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Simultaneous one-dimensional fluorescence lifetime measurements of OH and CO in premixed flames

Jonsson, Malin LU ; Ehn, Andreas LU ; Christensen, Moah LU ; Aldén, Marcus LU and Bood, Joakim LU (2014) In Applied Physics B 115(1). p.35-43
Abstract
A method for simultaneous measurements of fluorescence lifetimes of two species along a line is described. The experimental setup is based on picosecond laser pulses from two tunable optical parametric generator/optical parametric amplifier systems together with a streak camera. With an appropriate optical time delay between the two laser pulses, whose wavelengths are tuned to excite two different species, laser-induced fluorescence can be both detected temporally and spatially resolved by the streak camera. Hence, our method enables one-dimensional imaging of fluorescence lifetimes of two species in the same streak camera recording. The concept is demonstrated for fluorescence lifetime measurements of CO and OH in a laminar methane/air... (More)
A method for simultaneous measurements of fluorescence lifetimes of two species along a line is described. The experimental setup is based on picosecond laser pulses from two tunable optical parametric generator/optical parametric amplifier systems together with a streak camera. With an appropriate optical time delay between the two laser pulses, whose wavelengths are tuned to excite two different species, laser-induced fluorescence can be both detected temporally and spatially resolved by the streak camera. Hence, our method enables one-dimensional imaging of fluorescence lifetimes of two species in the same streak camera recording. The concept is demonstrated for fluorescence lifetime measurements of CO and OH in a laminar methane/air flame on a Bunsen-type burner. Measurements were taken in flames with four different equivalence ratios, namely I center dot = 0.9, 1.0, 1.15, and 1.25. The measured one-dimensional lifetime profiles generally agree well with lifetimes calculated from quenching cross sections found in the literature and quencher concentrations predicted by the GRI 3.0 mechanism. For OH, there is a systematic deviation of approximately 30 % between calculated and measured lifetimes. It is found that this is mainly due to the adiabatic assumption regarding the flame and uncertainty in H2O quenching cross section. This emphasizes the strength of measuring the quenching rates rather than relying on models. The measurement concept might be useful for single-shot measurements of fluorescence lifetimes of several species pairs of vital importance in combustion processes, hence allowing fluorescence signals to be corrected for quenching and ultimately yield quantitative concentration profiles. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Applied Physics B
volume
115
issue
1
pages
35 - 43
publisher
Springer
external identifiers
  • wos:000332853000004
  • scopus:84899408215
ISSN
0946-2171
DOI
10.1007/s00340-013-5570-7
language
English
LU publication?
yes
id
229bb4ba-25ab-4522-aa34-449c182e2f9a (old id 4410898)
date added to LUP
2014-04-29 10:54:58
date last changed
2017-06-25 03:11:06
@article{229bb4ba-25ab-4522-aa34-449c182e2f9a,
  abstract     = {A method for simultaneous measurements of fluorescence lifetimes of two species along a line is described. The experimental setup is based on picosecond laser pulses from two tunable optical parametric generator/optical parametric amplifier systems together with a streak camera. With an appropriate optical time delay between the two laser pulses, whose wavelengths are tuned to excite two different species, laser-induced fluorescence can be both detected temporally and spatially resolved by the streak camera. Hence, our method enables one-dimensional imaging of fluorescence lifetimes of two species in the same streak camera recording. The concept is demonstrated for fluorescence lifetime measurements of CO and OH in a laminar methane/air flame on a Bunsen-type burner. Measurements were taken in flames with four different equivalence ratios, namely I center dot = 0.9, 1.0, 1.15, and 1.25. The measured one-dimensional lifetime profiles generally agree well with lifetimes calculated from quenching cross sections found in the literature and quencher concentrations predicted by the GRI 3.0 mechanism. For OH, there is a systematic deviation of approximately 30 % between calculated and measured lifetimes. It is found that this is mainly due to the adiabatic assumption regarding the flame and uncertainty in H2O quenching cross section. This emphasizes the strength of measuring the quenching rates rather than relying on models. The measurement concept might be useful for single-shot measurements of fluorescence lifetimes of several species pairs of vital importance in combustion processes, hence allowing fluorescence signals to be corrected for quenching and ultimately yield quantitative concentration profiles.},
  author       = {Jonsson, Malin and Ehn, Andreas and Christensen, Moah and Aldén, Marcus and Bood, Joakim},
  issn         = {0946-2171},
  language     = {eng},
  number       = {1},
  pages        = {35--43},
  publisher    = {Springer},
  series       = {Applied Physics B},
  title        = {Simultaneous one-dimensional fluorescence lifetime measurements of OH and CO in premixed flames},
  url          = {http://dx.doi.org/10.1007/s00340-013-5570-7},
  volume       = {115},
  year         = {2014},
}