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

Advanced Identification of Coherent Structures in Swirl-Stabilized Combustors

[+] Author and Article Information
Moritz Sieber

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

Christian Oliver Paschereit, Kilian Oberleithner

Chair of Fluid Dynamics
Hermann-Föttinger-Institut,
Technische Universität Berlin,
Müller-Breslau-Street 8,
Berlin 10623, Germany

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 June 20, 2016; final manuscript received June 21, 2016; published online September 13, 2016. Editor: David Wisler.

J. Eng. Gas Turbines Power 139(2), 021503 (Sep 13, 2016) (8 pages) Paper No: GTP-16-1246; doi: 10.1115/1.4034261 History: Received June 20, 2016; Revised June 21, 2016

We present an application of a newly introduced method to analyze the time-resolved experimental data from the flow field of a swirl-stabilized combustor. This method is based on the classic proper orthogonal decomposition (POD) extended by a temporal constraint. The filter operation embedded in this method allows for continuous fading from the classic POD to the Fourier mode decomposition. This new method—called spectral proper orthogonal decomposition (SPOD)—allows for a clearer separation of the dominant mechanisms due to a clean spectral separation of phenomena. In this paper, the fundamentals of SPOD are shortly introduced. The actual focus is put on the application to a combustor flow. We analyze high-speed particle image velocimetry (PIV) measurements from flow fields in a combustor at different operation conditions. In these measurements, we consider externally actuated, as well as natural dynamics and reveal how the natural and actuated modes interact with each other. As shown in the paper, SPOD provides detailed insight into coherent structures in the swirl flames. Two distinct PVC structures are found that are very differently affected by acoustic actuation. The coherent structures are related to the heat release fluctuations, which are derived from simultaneously acquired OH* chemiluminescence measurements. Besides the actuated modes, a low frequency mode was found that significantly contribute to the global heat release fluctuations.

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References

Holmes, P. , Lumley, J. , and Berkooz, G. , 1998, “ Turbulence, Coherent Structures, Dynamical Systems and Symmetry,” Cambridge Monographs on Mechanics, Cambridge University Press, Cambridge, UK.
Poinsot, T. J. , Trouve, A. C. , Veynante, D. P. , Candel, S. M. , and Esposito, E. J. , 1987, “ Vortex-Driven Acoustically Coupled Combustion Instabilities,” J. Fluid Mech., 177(4), pp. 265–292. [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]
Rowley, C. W. , Mezic, I. , Bagheri, S. , Schlatter, P. , and Henningson, D. S. , 2009, “ Spectral Analysis of Nonlinear Flows,” J. Fluid Mech., 641, pp. 115–127. [CrossRef]
Schmid, P. J. , 2010, “ Dynamic Mode Decomposition of Numerical and Experimental Data,” J. Fluid Mech., 656, pp. 5–28. [CrossRef]
Sieber, M. , Paschereit, C. O. , and Oberleithner, K. , 2015, “ Spectral Proper Orthogonal Decomposition,” J. Fluid Mech., 792(4), pp. 798–828.
Paschereit, C. O. , Schuermans, B. , Polifke, W. , and Mattson, O. , 2002, “ Measurement of Transfer Matrices and Source Terms of Premixed Flames,” ASME J. Eng. Gas Turbines Power, 124(2), pp. 239–247. [CrossRef]
Willert, C. , and Gharib, M. , 1991, “ Digital Particle Image Velocimetry,” Exp. Fluids, 10(4), pp. 181–193. [CrossRef]
Soria, J. , 1996, “ An Investigation of the Near Wake of a Circular Cylinder Using a Video-Based Digital Cross-Correlation Particle Image Velocimetry Technique,” Exp. Therm. Fluid Sci., 12(2), pp. 221–233. [CrossRef]
Huang, H. T. , Fiedler, H. E. , and Wang, J. J. , 1993, “ Limitation and Improvement of PIV: Part II: Particle Image Distortion, a Novel Technique,” Exp. Fluids, 15(4–5), pp. 263–273.
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]
Rukes, L. , Sieber, M. , Paschereit, C. O. , and Oberleithner, K. , 2015, “ Effect of Initial Vortex Core Size on the Coherent Structures in the Swirling Jet Near Field,” Exp. Fluids, 56(10), p. 197. [CrossRef]
Rowley, C. W. , Colonius, T. , and Murray, R. M. , 2004, “ Model Reduction for Compressible Flows Using POD and Galerkin Projection,” Phys. D: Nonlinear Phenom., 189(12), pp. 115–129. [CrossRef]
Boree, J. , 2003, “ Extended Proper Orthogonal Decomposition: A Tool to Analyse Correlated Events in Turbulent Flows,” Exp. Fluids, 35(2), pp. 188–192. [CrossRef]
Terhaar, S. , Reichel, T. G. , Schrödinger, C. , Rukes, L. , Paschereit, C. O. , and Oberleithner, K. , 2014, “ Vortex Breakdown Types and Global Modes in Swirling Combustor Flows With Axial Injection,” J. Propul. Power, 31(1), pp. 219–229. [CrossRef]
Reichel, T. G. , Terhaar, S. , and Paschereit, O. , 2015, “ Increasing Flashback Resistance in Lean Premixed Swirl-Stabilized Hydrogen Combustion by Axial Air Injection,” ASME J. Eng. Gas Turbines Power, 137(7), p. 071503. [CrossRef]
Noack, B. R. , Afanasiev, K. , Morzynski, 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(12), pp. 335–363. [CrossRef]
Oberleithner, K. , Schimek, S. , and Paschereit, C. O. , 2015, “ Shear Flow Instabilities in Swirl-Stabilized Combustors and Their Impact on the Amplitude Dependent Flame Response: A Linear Stability Analysis,” Combust. Flame, 162(1), pp. 86–99. [CrossRef]

Figures

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Fig. 1

Sketch of the atmospheric combustion test-rig and measurement instrumentation

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Fig. 2

Natural mean velocity field (magnitude and streamlines)

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Fig. 3

Natural mean OH*-chemiluminescence field (de-Abeled) with superimposed streamlines

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Fig. 4

Relation between the sign of the crosswise velocities and the mode symmetries

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Fig. 5

POD (Nf = 0) modes of the natural flow

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Fig. 6

SPOD (Nf = 24) modes of the natural flow

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Fig. 7

SPOD spectrum (left) and spatial modes with mode coefficient spectrum (right) for increasing forcing amplitudes (from top to bottom the forcing amplitudes are 0, 10, 40, and 70% of the bulk velocity)

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Fig. 8

SPOD velocity modes Φi and the corresponding SPOD OH* modes Ωi for the dominant coherent structures

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Fig. 9

Time curve of the SPOD coefficient (ai) and the global heat release fluctuations (q′/q¯)

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Fig. 10

SPOD velocity modes Φi and corresponding SPOD OH* modes Ωi for the shift mode

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