Propagation of Darrieus-Landau unstable laminar and turbulent expanding flames
(2021) In Proceedings of the Combustion Institute 38(2). p.2013-2021- Abstract
The propagation of laminar and turbulent expanding flames subjected to Darrieus-Landau (DL), hydrodynamic instability was experimentally studied by employing stoichiometric H2/O2/N2 flames under quiescent and turbulent conditions performed in a newly developed medium-scale, fan-stirred combustion chamber. In quiescent environment, DL unstable laminar flame exhibits three-stage propagation, i.e. smooth expansion, transition acceleration, and self-similar acceleration. The self-similar acceleration is characterized by a power-law growth of acceleration exponent, α, with normalized Peclet number, which is different from the usually suggested self-similar propagation with a constant α. The imposed turbulence... (More)
The propagation of laminar and turbulent expanding flames subjected to Darrieus-Landau (DL), hydrodynamic instability was experimentally studied by employing stoichiometric H2/O2/N2 flames under quiescent and turbulent conditions performed in a newly developed medium-scale, fan-stirred combustion chamber. In quiescent environment, DL unstable laminar flame exhibits three-stage propagation, i.e. smooth expansion, transition acceleration, and self-similar acceleration. The self-similar acceleration is characterized by a power-law growth of acceleration exponent, α, with normalized Peclet number, which is different from the usually suggested self-similar propagation with a constant α. The imposed turbulence advances the onset of both transition acceleration and self-similar acceleration stages and promotes the strength of flame acceleration as additional wrinkles are invoked by turbulence eddies. A DL-turbulent interaction regime is confirmed to be the classical corrugated flamelets regime. Furthermore, the DL instability significantly facilitates the propagation of expanding flames in medium and even intense turbulence. The development of DL cells is not suppressed by turbulence eddies, and it needs to be considered in turbulent combustion.
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- author
- Cai, Xiao LU ; Wang, Jinhua ; Bian, Zhijian ; Zhao, Haoran ; Li, Zhongshan LU and Huang, Zuohua
- organization
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Acceleration exponent, Darrieus-Landau instability, Flame propagation, Laminar and turbulent flames
- in
- Proceedings of the Combustion Institute
- volume
- 38
- issue
- 2
- pages
- 9 pages
- publisher
- Elsevier
- external identifiers
-
- scopus:85091042921
- ISSN
- 1540-7489
- DOI
- 10.1016/j.proci.2020.06.247
- language
- English
- LU publication?
- yes
- id
- 54b7ff36-cf8b-4540-8943-f054d702f663
- date added to LUP
- 2020-10-02 14:55:28
- date last changed
- 2022-04-19 01:00:34
@article{54b7ff36-cf8b-4540-8943-f054d702f663, abstract = {{<p>The propagation of laminar and turbulent expanding flames subjected to Darrieus-Landau (DL), hydrodynamic instability was experimentally studied by employing stoichiometric H<sub>2</sub>/O<sub>2</sub>/N<sub>2</sub> flames under quiescent and turbulent conditions performed in a newly developed medium-scale, fan-stirred combustion chamber. In quiescent environment, DL unstable laminar flame exhibits three-stage propagation, i.e. smooth expansion, transition acceleration, and self-similar acceleration. The self-similar acceleration is characterized by a power-law growth of acceleration exponent, α, with normalized Peclet number, which is different from the usually suggested self-similar propagation with a constant α. The imposed turbulence advances the onset of both transition acceleration and self-similar acceleration stages and promotes the strength of flame acceleration as additional wrinkles are invoked by turbulence eddies. A DL-turbulent interaction regime is confirmed to be the classical corrugated flamelets regime. Furthermore, the DL instability significantly facilitates the propagation of expanding flames in medium and even intense turbulence. The development of DL cells is not suppressed by turbulence eddies, and it needs to be considered in turbulent combustion.</p>}}, author = {{Cai, Xiao and Wang, Jinhua and Bian, Zhijian and Zhao, Haoran and Li, Zhongshan and Huang, Zuohua}}, issn = {{1540-7489}}, keywords = {{Acceleration exponent; Darrieus-Landau instability; Flame propagation; Laminar and turbulent flames}}, language = {{eng}}, number = {{2}}, pages = {{2013--2021}}, publisher = {{Elsevier}}, series = {{Proceedings of the Combustion Institute}}, title = {{Propagation of Darrieus-Landau unstable laminar and turbulent expanding flames}}, url = {{http://dx.doi.org/10.1016/j.proci.2020.06.247}}, doi = {{10.1016/j.proci.2020.06.247}}, volume = {{38}}, year = {{2021}}, }