This study investigates the influence of the fuel injection strategy on safety against flashback in a gas turbine model combustor with premixing of H2–air mixtures. The flashback propensity is quantified and the flashback mechanism is identified experimentally. The A2EV swirler concept exhibits a hollow, thick-walled conical structure with four tangential slots. Four fuel injector geometries were tested. One of them injects the fuel orthogonal to the air flow in the slots (jet-in-crossflow injector (JICI)). Three injector types introduce the fuel almost isokinetic to the air flow at the trailing edge of the swirler slots (trailing edge injector (TEI)). Velocity and mixing fields in mixing zone and combustion chamber in isothermal water flow were measured with high-speed particle image velocimetry (PIV) and high-speed laser-induced fluorescence (LIF). The flashback limit was determined under atmospheric pressure for three air mass flows and 673 K preheat temperature for H2–air mixtures. Flashback mechanism and trajectory of the flame tip during flashback were identified with two stereoscopically oriented intensified high-speed cameras observing the OH* radiation. We notice flashback in the core flow due to combustion-induced vortex breakdown (CIVB) and turbulent flame propagation (TFP) near the wall dependent on the injector type. The flashback resistance (FBR) defined as the ratio between a characteristic flow speed and a characteristic flame speed measures the direction of propagation of a turbulent flame in the flow field. Although CIVB cannot be predicted solely based on the FBR, its distribution gives evidence for CIVB-prone states. The fuel should be injected preferably isokinetic to the air flow along the entire trailing edge in order to reduce the RMS fluctuation of velocity and fuel concentration. The characteristic velocity in the entire cross section of the combustion chamber inlet should be at least twice the characteristic flame speed. The position of the stagnation point should be tuned to be located in the combustion chamber by adjusting the axial momentum. Those measures lead to safe operation with highly reactive fuels at high equivalence ratios.

References

References
1.
EERE Information Center
,
2010
, “
Fuel Cell Technologies Program
,” U.S. Department of Energy, Washington, DC, Technical Report No. 1-877-337-3463.
2.
Lieuwen
,
T.
,
McDonell
,
V.
,
Santavicca
,
D.
, and
Sattelmayer
,
T.
,
2008
, “
Burner Development and Operability Issues Associated With Steady Flowing Syngas Fired Combustors
,”
Combust. Sci. Technol.
,
180
(
6
), pp.
1169
1192
.
3.
Lewis
,
B.
, and
von Elbe
,
G.
,
1943
, “
Stability and Structure of Burner Flames
,”
J. Chem. Phys.
,
11
(
2
), pp.
75
97
.
4.
Putnam
,
A. A.
, and
Jensen
,
R. A.
,
1949
, “
Application of Dimensionless Numbers to Flash-Back and Other Combustion Phenomena
,”
Third Symposium on Combustion, Flame and Explosion Phenomena
, pp.
89
98
.
5.
Eichler
,
C.
,
Baumgartner
,
G.
, and
Sattelmayer
,
T.
,
2012
, “
Experimental Investigation of Turbulent Boundary Layer Flashback Limits for Premixed Hydrogen–Air Flames Confined in Ducts
,”
ASME J. Eng. Gas Turbines Power
,
134
(
1
), p.
011502
.
6.
Eichler
,
C.
, and
Sattelmayer
,
T.
,
2012
, “
Premixed Flame Flashback in Wall Boundary Layers Studied by Long-Distance Micro-PIV
,”
Exp. Fluids
,
52
(
2
), pp.
347
360
.
7.
Eichler
,
C.
,
2011
, “
Flame Flashback in Wall Boundary Layers of Premixed Combustion Systems
,”
Ph.D. thesis
, Technische Universität München, München, Germany.
8.
Baumgartner
,
G.
,
2014
, “
Flame Flashback in Premixed Hydrogen–Air Combustion Systems
,” Ph.D. thesis, Technische Universität München, München, Germany.
9.
Baumgartner
,
G.
,
Böck
,
L.
, and
Sattelmayer
,
T.
,
2015
, “
Experimental Investigation of the Transition Mechanism From Stable Flame to Flashback in a Generic Premixed Combustion System With High-Speed Micro-PIV and Micro-PLIF Combined With Chemiluminescence Imaging
,”
ASME
Paper No. GT2015-42605.
10.
Fritz
,
J.
,
2003
, “
Flammenrückschlag durch verbrennungsinduziertes Wirbelaufplatzen
,” Ph.D. thesis, Technische Universität München, München, Germany.
11.
Kröner
,
M.
,
2003
, “
Einfluss lokaler Löschvorgänge auf den Flammenrückschlag durch verbrennungsinduziertes Wirbelaufplatzen
,” Ph.D. thesis, Technische Universität München, München, Germany.
12.
Konle
,
M.
,
2010
, “
Verbrennungsinduziertes Wirbelaufplatzen in moderat turbulenten Drallströmungen
,” Ph.D. thesis, Technische Universität München, München, Germany.
13.
Konle
,
M.
, and
Sattelmayer
,
T.
,
2009
, “
Prediction of CIVB Driven Flame Flashback for CH4–H2–Air Mixtures and Moderate Turbulence
,”
22nd International Colloquium on the Dynamics of Explosions and Reactive Systems
, Luikov Heat and Mass Transfer Institute, Minsk, Belarus, July 27–31.
14.
Ashurst
,
W. T.
,
1996
, “
Flame Propagation Along a Vortex: The Baroclinic Push
,”
Combust. Sci. Technol.
,
112
(
1
), pp.
175
185
.
15.
