CIESC Journal ›› 2023, Vol. 74 ›› Issue (11): 4710-4719.DOI: 10.11949/0438-1157.20230989

• Energy and environmental engineering • Previous Articles     Next Articles

Spectral radiation characterization of OH*, NH2* and NH* in ammonia/methane diffusion flame

Zhengqiao DUAN(), Yan GONG, Qinghua GUO(), Guangsuo YU   

  1. Institute of Clean Coal Technology, East China University of Science and Technology, Shanghai 200237, China
  • Received:2023-09-21 Revised:2023-11-27 Online:2024-01-22 Published:2023-11-25
  • Contact: Qinghua GUO

氨/甲烷扩散火焰中OH*、NH2*和NH*光谱辐射特性研究

段正巧(), 龚岩, 郭庆华(), 于广锁   

  1. 华东理工大学洁净煤技术研究所,上海 200237
  • 通讯作者: 郭庆华
  • 作者简介:段正巧(1997—),男,硕士研究生,Y30211052@mail.ecust.edu.cn
  • 基金资助:
    国家自然科学基金项目(22178112)

Abstract:

Based on the flame spectroscopy diagnostic platform, a spectral imaging system was utilized to obtain the OH*, NH2* and NH* radiation distributions of the ammonia/methane diffusion flame. The reaction mechanism was explored in the CHEMKIN. The results show that compared with pure methane combustion, the OH* radiation distribution zone and radiation intensity of the flame after ammonia blending are significantly reduced, and the distribution pattern extends outwards downstream of the flame. With the increase of ammonia blending ratio, the radiation distribution zone of NH2* was raised to the downstream of the flame, and the radiation intensity increased. NH* radiation distribution zone was basically unchanged. The radiation intensity of NH* increased and then decreased with the increase of ammonia blending ratio. NH* radiation intensity reached the maximum when the ammonia fraction was from 0.2 to 0.3. The radiative intensity of the three radicals increased with the equivalence ratios, in which the distribution of OH* was biased toward the oxidant side, while NH2* and NH* were biased toward the fuel side. With the addition of NH2* and NH* reaction mechanisms, the simulation show that the main source of NH2* was the dehydrogenation process of ammonia. The changes in the ammonia blending ratio directly affected the generation of NH2*. The maximum production reaction of NH* indicated that the rate of the reaction generation of NH* was affected by the mixing ratio of ammonia and methane.

Key words: ammonia, methane, diffused, radicals, spectral radiation

摘要:

基于火焰光谱诊断平台,利用光谱成像系统获得氨/甲烷扩散火焰的OH*、NH2*和NH*辐射分布,并结合CHEMKIN探究其反应机理。结果表明:与纯甲烷燃烧相比,氨掺混后火焰的OH*辐射分布区域和辐射强度均降低较明显,在火焰下游分布形态向外延展。随着氨掺混比例的增加,NH2*辐射分布区域向火焰下游拉升,辐射强度增加。NH*辐射分布区域基本不变,辐射强度随氨掺混比例的增加先增加后降低,在氨分数为0.2~0.3时达到最大。三个自由基辐射强度均随当量比增大而增加,其中OH*分布偏向氧化剂侧,NH2*和NH*偏向燃料侧。添加NH2*和NH*反应机理后,模拟结果显示,NH2*的主要来源为氨的脱氢过程,掺氨比例的变化直接影响NH2*的生成,NH*最大生成反应的反应生成率受氨和甲烷混合比例的影响。

关键词: 氨, 甲烷, 扩散, 自由基, 光谱辐射

CLC Number: