Advanced

Formation of NO and NH in NH3-doped CH4 + N2 + O2 flame : Experiments and modelling

Brackmann, Christian LU ; Nilsson, Elna J.K. LU ; Nauclér, Jenny D. LU ; Aldén, Marcus LU and Konnov, Alexander A. LU (2018) In Combustion and Flame 194. p.278-284
Abstract

Co-combustion of 5200 ppm NH3 with a stoichiometric, atmospheric pressure, CH4 + N2 + O2 flame has been investigated with experiments and kinetic modelling. Profiles of the amidogen (NH) radical and nitric oxide (NO) have been measured using laser-induced fluorescence, the latter being quantitatively determined. Temperature profiles were measured using Rayleigh scattering and thermocouple, the nonintrusive measurements were considered more reliable and were used for evaluation of LIF data as well as input for flame modelling. Experimental results are compared with predictions of a chemical mechanism developed by Mendiara and Glarborg (2009), with simulations based on solution of energy... (More)

Co-combustion of 5200 ppm NH3 with a stoichiometric, atmospheric pressure, CH4 + N2 + O2 flame has been investigated with experiments and kinetic modelling. Profiles of the amidogen (NH) radical and nitric oxide (NO) have been measured using laser-induced fluorescence, the latter being quantitatively determined. Temperature profiles were measured using Rayleigh scattering and thermocouple, the nonintrusive measurements were considered more reliable and were used for evaluation of LIF data as well as input for flame modelling. Experimental results are compared with predictions of a chemical mechanism developed by Mendiara and Glarborg (2009), with simulations based on solution of energy equation as well as on experimental temperature profiles as input. Compared with a neat flame, the NH3-doped flame shows a shift in position ∼0.7 mm downstream, as established from the measurements of the NH profile. Modelling prediction of post-flame NO concentrations in the NH3-doped flame, around 1160 ppm, was within the evaluated uncertainty with experimental data (1460 ppm). Reaction path analysis indicated NH2 as a key species in the formation of NO and N2 from the nitrogen added to the flame by NH3. Altogether, the mechanism predicts concentration levels rather well but fails to predict the shift in flame position obtained with addition of NH3 to the rather slowly burning hydrocarbon flame.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Ammonia, Flame structure, Kinetic modelling, LIF
in
Combustion and Flame
volume
194
pages
7 pages
publisher
Elsevier
external identifiers
  • scopus:85047270115
ISSN
0010-2180
DOI
10.1016/j.combustflame.2018.05.008
language
English
LU publication?
yes
id
55cd88b8-8d84-4eb3-9136-aeab32941d5d
date added to LUP
2018-05-31 14:21:48
date last changed
2019-01-06 13:56:08
@article{55cd88b8-8d84-4eb3-9136-aeab32941d5d,
  abstract     = {<p>Co-combustion of 5200 ppm NH<sub>3</sub> with a stoichiometric, atmospheric pressure, CH<sub>4</sub> + N<sub>2</sub> + O<sub>2</sub> flame has been investigated with experiments and kinetic modelling. Profiles of the amidogen (NH) radical and nitric oxide (NO) have been measured using laser-induced fluorescence, the latter being quantitatively determined. Temperature profiles were measured using Rayleigh scattering and thermocouple, the nonintrusive measurements were considered more reliable and were used for evaluation of LIF data as well as input for flame modelling. Experimental results are compared with predictions of a chemical mechanism developed by Mendiara and Glarborg (2009), with simulations based on solution of energy equation as well as on experimental temperature profiles as input. Compared with a neat flame, the NH<sub>3</sub>-doped flame shows a shift in position ∼0.7 mm downstream, as established from the measurements of the NH profile. Modelling prediction of post-flame NO concentrations in the NH<sub>3</sub>-doped flame, around 1160 ppm, was within the evaluated uncertainty with experimental data (1460 ppm). Reaction path analysis indicated NH<sub>2</sub> as a key species in the formation of NO and N<sub>2</sub> from the nitrogen added to the flame by NH<sub>3</sub>. Altogether, the mechanism predicts concentration levels rather well but fails to predict the shift in flame position obtained with addition of NH<sub>3</sub> to the rather slowly burning hydrocarbon flame.</p>},
  author       = {Brackmann, Christian and Nilsson, Elna J.K. and Nauclér, Jenny D. and Aldén, Marcus and Konnov, Alexander A.},
  issn         = {0010-2180},
  keyword      = {Ammonia,Flame structure,Kinetic modelling,LIF},
  language     = {eng},
  month        = {08},
  pages        = {278--284},
  publisher    = {Elsevier},
  series       = {Combustion and Flame},
  title        = {Formation of NO and NH in NH<sub>3</sub>-doped CH<sub>4</sub> + N<sub>2</sub> + O<sub>2</sub> flame : Experiments and modelling},
  url          = {http://dx.doi.org/10.1016/j.combustflame.2018.05.008},
  volume       = {194},
  year         = {2018},
}