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摘要:
针对模型燃烧室中值班火焰的燃烧不稳定性问题，实验测量燃烧室内多点动态压力和火焰图像，利用快速傅里叶分析、本征正交分解(POD)等方法进行分析。结果表明：随着当量比增大，值班火焰的稳定性发生2次分岔现象，相应的不稳定模态分别对应系统的3阶、2阶本征纵向声学模态，均发生极限环振荡。POD结果表明：涡声频率锁定，发生在燃烧室纵向声学模态频率处，燃烧室内发生声-涡-火焰耦合的不稳定过程。而伴随着当量比提高，一方面，大尺度旋涡脱落改变火焰面积引发强烈放热振荡，声能产生增大；另一方面，两分支火焰张角不断增大，火焰位置主要波动方向与主要声学波动沿同一轴线。两方面作用下热声耦合更加容易，热释放脉动与压力脉动耦合的相位角减小，进而发生模态转换。
Abstract:To address he combustion instability of pilot flame in the model combustor, the multi-point dynamic pressure and flame images are experimentally measured in the combustor, and analyzed by means of fast Fourier analysis and proper orthogonal decomposition(POD). It is observed that with the increase of the equivalence ratio, two bifurcations occur with limit cycle oscillations, and the corresponding unstable modes correspond to the third-order and second-order intrinsic longitudinal acoustic modes of the system. The POD results show that the vortex-acoustic frequency lock-in occurs at the longitudinal acoustic mode frequency of the combustor, and the acoustic-vortex-flame coupling instability process occurs in the combustor. On the one hand, large-scale vortex shedding increases sound energy output by altering the flame area and producing severe oscillations in heat release with an increase in equivalency ratio. Conversely, as the angle between two flame branches increases, the main wave direction of the flame position is along the same axis as the main acoustic wave. The modal transition takes place when two factors come into play: the thermoacoustic coupling becomes easier, and the phase angle of the pressure pulsation and heat release pulsation coupling lowers.
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图 5 $ \phi $=0.042时相空间重构结果
Figure 5. Time-phase space reconstruction result at $ \phi $=0.042
图 6 $ \phi $=0.115时相空间重构结果
Figure 6. Time-phase space reconstruction result at $ \phi $=0.115
图 10 $ \phi $=0.042时前20阶POD模态能量比例
Figure 10. The first twenty POD modes energy proportion at $ \phi $=0.042
图 11 $ \phi $=0.042时前6阶POD模态空间分布结构
Figure 11. Spatial distribution structure of the first 6 POD modes at $ \phi $=0.042
图 12 $ \phi $=0.042的时间常数频谱分析
Figure 12. Spectral analysis of time constant at $ \phi $=0.042
图 13 $ \phi $=0.084时前20阶POD模态能量比例
Figure 13. The first twenty POD modes energy proportion at $ \phi $=0.084
图 14 $ \phi $=0.084时前6阶POD模态空间分布结构
Figure 14. Spatial distribution structure of the first six POD modes at $ \phi $=0.084
图 15 $ \phi $=0.084的时间常数频谱分析
Figure 15. Spectral analysis of time constant at $ \phi $=0.084
图 16 $ \phi $=0.115时前20阶POD模态能量比例
Figure 16. The first twenty POD modes energy proportion at $ \phi $=0.115
图 17 $ \phi $=0.115时前6阶POD模态空间分布结构
Figure 17. Spatial distribution structure of the first six POD modes at $ \phi $=0.115
图 18 $ \phi $=0.115的时间常数频谱分析
Figure 18. Spectral analysis of time constant at $ \phi $=0.115
图 19 $ \phi $=0.042时火焰周期动态过程
Figure 19. Dynamic process of flame cycle at $ \phi $=0.042
图 20 $ \phi $=0.084时火焰周期动态过程
Figure 20. Dynamic process of flame cycle at $ \phi $=0.084
图 21 $ \phi $=0.084时5.5 ms时刻火焰局部放大图
Figure 21. Local magnification of flame at moment of 5.5 ms at $ \phi $=0.084
图 22 $ \phi $=0.115时火焰周期动态过程
Figure 22. Dynamic process of flame cycle at $ \phi $=0.115
图 23 $ \phi $=0.115时5.5 ms时刻火焰局部放大图
Figure 23. Local magnification of flame at moment of 5.5 ms at $ \phi $=0.115
