Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners
Microscale hydrogen (H2) combustion is one of the promising technologies for renewable miniaturized heat sources. This study analyzes the oxygen combustion of H2 in small-scale counterflow burners, with carbon dioxide (CO2) added for safe hydrogen treatment (flame visualization and reduction of flam...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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The Japan Society of Mechanical Engineers
2022-04-01
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| Series: | Journal of Thermal Science and Technology |
| Subjects: | |
| Online Access: | https://www.jstage.jst.go.jp/article/jtst/17/1/17_22-00012/_pdf/-char/en |
| _version_ | 1818532736811401216 |
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| author | Daisuke SATO Shuta NAKACHI Kaito HONDA Keisuke OBU Toshiyuki KATSUMI Satoshi KADOWAKI |
| author_facet | Daisuke SATO Shuta NAKACHI Kaito HONDA Keisuke OBU Toshiyuki KATSUMI Satoshi KADOWAKI |
| author_sort | Daisuke SATO |
| collection | DOAJ |
| description | Microscale hydrogen (H2) combustion is one of the promising technologies for renewable miniaturized heat sources. This study analyzes the oxygen combustion of H2 in small-scale counterflow burners, with carbon dioxide (CO2) added for safe hydrogen treatment (flame visualization and reduction of flame propagation velocity). The effects of burner inner diameter, burner gap, and gas flow rate on the flame shape/size (thickness and diameter) are measured through flame image analysis. The experimental results show that the flame thickness and diameter monotonically decrease with a decrease in the burner inner diameter, burner gap, and H2 flow rate. The flame thickness decreases with an increase in the flame stretch rate, and the approximate curve representing this relationship varies depending on the burner inner diameter and H2 flow rate. Accordingly, the flame thickness normalized by H2 flow velocity and burner inner diameter is newly proposed, which strongly correlates with the flame stretch rate and converges on a single line, i.e., inverse of the square root of the flame stretch rate. These findings are also applicable to biogas (CH4-CO2 mixture)-O2 micro counterflow diffusion flames with the same CO2 concentration in the fuel gas and apparent equivalence ratio. |
| first_indexed | 2024-12-11T17:49:25Z |
| format | Article |
| id | doaj.art-ae56922b9e2a4f5097d544b26fbd24e3 |
| institution | Directory Open Access Journal |
| issn | 1880-5566 |
| language | English |
| last_indexed | 2024-12-11T17:49:25Z |
| publishDate | 2022-04-01 |
| publisher | The Japan Society of Mechanical Engineers |
| record_format | Article |
| series | Journal of Thermal Science and Technology |
| spelling | doaj.art-ae56922b9e2a4f5097d544b26fbd24e32022-12-22T00:56:16ZengThe Japan Society of Mechanical EngineersJournal of Thermal Science and Technology1880-55662022-04-0117122-0001222-0001210.1299/jtst.22-00012jtstExperimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burnersDaisuke SATO0Shuta NAKACHI1Kaito HONDA2Keisuke OBU3Toshiyuki KATSUMI4Satoshi KADOWAKI5Department of System Safety Engineering, Nagaoka University of TechnologyDepartment of Mechanical Engineering, Nagaoka University of TechnologyDepartment of Mechanical Engineering, Nagaoka University of TechnologyDepartment of Mechanical Engineering, Nagaoka University of TechnologyDepartment of Mechanical Engineering, Nagaoka University of TechnologyDepartment of System Safety Engineering, Nagaoka University of TechnologyMicroscale hydrogen (H2) combustion is one of the promising technologies for renewable miniaturized heat sources. This study analyzes the oxygen combustion of H2 in small-scale counterflow burners, with carbon dioxide (CO2) added for safe hydrogen treatment (flame visualization and reduction of flame propagation velocity). The effects of burner inner diameter, burner gap, and gas flow rate on the flame shape/size (thickness and diameter) are measured through flame image analysis. The experimental results show that the flame thickness and diameter monotonically decrease with a decrease in the burner inner diameter, burner gap, and H2 flow rate. The flame thickness decreases with an increase in the flame stretch rate, and the approximate curve representing this relationship varies depending on the burner inner diameter and H2 flow rate. Accordingly, the flame thickness normalized by H2 flow velocity and burner inner diameter is newly proposed, which strongly correlates with the flame stretch rate and converges on a single line, i.e., inverse of the square root of the flame stretch rate. These findings are also applicable to biogas (CH4-CO2 mixture)-O2 micro counterflow diffusion flames with the same CO2 concentration in the fuel gas and apparent equivalence ratio.https://www.jstage.jst.go.jp/article/jtst/17/1/17_22-00012/_pdf/-char/enhydrogen combustionoxygen-enriched combustionmicro diffusion flamecounterflow burnercarbon-dioxide additionflame stretch ratebiogas |
| spellingShingle | Daisuke SATO Shuta NAKACHI Kaito HONDA Keisuke OBU Toshiyuki KATSUMI Satoshi KADOWAKI Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners Journal of Thermal Science and Technology hydrogen combustion oxygen-enriched combustion micro diffusion flame counterflow burner carbon-dioxide addition flame stretch rate biogas |
| title | Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners |
| title_full | Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners |
| title_fullStr | Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners |
| title_full_unstemmed | Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners |
| title_short | Experimental analysis on micro diffusion flames formed by oxygen combustion of H2-CO2 mixture using counterflow burners |
| title_sort | experimental analysis on micro diffusion flames formed by oxygen combustion of h2 co2 mixture using counterflow burners |
| topic | hydrogen combustion oxygen-enriched combustion micro diffusion flame counterflow burner carbon-dioxide addition flame stretch rate biogas |
| url | https://www.jstage.jst.go.jp/article/jtst/17/1/17_22-00012/_pdf/-char/en |
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