0
Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

Characterization of Different Actuator Designs for the Control of the Precessing Vortex Core in a Swirl-Stabilized Combustor

[+] Author and Article Information
Finn Lückoff

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

Moritz Sieber, Christian Oliver Paschereit, Kilian Oberleithner

Chair of Fluid Dynamics,
Hermann-Föttinger-Institut,
Technische Universität Berlin,
Müller-Breslau-Str. 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 July 11, 2017; final manuscript received July 31, 2017; published online October 31, 2017. Editor: David Wisler.

J. Eng. Gas Turbines Power 140(4), 041503 (Oct 31, 2017) (10 pages) Paper No: GTP-17-1340; doi: 10.1115/1.4038039 History: Received July 11, 2017; Revised July 31, 2017

The precessing vortex core (PVC) represents a helical-shaped coherent flow structure typically occurring in both reacting and nonreacting swirling flows. Until now, the fundamental impact of the PVC on flame dynamics, thermoacoustic instabilities, and pollutant emissions is still unclear. In order to identify and investigate these mechanisms, the PVC needs to be controlled effectively with a feedback control system. A previous study successfully applied feedback control in a generic swirling jet setup. The next step is to transfer this approach into a swirl-stabilized combustor, which poses big challenges on the actuator and sensor design and placement. In this paper, different actuator designs are investigated with the goal of controlling the PVC dynamics. The actuation strategy aims to force the flow near the origin of the instability—the so-called wavemaker. To monitor the PVC dynamics, arrays of pressure sensors are flush-mounted at the combustor inlet and the combustion chamber walls. The best sensor placement is evaluated with respect to the prediction of the PVC dynamics. Particle image velocimetry (PIV) is used to evaluate the passive impact of the actuator shape on the mean flow field. The performance of each actuator design is evaluated from lock-in experiments showing excellent control authority for two out of seven actuators. All measurements are conducted at isothermal conditions in a prototype of a swirl-stabilized combustor.

FIGURES IN THIS ARTICLE
<>
Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Syred, N. , 2006, “ A Review of Oscillation Mechanisms and the Role of the Precessing Vortex Core (PVC) in Swirl Combustion Systems,” Prog. Energy Combust. Sci., 32(2), pp. 93–161. [CrossRef]
Petz, C. , Hege, H.-C. , Oberleithner, K. , Sieber, M. , Nayeri, C. N. , Paschereit, C. O. , Wygnanski, I. , and Noack, B. R. , 2011, “ Global Modes in a Swirling Jet Undergoing Vortex Breakdown,” Phys. Fluids, 23(9), p. 091102. [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]
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]
Qadri, U. A. , Mistry, D. , and Juniper, M. P. , 2013, “ Structural Sensitivity of Spiral Vortex Breakdown,” J. Fluid Mech., 720, pp. 558–581. [CrossRef]
Tammisola, O. , and Juniper, M. , 2016, “ Coherent Structures in a Swirl Injector at Re = 4800 by Nonlinear Simulations and Linear Global Modes,” J. Fluid Mech., 792, pp. 620–657. [CrossRef]
Rukes, L. , Paschereit, C. O. , and Oberleithner, K. , 2016, “ An Assessment of Turbulence Models for Linear Hydrodynamic Stability Analysis of Strongly Swirling Jets,” Eur. J. Mech.: B, 59, pp. 205–218. [CrossRef]
Oberleithner, K. , Stöhr, M. , Im, S. H. , Arndt, C. M. , 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]
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]
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]
Ghani, A. , Poinsot, T. , Gicquel, L. , and Müller, J.-D. , 2016, “ LES Study of Transverse Acoustic Instabilities in a Swirled Kerosene/Air Combustion Chamber,” Flow, Turbul. Combust., 96(1), pp. 207–226. [CrossRef]
Stöhr, M. , Arndt, C. , and Meier, W. , 2015, “ Transient Effects of Fuel–Air Mixing in a Partially-Premixed Turbulent Swirl Flame,” Proc. Combust. Inst., 35(3), pp. 3327–3335. [CrossRef]
Terhaar, S. , Krüger, O. , and Paschereit, C. O. , 2015, “ Flow Field and Flame Dynamics of Swirling Methane and Hydrogen Flames at Dry and Steam-Diluted Conditions,” ASME J. Eng. Gas Turbines Power, 137(4), p. 041503. [CrossRef]
Kuhn, P. , Moeck, J. P. , Paschereit, C. O. , and Oberleithner, K. , 2016, “ Control of the Precessing Vortex Core by Open and Closed-Loop Forcing in the Jet Core,” ASME Paper No. GT2016-57686.
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]
Oberleithner, K. , Terhaar, S. , Rukes, L. , and Paschereit, C. O. , 2013, “ Why Nonuniform Density Suppresses the Precessing Vortex Core,” ASME J. Eng. Gas Turbines Power, 135(12), p. 121506. [CrossRef]
Li, L. K. B. , and Juniper, M. P. , 2013, “ Lock-In and Quasiperiodicity in a Forced Hydrodynamically Self-Excited Jet,” J. Fluid Mech., 726, pp. 624–655. [CrossRef]
Sieber, M. , Paschereit, C. O. , and Oberleithner, K. , 2016, “ Spectral Proper Orthogonal Decomposition,” J. Fluid Mech., 792, pp. 798–828. [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]
Akilli, H. , Sahin, B. , and Rockwell, D. , 2003, “ Control of Vortex Breakdown by a Coaxial Wire,” Phys. Fluids, 15(1), pp. 123–133. [CrossRef]
Leuckel, W. , 1967, “ Swirl Intensities, Swirl Types and Energy Losses of Different Swirl Generating Devices,” International Flame Research Foundation, Ijmuiden, The Netherlands, Technical Report No. G02/a/16. http://copac.jisc.ac.uk/id/27957912?style=html&title=Swirl%20intensities%2C%20swirl%20types%20and%20energy%20losses%20of
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,” Exp. Fluids, 15(4–5), pp. 263–273. [CrossRef]
Holmes, P. , Lumley, J. L. , and Berkooz, G. , 1998, Turbulence, Coherent Structures, Dynamical Systems and Symmetry (Cambridge Monographs on Mechanics), Cambridge University Press, Cambridge, UK.
Terhaar, S. , Reichel, T. G. , Schrödinger, C. , Rukes, L. , Paschereit, C. O. , and Oberleithner, K. , 2015, “ Vortex Breakdown Types and Global Modes in Swirling Combustor Flows With Axial Injection,” J. Propul. Power, 31(1), pp. 219–229.
Greenblatt, D. , and Wygnanski, I. J. , 2000, “ The Control of Flow Separation by Periodic Excitation,” Prog. Aerosp. Sci., 36(7), pp. 487–545. [CrossRef]
Li, L. K. , and Juniper, M. , 2013, “ Phase Trapping and Slipping in a Forced Hydrodynamically Self-Excited Jet,” J. Fluid Mech., 735, p. R5.