表 1 实验工况参数
Table 1. Experimental working condition parameters
工况 燃料质量流量/(g·s−1) 空气质量流量/(g·s−1) 当量比$ \phi $ 1 0.179 98 0.031 2 0.238 98 0.042 3 0.298 98 0.052 4 0.357 98 0.063 5 0.417 98 0.073 6 0.476 98 0.084 7 0.536 98 0.094 8 0.596 98 0.105 9 0.655 98 0.115 10 0.715 98 0.125 11 0.774 98 0.136 
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[1] 金莉, 谭永华. 火焰稳定器综述[J]. 火箭推进, 2006, 32(1): 30-34.JIN L, TAN Y H. Review of flame stabilizer[J]. Journal of Rocket Propulsion, 2006, 32(1): 30-34 (in Chinese). [2] LOVETT J, BROGAN T, PHILIPPONA D, et al. Development needs for advanced afterburner designs[C]//Proceedings of the 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference &Exhibit. Reston: AIAA, 2004: 4192. [3] LIEUWEN T C, YANG V. Combustion instabilities in gas turbine engines: Operational experience, fundamental mechanisms, and modeling[M]. Reston: American Institute of Aeronautics and Astronautics, 2005: 4. [4] HAN X, LAERA D, MORGANS A S, et al. Inlet temperature driven supercritical bifurcation of combustion instabilities in a lean premixed prevaporized combustor[J]. Experimental Thermal and Fluid Science, 2019: 109: 109857. [5] SHANBHOGUE S J, HUSAIN S, LIEUWEN T. Lean blowoff of bluff body stabilized flames: Scaling and dynamics[J]. Progress in Energy and Combustion Science, 2009, 35(1): 98-120. doi: 10.1016/j.pecs.2008.07.003 [6] TUTTLE S G, CHAUDHURI S, KOPP-VAUGHAN K M, et al. Lean blowoff behavior of asymmetrically-fueled bluff body-stabilized flames[J]. Combustion and Flame, 2013, 160(9): 1677-1692. [7] LUBARSKY E, CROSS C, FRICKER A, et al. Dynamics of V-gutter-stabilized Jet-A flames in a single flame holder combustor with full optical accesss[C]//Proceedings of the 45th AIAA/ASME/SAE/ASEE Joint Propulsion Conference &Exhibit. Reston: AIAA, 2009: 5291. [8] POINSOT T J, TROUVE A C, VEYNANTE D P, et al. Vortex-driven acoustically coupled combustion instabilities[J]. Journal of Fluid Mechanics. 2006, 177: 265-292. [9] PILLAI A L, NAGAO J, AWANE R, et al. Influences of liquid fuel atomization and flow rate fluctuations on spray combustion instabilities in a backward-facing step combustor[J]. Combustion and Flame, 2020, 220: 337-356. doi: 10.1016/j.combustflame.2020.06.031 [10] LIU W J, WANG H, YANG Q, et al. Flow dynamics in a multiswirler model combustor based on large eddy simulation and proper orthogonal decomposition analysis[J]. Journal of Engineering for Gas Turbines and Power, 2019, 141(12): 121014. [11] LIU W J, XUE R, ZHANG L, et al. Nonlinear response of a premixed low-swirl flame to acoustic excitation with large amplitude[J]. Combustion and Flame, 2022, 235: 2180. [12] KIM K T, LEE J G, QUAY B D, et al. Response of partially premixed flames to acoustic velocity and equivalence ratio perturbations[J]. Combustion and Flame, 2010, 157: 1731-1744. doi: 10.1016/j.combustflame.2010.04.006 [13] SHANBHOGUE S, SHIN D H, HEMCHANDRA S, et al. Flame sheet dynamics of bluff-body stabilized flames during longitudinal acoustic forcing[J]. Proceedings of the Combustion Institute. 