Investigation of the flame stabilization mechanism of the hydrocarbon fuel in the supersonic combustor
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摘要: 在来流总温1085K、进口马赫数2.0下开展了煤油燃料超声速燃烧试验，使用高速摄像观测了火焰的形态和结构，采用平面激光诱导荧光技术（PLIF）观测了煤油和OH的分布，结合数值模拟结果分析了燃烧室的火焰稳定机制。测量结果显示：燃烧反应主要发生在射流的下游区域和凹槽区域内，随着燃料当量比的增加，火焰传播角度及火焰向主流的穿透高度增加。数值模拟结果与实验测量吻合较好。火焰稳定机制分析显示：液态煤油喷入燃烧室内，主要分布在下壁面附近的流场中，燃烧产生的高温燃烧产物通过凹槽剪切层与回流区之间的相互作用，进入凹槽并为剪切层中的空气-煤油混合气体提供稳定的热量和中间产物，使得火焰基底能够稳定在剪切层内，并以相对固定的角度向主流流场中传播。Abstract: Supersonic kerosene combustion experiments were conducted at stagnation temperature of 1085K and inlet Mach number of 2.0. High speed camera was applied to observe the shape and structure of the flame. PLIF was used to observe the distributions of kerosene and OH. Flame stabilization mechanism was analyzed with the combination of numerical and experimental results. The experimental results show that the combustion reaction occurs in the downstream of the jet stream and in the cavity region. The spread angle and the penetration height of the flame are increased with the increase of the equivalence ratio. Numerical simulations show a reasonable agreement with the experimental results. The flame stabilization mechanism analysis indicates that the kerosene fuel is mostly distributed in the region near the floor after injected into the combustor in the liquid state. Combustion product with high temperature was transported into the cavity through the interaction between the cavity shear layer and the circulation. This process provides heat and radicals to the mixture of air-kerosene in the shear layer. Hence, the flame base is able to be stabilized in the shear layer and spread to the mainstream at a constant angle.
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图 1 甲烷燃烧加热直连式燃烧室试验系统示意图
Figure 1. Schematic of the methane heater direct connected combustor test system
图 2 双模态单凹槽超声速燃烧室试验模型示意图
Figure 2. Schematic of the dual-mode cavity-based supersonic combustor model
图 5 ERk=0.33时的瞬时kerosene-PLIF图像
Figure 5. Instantaneous kerosene-PLIF images at ERk=0.33
图 6 ERk=0.33时的瞬时OH & kerosene-PLIF图像
Figure 6. Instantaneous OH & kerosene-PLIF images at ERk=0.33
图 10 燃烧室壁面压力计算值与试验值对比
Figure 10. Comparisons of the wall pressure distributions between calculation and experiment
图 11 ERk=0.33时燃烧室中心截面静温云图
Figure 11. Static pressure contour at spanwise centerline of the combustor in the case of ERk=0.33
图 12 ERk=0.33时燃烧室中心截面煤油摩尔分数云图
Figure 12. Kerosene mole fraction contour at spanwise centerline of the combustor in the case of ERk=0.33
图 13 ERk=0.33时燃烧室中心截面OH摩尔分数云图
Figure 13. OH mole fraction contour at spanwise centerline of the combustor in the case of ERk=0.33
图 14 ERk=0.33时燃烧室中心截面流线图
Figure 14. Streamline at spanwise centerline of the combustor in the case of ERk=0.33
图 15 不同工作状态的燃烧室流线图
Figure 15. Streamline at spanwise centerline of the combustor under different test conditions
图 16 燃烧室中心截面流线与燃烧可见光叠加
Figure 16. Combinations of the streamline and combustion luminosity at spanwise centerline of the combustor
图 17 燃烧室中心截面流线与平均PLIF荧光图像(ERk=0.18)
Figure 17. Combinations of the streamline and PLIF at spanwise centerline of the combustor in the case of ERk=0.18
图 18 燃烧室中心截面流线与平均PLIF图像(ERk=0.33)
Figure 18. Combinations of the streamline and PLIF at spanwise centerline of the combustor in the case of ERk=0.33
图 19 燃烧室中心截面流线与平均PLIF图像(ERk=0.41)
Figure 19. Combinations of the streamline and PLIF at spanwise centerline of the combustor in the case of ERk=0.41
表 1 实验状态
Table 1. Test conditions
燃烧室进口参数 燃料供应参数 总温
Tin*/K总压
pin*/MPa先锋氢气当量比
ERH煤油当量比
ERk0.065 0.18 1085±20 1.05±0.03 0.065 0.33 0.065 0.41 
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[1] Segal C. The scramjet engine:processes and characteristics[M]. New York:Cambridge University Press, 2009. [2] Barnes F W, Segal C. Cavity-based flameholding for chemically-reacting supersonic flows[J]. Progress in Aerospace Sciences, 2015, 76:24-41. doi: 10.1016/j.paerosci.2015.04.002 [3] Li X P, Liu W D, Pan Y, et al. Characterization of kerosene distribution around the ignition cavity in a scramjet combustor[J]. Acta Astronautica, 2017, 134:11-16. doi: 10.1016/j.actaastro.2017.01.037 [4] Li X P, Liu W D, Yang L C, et al. Experimental investigation on fuel distribution in a scramjet combustor with dual cavity[J]. Journal of Propulsion and Power, 2017, 34(2):1-5. doi: 10.2514/1.B36749 [5] Fotia M L. Experimental study of shock-train/combustion coupling and flame dynamics in a heated supersonic flow[D]. The University of Michigan, 2012. [6] Micka D J. Combustion stabilization, structure, and spreading in a laboratory dual-mode scramjet combustor[D]. The University of Michigan, 2010. http://www.researchgate.net/publication/44180935_Combustion_Stabilization_Structure_and_Spreading_in_a_Laboratory_Dual-Mode_Scramjet_Combustor [7] Micka D J, Torrez S M, Driscoll J F. Heat release distribution in a dual-mode scramjet combustor-measurements and modeling[R]. AIAA 2009-7362, 2009. [8] Micka D J, Driscoll J F. Combustion characteristics of a dual-mode scramjet combustor with cavity flameholder[J]. Proceedings of the Combustion Institute, 2009, 32(2):2397-2404. doi: 10.1016/j.proci.2008.06.192 [9] Wang H B, Wang Z G, Sun M B, et al. Combustion modes of hydrogen jet combustion in a cavity-based supersonic combustor[J]. International Journal of Hydrogen Energy, 2013, 38(27):12078-12089. doi: 10.1016/j.ijhydene.2013.06.132 [10] Le J L, Yang S H, Li H B, et al. Analysis and correlation of flame stability limits in supersonic flow with cavity flameholder[R]. AIAA 2012-5948, 2012. [11] Yuan Y M, Zhang T C, Yao W, et al. Study on flame stabilization in a dual-mode combustor using optical measurements[J]. Journal of Propulsion and Power, 2015, 31(6):1524-1531. doi: 10.2514/1.B35689 [12] Kundu K P, Penko P F, Yang S L. Reduced reaction mechanisms for numerical calculations in combustion of hydrocarbon fuels[R]. AIAA 98-0803, 1998. [13] Ben-Yakar A, Hanson R K. Cavity flame-holders for ignition and flame stabilization in scramjets:an overview[J]. Journal of Propulsion and Power, 2001, 17(4):869-877. doi: 10.2514/2.5818 -
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