Strategy for single-shot CH3 imaging in premixed methane/air flames using photofragmentation laser-induced fluorescence
(2017) In Proceedings of the Combustion Institute p.4487-4495- Abstract
Single-shot imaging of methyl radical (CH3) in premixed methane/air flames is demonstrated using photofragmentation laser-induced fluorescence (PF-LIF) technique. A pump-probe strategy was adopted with the pump laser at 212.8 nm photolyzing CH3, and with the probe laser at 426.8 nm detecting the photolyzed CH (X 2Π) fragments. Spatially resolved spectrograph of the PF-LIF signal from a stable laminar flame was recorded across the reaction zone to investigate potential interferences. The results indicate that the single-photon channel, CH3 + 212.8 nm → CH (X 2Π) + H2, dominates the photofragmentation process. The CH2 radical was excluded from being an... (More)
Single-shot imaging of methyl radical (CH3) in premixed methane/air flames is demonstrated using photofragmentation laser-induced fluorescence (PF-LIF) technique. A pump-probe strategy was adopted with the pump laser at 212.8 nm photolyzing CH3, and with the probe laser at 426.8 nm detecting the photolyzed CH (X 2Π) fragments. Spatially resolved spectrograph of the PF-LIF signal from a stable laminar flame was recorded across the reaction zone to investigate potential interferences. The results indicate that the single-photon channel, CH3 + 212.8 nm → CH (X 2Π) + H2, dominates the photofragmentation process. The CH2 radical was excluded from being an interfering precursor of the CH (X 2Π) fragments owing to its relatively low concentration and small absorption cross section. Naturally present CH in the flame was identified as the main interference, but was conservatively estimated to account for only less than 4% of the total PF-LIF signal. Signal-to-noise ratio of around 10 was realized for single-shot imaging of natural CH3 in turbulent jet flames.
(Less)
- author
- Li, Bo LU ; Zhang, Dayuan ; Yao, Mingfa and Li, Zhongshan LU
- organization
- publishing date
- 2017
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- CH, Laser-induced fluorescence, Photofragmentation, Single-shot imaging, Turbulent methane/air flames
- in
- Proceedings of the Combustion Institute
- pages
- 4487 - 4495
- publisher
- Elsevier
- external identifiers
-
- wos:000393412600130
- scopus:85008683497
- ISSN
- 1540-7489
- DOI
- 10.1016/j.proci.2016.07.082
- language
- English
- LU publication?
- yes
- id
- 8c6d59f9-459d-4611-8ed2-75c3b0b6cf5d
- date added to LUP
- 2017-02-17 12:35:21
- date last changed
- 2025-01-20 09:07:06
@article{8c6d59f9-459d-4611-8ed2-75c3b0b6cf5d, abstract = {{<p>Single-shot imaging of methyl radical (CH<sub>3</sub>) in premixed methane/air flames is demonstrated using photofragmentation laser-induced fluorescence (PF-LIF) technique. A pump-probe strategy was adopted with the pump laser at 212.8 nm photolyzing CH<sub>3</sub>, and with the probe laser at 426.8 nm detecting the photolyzed CH (X <sup>2</sup>Π) fragments. Spatially resolved spectrograph of the PF-LIF signal from a stable laminar flame was recorded across the reaction zone to investigate potential interferences. The results indicate that the single-photon channel, CH<sub>3</sub> + 212.8 nm → CH (X <sup>2</sup>Π) + H<sub>2</sub>, dominates the photofragmentation process. The CH<sub>2</sub> radical was excluded from being an interfering precursor of the CH (X <sup>2</sup>Π) fragments owing to its relatively low concentration and small absorption cross section. Naturally present CH in the flame was identified as the main interference, but was conservatively estimated to account for only less than 4% of the total PF-LIF signal. Signal-to-noise ratio of around 10 was realized for single-shot imaging of natural CH<sub>3</sub> in turbulent jet flames.</p>}}, author = {{Li, Bo and Zhang, Dayuan and Yao, Mingfa and Li, Zhongshan}}, issn = {{1540-7489}}, keywords = {{CH; Laser-induced fluorescence; Photofragmentation; Single-shot imaging; Turbulent methane/air flames}}, language = {{eng}}, pages = {{4487--4495}}, publisher = {{Elsevier}}, series = {{Proceedings of the Combustion Institute}}, title = {{Strategy for single-shot CH<sub>3</sub> imaging in premixed methane/air flames using photofragmentation laser-induced fluorescence}}, url = {{http://dx.doi.org/10.1016/j.proci.2016.07.082}}, doi = {{10.1016/j.proci.2016.07.082}}, year = {{2017}}, }