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Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

Experimental Study of Transient Mechanisms of Bistable Flame Shape Transitions in a Swirl Combustor

[+] Author and Article Information
Michael Stöhr

German Aerospace Center (DLR),
Institute of Combustion Technology,
Pfaffenwaldring 38-40,
Stuttgart 70569, Germany
e-mail: michael.stoehr@dlr.de

Kilian Oberleithner

Chair of Fluid Dynamics,
Hermann-Föttinger-Institut,
Technische Universität Berlin,
Müller-Breslau-Str. 8,
Berlin 10623, Germany
e-mail: oberleithner@tu-berlin.de

Moritz Sieber

Chair of Fluid Dynamics,
Hermann-Föttinger-Institut,
Technische Universität Berlin,
Müller-Breslau-Str. 8,
Berlin 10623, Germany
e-mail: moritz.sieber@tu-berlin.de

Zhiyao Yin

German Aerospace Center (DLR),
Institute of Combustion Technology,
Pfaffenwaldring 38-40,
Stuttgart 70569, Germany
e-mail: zhiyao.yin@dlr.de

Wolfgang Meier

German Aerospace Center (DLR),
Institute of Combustion Technology,
Pfaffenwaldring 38-40,
Stuttgart 70569, Germany
e-mail: wolfgang.meier@dlr.de

1Corresponding author.

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received July 7, 2017; final manuscript received July 11, 2017; published online September 19, 2017. Editor: David Wisler.

J. Eng. Gas Turbines Power 140(1), 011503 (Sep 19, 2017) (8 pages) Paper No: GTP-17-1315; doi: 10.1115/1.4037724 History: Received July 07, 2017; Revised July 11, 2017

Sudden changes of flame shape are an undesired, yet poorly understood feature of swirl combustors used in gas turbines. The present work studies flame shape transition mechanisms of a bistable turbulent swirl flame in a gas turbine model combustor, which alternates intermittently between an attached V-form and a lifted M-form. Time-resolved velocity fields and two-dimensional flame structures were measured simultaneously using high-speed stereo-particle image velocimetry (PIV) and planar laser-induced fluorescence of OH (OH-PLIF) at 10 kHz. The data analysis is performed using two novel methods that are well adapted to the study of transient flame shape transitions: First, the linear stability analysis (LSA) of a time-varying mean flow and second, the recently proposed spectral proper orthogonal decomposition (SPOD). The results show that the transitions are governed by two types of instability, namely a hydrodynamic instability in the form of a precessing vortex core (PVC) and a thermoacoustic (TA) instability. The LSA shows that the V-M transition implies the transient formation of a PVC as the result of a self-amplification process. The V-M transition, on the other hand, is induced by the appearance of a TA instability that suppresses the PVC and thereby modifies the flowfield such that the flame re-attaches at the nozzle. In summary, these results provide novel insights into the complex interactions of TA and hydrodynamic instabilities that govern the shape of turbulent swirl-stabilized flames.

