Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners
Recent studies have demonstrated that ammonia is an emerging energy vector for the distribution of hydrogen from stranded sources. However, there are still many unknown parameters that need to be understood before ammonia can be a substantial substitute in fuelling current power generation systems....
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-10-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/14/20/6624 |
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| author | Marco Osvaldo Vigueras-Zúñiga Maria Elena Tejeda-del-Cueto Syed Mashruk Marina Kovaleva Cesar Leonardo Ordóñez-Romero Agustin Valera-Medina |
| author_facet | Marco Osvaldo Vigueras-Zúñiga Maria Elena Tejeda-del-Cueto Syed Mashruk Marina Kovaleva Cesar Leonardo Ordóñez-Romero Agustin Valera-Medina |
| author_sort | Marco Osvaldo Vigueras-Zúñiga |
| collection | DOAJ |
| description | Recent studies have demonstrated that ammonia is an emerging energy vector for the distribution of hydrogen from stranded sources. However, there are still many unknown parameters that need to be understood before ammonia can be a substantial substitute in fuelling current power generation systems. Therefore, current attempts have mainly utilised ammonia as a substitute for natural gas (mainly composed of methane) to mitigate the carbon footprint of the latter. Co-firing of ammonia/methane is likely to occur in the transition of replacing carbonaceous fuels with zero-carbo options. Hence, a better understanding of the combustion performance, flame features, and radical formation of ammonia/methane blends is required to address the challenges that these fuel combinations will bring. This study involves an experimental approach in combination with numerical modelling to elucidate the changes in radical formation across ammonia/methane flames at various concentrations. Radicals such as OH*, CH*, NH*, and NH<sub>2</sub>* are characterised via chemiluminescence whilst OH, CH, NH, and NH<sub>2</sub> are described via RANS κ-ω SST complex chemistry modelling. The results show a clear progression of radicals across flames, with higher ammonia fraction blends showing flames with more retreated shape distribution of CH* and NH* radicals in combination with more spread distribution of OH*. Simultaneously, equivalence ratio is a key parameter in defining the flame features, especially for production of NH<sub>2</sub>*. Since NH<sub>2</sub>* distribution is dependent on the equivalence ratio, CFD modelling was conducted at a constant equivalence ratio to enable the comparison between different blends. The results denote the good qualitative resemblance between models and chemiluminescence experiments, whilst it was recognised that for ammonia/methane blends the combined use of OH, CH, and NH<sub>2</sub> radicals is essential for defining the heat release rate of these flames. |
| first_indexed | 2024-03-10T06:35:16Z |
| format | Article |
| id | doaj.art-07ecf5d794ce4e1a97279f9517ee1b7e |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T06:35:16Z |
| publishDate | 2021-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-07ecf5d794ce4e1a97279f9517ee1b7e2023-11-22T18:06:08ZengMDPI AGEnergies1996-10732021-10-011420662410.3390/en14206624Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl BurnersMarco Osvaldo Vigueras-Zúñiga0Maria Elena Tejeda-del-Cueto1Syed Mashruk2Marina Kovaleva3Cesar Leonardo Ordóñez-Romero4Agustin Valera-Medina5School of Engineering, Universidad Veracruzana, Veracruz 94294, MexicoSchool of Engineering, Universidad Veracruzana, Veracruz 94294, MexicoCollege of Physical Sciences and Engineering, Cardiff University, Cardiff CF243AA, UKCollege of Physical Sciences and Engineering, Cardiff University, Cardiff CF243AA, UKInstituto de Física, Universidad Nacional Autónoma de México, Ciudad de México 04510, MexicoCollege of Physical Sciences and Engineering, Cardiff University, Cardiff CF243AA, UKRecent studies have demonstrated that ammonia is an emerging energy vector for the distribution of hydrogen from stranded sources. However, there are still many unknown parameters that need to be understood before ammonia can be a substantial substitute in fuelling current power generation systems. Therefore, current attempts have mainly utilised ammonia as a substitute for natural gas (mainly composed of methane) to mitigate the carbon footprint of the latter. Co-firing of ammonia/methane is likely to occur in the transition of replacing carbonaceous fuels with zero-carbo options. Hence, a better understanding of the combustion performance, flame features, and radical formation of ammonia/methane blends is required to address the challenges that these fuel combinations will bring. This study involves an experimental approach in combination with numerical modelling to elucidate the changes in radical formation across ammonia/methane flames at various concentrations. Radicals such as OH*, CH*, NH*, and NH<sub>2</sub>* are characterised via chemiluminescence whilst OH, CH, NH, and NH<sub>2</sub> are described via RANS κ-ω SST complex chemistry modelling. The results show a clear progression of radicals across flames, with higher ammonia fraction blends showing flames with more retreated shape distribution of CH* and NH* radicals in combination with more spread distribution of OH*. Simultaneously, equivalence ratio is a key parameter in defining the flame features, especially for production of NH<sub>2</sub>*. Since NH<sub>2</sub>* distribution is dependent on the equivalence ratio, CFD modelling was conducted at a constant equivalence ratio to enable the comparison between different blends. The results denote the good qualitative resemblance between models and chemiluminescence experiments, whilst it was recognised that for ammonia/methane blends the combined use of OH, CH, and NH<sub>2</sub> radicals is essential for defining the heat release rate of these flames.https://www.mdpi.com/1996-1073/14/20/6624ammoniahydrogencombustionmethaneradicalschemiluminescence |
| spellingShingle | Marco Osvaldo Vigueras-Zúñiga Maria Elena Tejeda-del-Cueto Syed Mashruk Marina Kovaleva Cesar Leonardo Ordóñez-Romero Agustin Valera-Medina Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners Energies ammonia hydrogen combustion methane radicals chemiluminescence |
| title | Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners |
| title_full | Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners |
| title_fullStr | Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners |
| title_full_unstemmed | Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners |
| title_short | Methane/Ammonia Radical Formation during High Temperature Reactions in Swirl Burners |
| title_sort | methane ammonia radical formation during high temperature reactions in swirl burners |
| topic | ammonia hydrogen combustion methane radicals chemiluminescence |
| url | https://www.mdpi.com/1996-1073/14/20/6624 |
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