2009, 32(2): 1787-1794. [14] BENJAMIN A B, SATHESH M. Lock-in phenomenon of vortex shedding in flows excited with two commensurate frequencies: A theoretical investigation pertaining to combustion instability[J]. Journal of Fluid Mechanics, 2021, 925(409): 9. [15] EMERSON B, MONDRAGON U, ACHARYA V, et al. Velocity and flame wrinkling characteristics of a transversely forced, bluff-body stabilized flame, Part Ⅰ: Experiments and data analysis[J]. Combustion Science and Technology, 2013, 185: 1056-1076. [16] LI H G, SUNG H, YANG V. Large eddy simulation of combustion dynamics of bluff body stabilized flame[C]//Proceedings of the 49th AIAA Aerospace Sciences Meeting including the New Horizons Forum and Aerospace Exposition. Reston: AIAA, 2011: 783. [17] EMERSON B, LIEUWEN T. Dynamics of harmonically excited, reacting bluff body wakes near the global hydrodynamic stability boundary[J]. Journal of Fluid Mechanics, 2015, 779: 716-750. [18] AHN M, LIM D, KIM T, et al. Pinch-off process of Burke–Schumann flame under acoustic excitation[J]. Combustion and Flame, 2021, 231: 111478-111488. doi: 10.1016/j.combustflame.2021.111478 [19] FUGGER C A, CASWELL A W. The influence of spanwise nonuniformity on lean blowoff in bluff body stabilized turbulent premixed flames[J]. Proceedings of the Combustion Institute, 2021, 38(4): 6327-6335. doi: 10.1016/j.proci.2020.06.145 [20] KOSTKA S, LYNCH A C, HUELSKAMP B C, et al. Characterization of flame-shedding behavior behind a bluff-body using proper orthogonal decomposition[J]. Combustion and Flame, 2012, 159(9): 2872-2882. doi: 10.1016/j.combustflame.2012.03.021 [21] RICHARDS A, JANUS M C. Characterization of oscillations during premix gas turbine combustion[J]. Journal of Engineering for Gas Turbines and Power, 1998, 120(2): 294-302. doi: 10.1115/1.2818120 [22] 王欣尧, 韩啸, 林宇震, 等. 中心分级旋流火焰中热声不稳定分岔现象研究[J]. 燃烧科学与技术, 2021, 27(4): 382-387.WANG X Y, HAN X, LIN Y Z, et al. Research on thermoacoustic instability bifurcation phenomenon in centrally graded swirling flames[J]. Combustion Science and Technology, 2021, 27(4): 382-387(in Chinese). [23] LI J X, MORGANS A S. Time domain simulations of nonlinear thermoacoustic behaviour in a simple combustor using a wave-based approach[J]. Journal of Sound and Vibration, 2015, 346: 345-360. doi: 10.1016/j.jsv.2015.01.032 [24] TAKENS F. Detecting strange attractors in turbulence[C]//Dynamic Systems and Turbulence, Warwick 1980. Berlin: Springer, 1981: 366-381. [25] 葛逸飞, 李森, 魏小林. 利用相空间重构方法分析层流扩散火焰燃烧不稳定现象[J]. 工程热物理学报, 2020, 41(6): 1550-1555.GE Y F, LI S, WEI X L. An analysis of laminar co-flow diffusion flame inatability based on phase space reconstruction method[J]. Journal of Engineering Thermophysics, 2020, 41(6): 1550-1555(in Chinese). [26] FU X, YANG F J, GUO Z H. Combustion instability of pilot flame in a pilot bluff body stabilized combustor[J]. Chinese Journal of Aeronautics, 2015, 28(6): 1606-1615. [27] CHAUDHURI S, KOSTKA S, TUTTLE S G, et al. Blowoff mechanism of two dimensional bluff-body stabilized turbulent premixed flames in a prototypical combustor[J]. Combustion and Flame, 2011, 158(7): 1358-1371. doi: 10.1016/j.combustflame.2010.11.012 [28] SINGH G, MARIAPPAN S. Experimental investigation on the route to vortex-acoustic lock-in phenomenon in bluff body stabilized combustors[J]. Combustion Science and Technology, 2019, 193: 1538-1566. [29] HARDI J S, ZACH HALLUM W, HUANG C, et al. Approaches for comparing numerical simulation of combustion instability and flame imaging[J]. Journal of Propulsion and Power, 2016, 32: 279-294. doi: 10.2514/1.B35780 -
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