Investigation of flame characteristics and cooling effectiveness of jet-cooled wall flameholders in vitiated flow
(2022) In Aerospace Science and Technology 127.- Abstract
Experimental and numerical studies were performed to understand the flame characteristics and cooling effect of jet-cooled wall flameholders in a simplified augmented combustor. The time-averaged flame structure and wall temperature were investigated employing an instantaneous flame capturing system with image processing technology and a wall temperature measurement system, respectively. Flow and fuel distribution simulations were carried out to analyze the flame structure and cooling effect of the jet-cooled flameholders in high-temperature and high-velocity vitiated flows. It was found that the jet cooling type and the cooling jet angle on the oblique plate α and on the rear plate β greatly affect the flame features and cooling effect... (More)
Experimental and numerical studies were performed to understand the flame characteristics and cooling effect of jet-cooled wall flameholders in a simplified augmented combustor. The time-averaged flame structure and wall temperature were investigated employing an instantaneous flame capturing system with image processing technology and a wall temperature measurement system, respectively. Flow and fuel distribution simulations were carried out to analyze the flame structure and cooling effect of the jet-cooled flameholders in high-temperature and high-velocity vitiated flows. It was found that the jet cooling type and the cooling jet angle on the oblique plate α and on the rear plate β greatly affect the flame features and cooling effect of the flameholder. The external-inhaled air cooling schemes can increase the flame luminosity and temperature and create a flame hollowed-out zone in the near-wall region to reduce flame radiation and heat convection, thereby achieving an excellent cooling effect. The pressure-driven gas jet cooling schemes yielded a weaker flame luminosity and its flame structure in the cavity more sensitive to the cooling jet angle than external-inhaled air cooling schemes. Moreover, the external-inhaled air cooling schemes have significantly better cooling effects than the pressure-driven gas jet cooling schemes under different mainstream conditions and fuel flow rates. Notably, the cooling schemes with α=30∘ and β=30∘ have more uniform wall temperature than that of α=90∘ and β=150∘ on the above two plates. Furthermore, the external-inhaled air cooling scheme with α=90∘ and β=150∘ has the best cooling performance under different mainstream and cooling air conditions and presents great cooling effectiveness in the case of enhancing cooling air temperature.
(Less)
- author
- Chen, Yuqian LU ; Fan, Yuxin ; Han, Qixiang and Bai, Xue Song LU
- organization
- publishing date
- 2022-08
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Cooling effectiveness, Flame characteristics, Fuel distribution, Jet cooling, Wall flameholder, Wall temperature
- in
- Aerospace Science and Technology
- volume
- 127
- article number
- 107710
- publisher
- Elsevier Masson SAS
- external identifiers
-
- scopus:85132503474
- ISSN
- 1270-9638
- DOI
- 10.1016/j.ast.2022.107710
- language
- English
- LU publication?
- yes
- id
- de94bbdb-2b03-4b38-9286-a6f82d1bbfa8
- date added to LUP
- 2022-09-05 15:00:11
- date last changed
- 2023-11-06 21:33:06
@article{de94bbdb-2b03-4b38-9286-a6f82d1bbfa8, abstract = {{<p>Experimental and numerical studies were performed to understand the flame characteristics and cooling effect of jet-cooled wall flameholders in a simplified augmented combustor. The time-averaged flame structure and wall temperature were investigated employing an instantaneous flame capturing system with image processing technology and a wall temperature measurement system, respectively. Flow and fuel distribution simulations were carried out to analyze the flame structure and cooling effect of the jet-cooled flameholders in high-temperature and high-velocity vitiated flows. It was found that the jet cooling type and the cooling jet angle on the oblique plate α and on the rear plate β greatly affect the flame features and cooling effect of the flameholder. The external-inhaled air cooling schemes can increase the flame luminosity and temperature and create a flame hollowed-out zone in the near-wall region to reduce flame radiation and heat convection, thereby achieving an excellent cooling effect. The pressure-driven gas jet cooling schemes yielded a weaker flame luminosity and its flame structure in the cavity more sensitive to the cooling jet angle than external-inhaled air cooling schemes. Moreover, the external-inhaled air cooling schemes have significantly better cooling effects than the pressure-driven gas jet cooling schemes under different mainstream conditions and fuel flow rates. Notably, the cooling schemes with α=30<sup>∘</sup> and β=30<sup>∘</sup> have more uniform wall temperature than that of α=90<sup>∘</sup> and β=150<sup>∘</sup> on the above two plates. Furthermore, the external-inhaled air cooling scheme with α=90<sup>∘</sup> and β=150<sup>∘</sup> has the best cooling performance under different mainstream and cooling air conditions and presents great cooling effectiveness in the case of enhancing cooling air temperature.</p>}}, author = {{Chen, Yuqian and Fan, Yuxin and Han, Qixiang and Bai, Xue Song}}, issn = {{1270-9638}}, keywords = {{Cooling effectiveness; Flame characteristics; Fuel distribution; Jet cooling; Wall flameholder; Wall temperature}}, language = {{eng}}, publisher = {{Elsevier Masson SAS}}, series = {{Aerospace Science and Technology}}, title = {{Investigation of flame characteristics and cooling effectiveness of jet-cooled wall flameholders in vitiated flow}}, url = {{http://dx.doi.org/10.1016/j.ast.2022.107710}}, doi = {{10.1016/j.ast.2022.107710}}, volume = {{127}}, year = {{2022}}, }