inward/record.url?scp=85133744914&partnerID=8YFLogxK

U2 - 10.2514/1.T6462

DO - 10.2514/1.T6462

M3 - Article

VL - 36

SP - 870

EP - 893

JO - Journal of Thermophysics and Heat Transfer

JF - Journal of Thermophysics and Heat Transfer

SN - 0887-8722

IS - 4

ER -