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References

Fritsche, D. , Füri, M. , and Boulouchos, K. , 2007, “ An Experimental Investigation of Thermoacoustic Instabilities in a Premixed Swirl-Stabilized Flame,” Combust. Flame, 151(1–2), pp. 29–36. [CrossRef]
Biagioli, F. , Güthe, F. , and Schuermans, B. , 2008, “ Combustion Dynamics Linked to Flame Behaviour in a Partially Premixed Swirled Industrial Burner,” Exp. Therm. Fluid Sci., 32(7), pp. 1344–1353. [CrossRef]
Tummers, M. , Hübner, A. , van Veen, E. , Hanjalic, K. , and van der Meer, T. , 2009, “ Hysteresis and Transition in Swirling Nonpremixed Flames,” Combust. Flame, 156(2), pp. 447–459. [CrossRef]
Renaud, A. , Ducruix, S. , Scouflaire, P. , and Zimmer, L. , 2015, “ Flame Shape Transition in a Swirl Stabilised Liquid Fueled Burner,” Proc. Combust. Inst., 35(3), pp. 3365–3372. [CrossRef]
Guiberti, T. , Durox, D. , Scouflaire, P. , and Schuller, T. , 2015, “ Impact of Heat Loss and Hydrogen Enrichment on the Shape of Confined Swirling Flames,” Proc. Combust. Inst., 35(2), pp. 1385–1392. [CrossRef]
Oberleithner, K. , Stöhr, M. , Seong, H. I. , Christoph, M. A. , and Steinberg, A. M. , 2015, “ Formation and Flame-Induced Suppression of the Precessing Vortex Core in a Swirl Combustor: Experiments and Linear Stability Analysis,” Combust. Flame, 162(8), pp. 3100–3114. [CrossRef]
Arndt, C. M. , Steinberg, A. M. , Boxx, I. G. , Meier, W. , and Aigner, M. , 2010, “ Flow-Field and Flame Dynamics of a Gas Turbine Model Combustor During Transition Between Thermo-Acoustically Stable and Unstable States,” ASME Paper No. GT2010-22830.
Hermeth, S. , Staffelbach, G. , Gicquel, L. Y. , Anisimov, V. , Cirigliano, C. , and Poinsot, T. , 2014, “ Bistable Swirled Flames and Influence on Flame Transfer Functions,” Combust. Flame, 161(1), pp. 184–196. [CrossRef]
An, Q. , Kwong, W. Y. , Geraedts, B. D. , and Steinberg, A. M. , 2016, “ Coupled Dynamics of Lift-Off and Precessing Vortex Core Formation in Swirl Flames,” Combust. Flame, 168, pp. 228–239. [CrossRef]
Selle, L. , Lartigue, G. , Poinsot, T. , Koch, R. , Schildmacher, K.-U. , Krebs, W. , Prade, B. , Kaufmann, P. , and Veynante, D. , 2004, “ Compressible Large Eddy Simulation of Turbulent Combustion in Complex Geometry on Unstructured Meshes,” Combust. Flame, 137(4), pp. 489–505. [CrossRef]
Freitag, M. , and Janicka, J. , 2007, “ Investigation of a Strongly Swirled Unconfined Premixed Flame Using LES,” Proc. Combust. Inst., 31(1), pp. 1477–1485. [CrossRef]
De, A. , Zhu, S. , and Acharya, S. , 2010, “ An Experimental and Computational Study of a Swirl-Stabilized Premixed Flame,” ASME J. Eng. Gas Turbines Power, 132(7), p. 071503. [CrossRef]
Stöhr, M. , Yin, Z. , and Meier, W. , 2016, “ Interaction Between Velocity Fluctuations and Equivalence Ratio Fluctuations During Thermoacoustic Oscillations in a Partially Premixed Swirl Combustor,” Proc. Combust. Inst., 36(3), pp. 3907–3915. [CrossRef]
Sieber, M. , Paschereit, C. O. , and Oberleithner, K. , 2016, “ Spectral Proper Orthogonal Decomposition,” J. Fluid Mech., 792(4), pp. 798–828. [CrossRef]
Holmes, P. , Lumley, J. , and Berkooz, G. , 1998, Turbulence, Coherent Structures, Dynamical Systems and Symmetry, (Cambridge Monographs on Mechanics), Cambridge University Press, Cambridge, UK.
Oberleithner, K. , Sieber, M. , Nayeri, C. N. , Paschereit, C. O. , Petz, C. , Hege, H.-C. , Noack, B. R. , and Wygnanski, I. , 2011, “ Three-Dimensional Coherent Structures in a Swirling Jet Undergoing Vortex Breakdown: Stability Analysis and Empirical Mode Construction,” J. Fluid Mech., 679, pp. 383–414. [CrossRef]
Sieber, M. , Paschereit, C. O. , and Oberleithner, K. , 2016, “ Advanced Identification of Coherent Structures in Swirl-Stabilized Combustors,” ASME J. Eng. Gas Turbines Power, 139(2), p. 021503. [CrossRef]
Gallaire, F. , Ruith, M. , Meiburg, E. , Chomaz, J.-M. , and Huerre, P. , 2006, “ Spiral Vortex Breakdown as a Global Mode,” J. Fluid Mech., 549, pp. 71–80. [CrossRef]
Juniper, M. P. , 2012, “ Absolute and Convective Instability in Gas Turbine Fuel Injectors,” ASME Paper No. GT2012-68253.
Tammisola, O. , and Juniper, M. P. , 2016, “ Coherent Structures in a Swirl Injector at Re = 4800 by Nonlinear Simulations and Linear Global Modes,” J. Fluid Mech., 792(3), pp. 620–657. [CrossRef]
Rukes, L. , Sieber, M. , Paschereit Oliver, C. , and Oberleithner, K. , 2015, “ Transient Evolution of the Global Mode in Turbulent Swirling Jets: Experiments and Modal Stability Analysis,” Eur. J. Mech. B-Fluids, 65, pp. 98–106. https://doi.org/10.1016/j.euromechflu.2017.02.010
Mantič-Lugo, V. , Arratia, C. , and Gallaire, F. , 2015, “ A Self-Consistent Model for the Saturation Dynamics of the Vortex Shedding Around the Mean Flow in the Unstable Cylinder Wake,” Phys. Fluids, 27(7), p. 074103. [CrossRef]
Khorrami, M. R. , Malik, M. R. , and Ash, R. L. , 1989, “ Application of Spectral Collocation Techniques to the Stability of Swirling Flows,” J. Comput. Phys., 81(1), pp. 206–229. [CrossRef]
Huerre, P. , and Monkewitz, P. A. , 1990, “ Local and Global Instabilities in Spatially Developing Flows,” Annu. Rev. Fluid Mech., 22, pp. 473–537. [CrossRef]
Chomaz, J. M. , Huerre, P. , and Redekopp, L. G. , 1988, “ Bifurcations to Local and Global Modes in Spatially Developing Flows,” Phys. Rev. Lett., 60(1), pp. 25–28. [CrossRef] [PubMed]
Chomaz, J.-M. , Huerre, P. , and Redekopp, L. G. , 1991, “ A Frequency Selection Criterion in Spatially Developing Flows,” Stud. Appl. Math., 84(2), pp. 119–144. [CrossRef]
Rukes, L. , Paschereit Oliver, C. , and Oberleithner, K. , 2016, “ An Assessment of Turbulence Models for Linear Hydrodynamic Stability Analysis of Strongly Swirling Jets,” Eur. J. Mech. B/Fluids, 59, pp. 205–218. [CrossRef]
Stöhr, M. , Sadanandan, R. , and Meier, W. , 2011, “ Phase-Resolved Characterization of Vortex Flame Interaction in a Turbulent Swirl Flame,” Exp. Fluids, 51(4), pp. 1153–1167. [CrossRef]
Terhaar, S. , Ćosić, B. , Paschereit, C. , and Oberleithner, K. , 2016, “ Suppression and Excitation of the Precessing Vortex Core by Acoustic Velocity Fluctuations: An Experimental and Analytical Study,” Combust. Flame, 172, pp. 234–251. [CrossRef]
Yin, Z. , Nau, P. , and Meier, W. , 2016, “ Responses of Combustor Surface Temperature to Flame Shape Transitions in a Turbulent bi-Stable Swirl Flame,” Exp. Therm. Fluid Sci., 82, pp. 50–57. [CrossRef]
Terhaar, S. , Oberleithner, K. , and Paschereit, C. , 2015, “ Key Parameters Governing the Precessing Vortex Core in Reacting Flows: An Experimental and Analytical Study,” Proc. Combust. Inst., 35(3), pp. 3347–3354. [CrossRef]
Noack, B. R. , Afanasiev, K. , Morzyński, M. , Tadmor, G. , and Thiele, F. , 2003, “ A Hierarchy of Low-Dimensional Models for the Transient and Post-Transient Cylinder Wake,” J. Fluid Mech., 497, pp. 335–363. [CrossRef]
Barkley, D. , 2006, “ Linear Analysis of the Cylinder Wake Mean Flow,” Europhys. Lett, 75(5), pp. 750–756. [CrossRef]
Moeck, J. P. , Bourgouin, J.-F. , Durox, D. , Schuller, T. , and Candel, S. , 2012, “ Nonlinear Interaction Between a Precessing Vortex Core and Acoustic Oscillations in a Turbulent Swirling Flame,” Combust. Flame, 159(8), pp. 2650–2668. [CrossRef]

