Cargando…
A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing
The large eddy simulation method combined with the Eulerian stochastic field approach has been used to study excited lifted hydrogen flames in a stream of hot co-flow in a configuration closely corresponding to the so-called Cabra flame. The excitation is obtained by adding to an inlet velocity prof...
Autores principales: | , |
---|---|
Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2022
|
Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8854660/ https://www.ncbi.nlm.nih.gov/pubmed/35177738 http://dx.doi.org/10.1038/s41598-022-06740-4 |
_version_ | 1784653478519373824 |
---|---|
author | Tyliszczak, Artur Wawrzak, Agnieszka |
author_facet | Tyliszczak, Artur Wawrzak, Agnieszka |
author_sort | Tyliszczak, Artur |
collection | PubMed |
description | The large eddy simulation method combined with the Eulerian stochastic field approach has been used to study excited lifted hydrogen flames in a stream of hot co-flow in a configuration closely corresponding to the so-called Cabra flame. The excitation is obtained by adding to an inlet velocity profile three types of forcing [(1) axial; (2) flapping; (3) combination of both] with the amplitude of 15% of the fuel jet velocity and the frequency corresponding to the Strouhal numbers [Formula: see text] . It is shown that such a type of forcing significantly changes the lift-off height ([Formula: see text] ) of the flame and its global shape, resulting in the flame occupying a large volume or the flame, which transforms from the circular one into a quasi-planar one. Both the [Formula: see text] and size of the flames were found to be a function of the type of forcing and its frequency. The minimum value of [Formula: see text] has been found for the case when the axial and flapping forcing were combined and acted at the forcing frequency close to the preferred one in the non-excited configuration. The impact of the flapping forcing manifested through a widening of the flame in the flapping direction. It was shown that the excitation increases the level of temperature fluctuations caused by an intensified mixing process. The computational results are validated based on the solutions obtained for the non-excited flame for which experimental data are available. |
format | Online Article Text |
id | pubmed-8854660 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-88546602022-02-18 A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing Tyliszczak, Artur Wawrzak, Agnieszka Sci Rep Article The large eddy simulation method combined with the Eulerian stochastic field approach has been used to study excited lifted hydrogen flames in a stream of hot co-flow in a configuration closely corresponding to the so-called Cabra flame. The excitation is obtained by adding to an inlet velocity profile three types of forcing [(1) axial; (2) flapping; (3) combination of both] with the amplitude of 15% of the fuel jet velocity and the frequency corresponding to the Strouhal numbers [Formula: see text] . It is shown that such a type of forcing significantly changes the lift-off height ([Formula: see text] ) of the flame and its global shape, resulting in the flame occupying a large volume or the flame, which transforms from the circular one into a quasi-planar one. Both the [Formula: see text] and size of the flames were found to be a function of the type of forcing and its frequency. The minimum value of [Formula: see text] has been found for the case when the axial and flapping forcing were combined and acted at the forcing frequency close to the preferred one in the non-excited configuration. The impact of the flapping forcing manifested through a widening of the flame in the flapping direction. It was shown that the excitation increases the level of temperature fluctuations caused by an intensified mixing process. The computational results are validated based on the solutions obtained for the non-excited flame for which experimental data are available. Nature Publishing Group UK 2022-02-17 /pmc/articles/PMC8854660/ /pubmed/35177738 http://dx.doi.org/10.1038/s41598-022-06740-4 Text en © The Author(s) 2022 https://creativecommons.org/licenses/by/4.0/Open AccessThis article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/ (https://creativecommons.org/licenses/by/4.0/) . |
spellingShingle | Article Tyliszczak, Artur Wawrzak, Agnieszka A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title | A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title_full | A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title_fullStr | A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title_full_unstemmed | A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title_short | A numerical study of a lifted [Formula: see text] flame excited by an axial and flapping forcing |
title_sort | numerical study of a lifted [formula: see text] flame excited by an axial and flapping forcing |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8854660/ https://www.ncbi.nlm.nih.gov/pubmed/35177738 http://dx.doi.org/10.1038/s41598-022-06740-4 |
work_keys_str_mv | AT tyliszczakartur anumericalstudyofaliftedformulaseetextflameexcitedbyanaxialandflappingforcing AT wawrzakagnieszka anumericalstudyofaliftedformulaseetextflameexcitedbyanaxialandflappingforcing AT tyliszczakartur numericalstudyofaliftedformulaseetextflameexcitedbyanaxialandflappingforcing AT wawrzakagnieszka numericalstudyofaliftedformulaseetextflameexcitedbyanaxialandflappingforcing |