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Title: H 2 O time histories in the H 2 ‐NO 2 system for validation of NOx hydrocarbon kinetics mechanisms
Abstract The development and refinement of NOx chemical kinetic mechanisms have been instrumental in understanding and reducing NOx formation. However, relatively little work has been performed with NOx species as the oxidizer, and such experiments can provide unique insights into NOx kinetics. Furthermore, speciation data can often provide useful information that complements global measurements such as ignition delay times in facilitating mechanism refinement. To provide such speciation data in the H2‐NO2system, H2O measurements were performed using a fixed‐wavelength, direct absorption laser diagnostic near 1.39 µm behind reflected shock waves in fuel‐lean, near‐stoichiometric, and fuel‐rich mixtures of H2and NO2highly diluted in argon. Experiments were performed between 917 and 1782 K near atmospheric pressure. The H2O profiles obtained herein are markedly different from those using O2as the oxidizer obtained in a previous study. The GRI 3.0 mechanism was found to greatly underestimate the H2O formation, whereas two modern mechanisms were found to predict the H2O formation quite accurately except at colder temperatures for fuel‐rich conditions. Explanations for the differences between these mechanisms are given and discussed, with the conclusion that older mechanisms such as GRI 3.0 should not be used to model hydrocarbon/NOx combustion chemistry as they are lacking several key reactions and species, namely NO3and HONO. The discrepancy between models and data at lower temperatures could not be reconciled even when modifying two of the most‐sensitive reaction rates. To the best of the authors’ knowledge, this study presents the first shock‐tube speciation study in the H2‐NO2system.  more » « less
Award ID(s):
1706825
PAR ID:
10460033
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
International Journal of Chemical Kinetics
Volume:
51
Issue:
9
ISSN:
0538-8066
Page Range / eLocation ID:
p. 669-678
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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