Figures

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Fig. 1

Schematics of gas turbine model combustor

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Fig. 2

Temporally smoothed and radially symmetrized flow and density field at the inlet versus time

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Fig. 3

(a) OH chemiluminescence images and simultaneous PIV and OH-PLIF measurements during phases of V- and M-shape and (b) temporal dynamics of the OH signal at the inlet

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Fig. 4

SPOD spectrum of the recorded transient. The dots represent the average frequency and energy of coupled SPOD modes, and the size and color (not available in printed version) of the dots represents the spectral coherence. The mode energy is displayed with respect to the total turbulent kinetic energy (TKE) of the flow. The most prominent modes are labeled and the corresponding mode shapes are shown in the images above, where streamlines represent the in-plane flow and colors indicate the transversal velocity component of the mode.

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Fig. 5

Dynamics of the V-M and M-V flame shape transition: The upper plot shows the SPOD coefficients of the PVC mode, the TA mode, and the shift mode. The lower plot shows the normalized OH signal at the inlet and the PVC growth rate σ obtained from the LSA.

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Fig. 6

Temporal variation of OH-PLIF signal near the chamber inlet (top) and bluff body temperature (bottom) during bistable flame shape transitions, reprinted from Ref. [30]

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Fig. 7

(a) Variation of axial velocity field during the V-flame period t = 0–568 ms before the onset of transition and (b) corresponding variation of the PVC growth rate σ

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Fig. 8

Sequence of PIV and OH-PLIF measurements showing the formation of the PVC and the subsequent detachment of the flame

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Fig. 9

Sequence of PIV and OH-PLIF measurements showing the transient attachment and detachment of the flame during one cycle of the TA instability

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