Figures

Grahic Jump Location
Fig. 1

Three-dimensional visualization of a velocity field including a PVC from Ref. [2]. Reconstructed from particle image velocimetry (PIV) snapshots at Reynolds number Re = 20,000. Central streak-lines surrounding a helical streak-surface depict the PVC. Spiral vortices induced by helical waves can be seen in the outer shear layer. The internal recirculation zone in the center is shown as a pathline-surface surrounded by the PVC streak surface.

Grahic Jump Location
Fig. 2

Test rig with PIV setup. Section ①: actuation unit with four loudspeakers and actuation channels; section ②: burner with swirl generator, mixing tube containing centerbody inside; section ③: quartz glass combustion chamber.

Grahic Jump Location
Fig. 3

Different arrangements of pressure sensors in the front plate (left) and the mixing tube (right)

Grahic Jump Location
Fig. 4

Complete view, detailed tip, and equivalent pictograph of all seven centerbody designs arranged one below the other. Arrows indicate the directions of actuating jets. Each design generates four individual jets.

Grahic Jump Location
Fig. 5

Contours of the mean axial velocity component of shaped (left) and cylindrical (right) centerbody, Re = 16,000. Streamlines are derived from the mean axial and transverse velocity component. The bold lines indicate zero axial velocity.

Grahic Jump Location
Fig. 6

SPOD results for shaped centerbody (lower row) and cylindrical centerbody (upper row). Each decomposition is represented by an SPOD spectrum (left) where a dot indicates a mode pair that is placed according to its energy and frequency. The size and shading of the dot indicate the spectral coherence of a mode pair. On the right side, the spatial structure Φ (upper row) and the power density spectrum of the coefficient a (lower row) are given for selected modes. The spatial mode is indicated by crosswise velocity plus streamlines of the mean flow.

Grahic Jump Location
Fig. 7

Amplitudes Ap of the pressure coefficients p1̂ scaled with the maximum amplitude (left) and phase error variance between ai and p̂1 (right) for all considered sensor positions

Grahic Jump Location
Fig. 8

Cμ (Re = 16,000) for actuator VII (left) and maximum Cμ for different actuator concepts (right). The Cμ estimated for the actuator IV is also valid for actuator III, indicated by the label “III/IV” on the left, since the only difference is the outer geometry which does not influence these measurements without flow.

Grahic Jump Location
Fig. 10

Spectra of spatial Fourier modes (m = {0, 1, 2}) for different actuation amplitudes (compare Fig. 9): ff = 125 Hz, fn = 115 Hz, Δf = 8.7%, and Re = 19,000

Grahic Jump Location
Fig. 9

Spectra of spatial Fourier modes (m = {0, 1, 2}) for different actuation amplitudes using the actuator design indicated by the small pictograph in the top-left corner. The spectra are deduced from the pressure sensors located at the combustor front plate. Forcing frequency ff = 112 Hz, which is at Δf = 18.5% relative to the natural PVC frequency of fn = 94.5 Hz at Re = 16,000.

Grahic Jump Location
Fig. 11

Amplitude of the natural PVC mode (m = 1; shaped tip: fn = 94.5 Hz, flat tip: fn = 88 Hz) taken from power spectral density spectra over forcing amplitude (left), and amplitude of the actuated mode (m = 1; shaped tip: ff = 102 Hz, flat tip: ff = 95 Hz) depending on the forcing strength (right), Re = 16,000, Δf = 8%, compare Figs. 9 and 10

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In