We present a molecular level study of vibrational excitation and non-equilibrium dissociation of diatomic oxygen due to O2 + O interactions. O2 + O interactions are modeled using nine potential energy surfaces corresponding to 11A′, 21A′, 11A′′, 13A′, 23A′, 13A′′ 15A′, 25A′ and 15A′′ states, which govern electronically adiabatic collisions of ground-electronic-state collisions of diatomic oxygen with atomic oxygen. Characteristic vibrational excitation times are calculated over a temperature range of T = 3000 K to T = 15000 K. We observe that the characteristic vibrational excitation time for O2 + O interactions is weakly dependent on temperature and increases slightly with increasing temperature. Vibrational excitation is slowest for interactions in the quintet spin state, with the 15A′′ state having the slowest excitation rate, and vibrational excitation is fastest on the 11A′ potential energy surface. Dissociation rate coefficients in the quasi-steady state agree well with experimental data. Furthermore, dissociation during the quasi-steady state is found to be three times faster when O2 + O interactions are included, compared to simulations including only O2 + O2 interactions.
|Original language||English (US)|
|Title of host publication||AIAA Aerospace Sciences Meeting|
|Publisher||American Institute of Aeronautics and Astronautics Inc, AIAA|
|State||Published - 2018|
|Event||AIAA Aerospace Sciences Meeting, 2018 - Kissimmee, United States|
Duration: Jan 8 2018 → Jan 12 2018
|Name||AIAA Aerospace Sciences Meeting, 2018|
|Other||AIAA Aerospace Sciences Meeting, 2018|
|Period||1/8/18 → 1/12/18|
Bibliographical noteFunding Information:
The authors are grateful to Antonio Varandas and Yuliya Paukku for many discussions of the O3 problem over the years. The research presented here is supported by the Air Force Office of Scientific Research (AFOSR) under grant no. FA9550-16-1-0161. The views and conclusions contained herein are those of the authors and should not be interpreted as representing the official policies or endorsements, either expressed or implied, of the AFOSR or the US government.
© 2018, American Institute of Aeronautics and Astronautics Inc, AIAA. All rights reserved.