@article{af6ae40efe804c2ea4e64401471909e3,
title = "Effect of Oxygen Dissociation on Nitric Oxide Ultraviolet Emissions",
abstract = "Hypersonic flow over a cylinder was modeled using the direct simulation Monte Carlo method to study how nitric oxide (NO) Ultraviolet emission profiles are a test of high-fidelity thermochemical, nonequilibrium models. For pressures found in typical hypersonic ground facilities, it was shown that the ultraviolet radiation emission profiles are very close to those calculated by assuming Boltzmann equilibrium conditions. Therefore, the NO emission profiles can be tied directly to the ground state NO concentration and flow bulk temperature. Two chemical models differing in the manner in which molecular oxygen is dissociated were considered in this classic canonical-type flow. A comparison of the predicted flowfields with schlieren imagery and surface pressure measurements from previous experiments showed good agreement; however, the sensitivity of these measurements to change in different freestream species concentrations was not found to be strong. Instead, the shapes of the predicted NO integrated emission spatial profiles were observed to be highly sensitive to whether vibrational favoring was considered in the oxygen dissociation model for the same freestream conditions.",
author = "Karpuzcu, \{Irmak T.\} and Jouffray, \{Matthew P.\} and Levin, \{Deborah A.\}",
note = "The research being performed at the University of Illinois at Urbana–Champaign is supported by the United States Air Force Office of Scientific Research through grant no. FA9550-19-1-0342. Matthew P. Jouffray received a Graduate Assistance in Areas of National Need Fellowship from the United States Department of Education. Computational resources for this research are provided by the National Science Foundation Texas Advanced Computing Center Stampede2 supercomputer, which is a part of The Extreme Science and Engineering Discovery Environment, with project number TG-ATM200010. The authors would like to thank Sergey F. Gimelshein and Ingrid Wysong for providing the bias Larsen–Borg-nakke model setup and useful discussions, as well as Nelson J. Yanes and Joanna Austin for discussions about ground-based facility emission measurements in the California Institute of Technology{\textquoteright}s hypervelocity expansion tube facility. The research being performed at the University of Illinois at Urbana–Champaign is supported by the United States Air Force Office of Scientific Research through grant no. FA9550-19-1-0342. Matthew P. Jouffray received a Graduate Assistance in Areas of National Need Fellowship from the United States Department of Education. Computational resources for this research are provided by the National Science Foundation Texas Advanced Computing Center Stampede2 supercomputer, which is a part of The Extreme Science and Engineering Discovery Environment, with project number TG-ATM200010. The authors would like to thank Sergey F. Gimelshein and Ingrid Wysong for providing the bias Larsen–Borgnakke model setup and useful discussions, as well as Nelson J. Yanes and Joanna Austin for discussions about ground-based facility emission measurements in the California Institute of Technology{\textquoteright}s hypervelocity expansion tube facility.",
year = "2023",
month = jan,
doi = "10.2514/1.T6609",
language = "English (US)",
volume = "37",
pages = "147--160",
journal = "Journal of thermophysics and heat transfer",
issn = "0887-8722",
publisher = "AIAA International",
number = "1",
}