Effect of Swirl Structure on Flame Stability in Pulverized-Coal Ammonia Co-Firing and Ammonia Sole-Firing under Load Variation

Jinheon Choi; Tae-Young Mun; Jaewon Chung; Hookyung Lee

doi:10.15231/jksc.2025.30.4.058

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2025 Vol.30, Issue 4 Preview Page

Research Article

Effect of Swirl Structure on Flame Stability in Pulverized-Coal Ammonia Co-Firing and Ammonia Sole-Firing under Load Variation 미분탄-암모니아 혼소 및 암모니아 전소 부하 변화 시 스월 구조에 따른 화염 안정성 평가

31 December 2025. pp. 58-71

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Abstract

Ammonia-coal co-firing can reduce CO₂ emissions in pulverized-coal boilers, but ammonia’s low burning velocity makes flame stabilization a key design issue. This study investigates the impact of swirler geometry on flame stability in a lab-scale pulverized coal-ammonia burner. Six tangential swirlers, combining three port numbers (8, 6, 4) and two axial positions (upper: U, lower: D), were tested over 1-5 kW_th. Flame imaging and two-color pyrometry quantified apparent flame intensity and coal particle temperature, and non-reacting CFD clarified the internal recirculation and turbulence fields. The 8-port cases (U-8, D-8) secured the widest stable operating range, whereas 4-port swirlers exhibited frequent ignition failure and blow-off at low loads. D-type geometries enhanced stability by promoting recirculation of coal reaction heat into the flame root. These results provide practical design guidelines for stabilizing ammonia-coal co-firing burners.

Keywords

Coal

Ammonia

Swirler geometry

Flame stability

Turbulent mixing

Load variation

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Information

Publisher :The Korean Society of Combustion
Publisher(Ko) :한국연소학회
Journal Title :Journal of the Korean Society of Combustion
Journal Title(Ko) :한국연소학회지
Volume : 30
No :4
Pages :58-71
Received Date : 2025-11-19
Revised Date : 2025-12-09
Accepted Date : 2025-12-09
DOI :https://doi.org/10.15231/jksc.2025.30.4.058

Journal of the Korean Society of Combustion ISSN:1226-0959(Print) 2466-2089(Online) 한국연소학회지

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