Burmberger
,
S.
,
2008
, “
Optimierung der aerodynamischen Flammenstabilisierung für brennstoffflexible, vorgemischte Gasturbinenbrenner
,” Ph.D. thesis, Technische Universität München, München, Germany.
16.
Burmberger
,
S.
, and
Sattelmayer
,
T.
,
2011
, “
Optimization of the Aerodynamic Flame Stabilization for Fuel Flexible Gas Turbine Premix Burners
,”
ASME J. Eng. Gas Turbines Power
,
133
(
10
), p.
101501
.
17.
Sangl
,
J.
,
2011
, “
Erhöhung der Brennstoffflexibilität von Vormischbrennern durch Beeinflussung der Wirbeldynamik
,” Ph.D. thesis, Technische Universität München, München, Germany.
18.
Sangl
,
J.
,
Mayer
,
C.
, and
Sattelmayer
,
T.
,
2011
, “
Dynamic Adaptation of Aerodynamic Flame Stabilization of a Premix Swirl Burner to Fuel Reactivity Using Fuel Momentum
,”
ASME J. Eng. Gas Turbines Power
,
133
(
7
), p.
071501
.
19.
Mayer
,
C.
,
2012
, “
Konzept zur vorgemischten Verbrennung wasserstoffhaltiger Brennstoffe in Gasturbinen
,” Ph.D. thesis, Technische Universität München, München, Germany.
20.
Mayer
,
C.
,
Sangl
,
J.
,
Sattelmayer
,
T.
,
Lachaux
,
T.
, and
Bernero
,
S.
,
2012
, “
Study on the Operational Window of a Swirl Stabilized Syngas Burner Under Atmospheric and High Pressure Conditions
,”
ASME J. Eng. Gas Turbines Power
,
134
(
3
), p.
031506
.
21.
Sattelmayer
,
T.
,
Mayer
,
C.
, and
Sangl
,
J.
,
2014
, “
Interaction of Flame Flashback Mechanisms in Premixed Hydrogen–Air Swirl Flames
,”
ASME
Paper No. GT2014-25553.
22.
Marosky
,
A.
,
Seidel
,
V.
,
Bless
,
S.
, and
Sattelmayer
,
T.
,
2012
, “
Impact of Cooling Air Injection on the Primary Combustion Zone of a Swirl Burner
,”
ASME
Paper No. GT2012-68898.
23.
Fritz
,
Y.
,
Kröner
,
M.
, and
Sattelmayer
,
T.
,
2004
, “
Flashback in a Swirl Burner With Cylindrical Premixing Zone
,”
ASME J. Eng. Gas Turbines Power
,
126
(
2
), pp.
276
283
.
24.
Kröner
,
M.
,
Fritz
,
Y.
, and
Sattelmayer
,
T.
,
2003
, “
Flashback Limits for Combustion Induced Vortex Breakdown in a Swirl Burner
,”
ASME J. Eng. Gas Turbines Power
,
125
(
3
), pp.
693
700
.
25.
Peters
,
N.
,
2006
,
Turbulent Combustion
,
Cambridge University Press
,
Cambridge, UK
.
26.
Pope
,
S. B.
,
2005
,
Turbulent Flows
,
Cambridge University Press
,
Cambridge, UK
.
27.
Virginia Tech
,
2012
, “
Prana 2.0b
,” Virginia Polytechnic Institute and State University, Blacksburg, VA, accessed Mar. 16, 2016,
sourceforge.net/projects/qi-tools/
28.
LaVision
,
2011
, “
Product Manual for Davis 8.0: LIF in Liquid Fluids
,” LaVision GmbH, Göttingen, Germany.
29.
Marosky
,
A.
,
2014
, “
Einfluss der Kühllufteindüsung auf das Betriebsverhalten von Drallbrennern
,” Ph.D. thesis, Technische Universität München, München, Germany.
30.
Peters
,
N.
,
1994
, “
Turbulente Brenngeschwindigkeit
,” RWTH Aachen, Aachen, Germany, Technical Report No. Pe 241/9-2.
31.
Otsu
,
N.
,
1979
, “
A Threshold Selection Method From Gray-Level Histograms
,”
IEEE Trans. Syst. Man Cybern.
,
9
(
1
), pp.
62
66
.
32.
Dribinski
,
V.
,
Ossadtchi
,
A.
,
Mandelshtam
,
V. A.
, and
Reisler
,
H.
,
2002
, “
Reconstruction of Abel-Transformable Images: The Gaussian Basis-Set Expansion Abel Transform Method
,”
Rev. Sci. Instrum.
,
73
(
7
), pp.
2634
2642
.
33.
Chterev
,
I.
,
Sundararajan
,
G.
,
Seitzman
,
J. M.
, and
Lieuwen
,
T.
,
2015
, “
Precession Effects on the Relationship Between Time-Averaged and Instantaneous Swirl Flow and Flame Characteristics
,”
ASME
Paper No. GT2015-42768.
34.
Wang
,
Q.
,
McDonell
,
V.
,
Steinthorsson
,
E.
,
Mansour
,
A.
, and
Hollon
,
B.
,
2009
, “
Correlating Flashback Tendencies for Premixed Injection of Hydrogen and Methane Mixtures at Elevated Temperature and Pressure
,”
ASME
Paper No. GT2009-59500.
35.
Seidel
,
V.
,
2014
, “
Numerische und experimentelle Untersuchungen der Aerodynamik und Verbrennungsstabilität eines Vormischbrenners
,” Ph.D. thesis, Technische Universität München, München, Germany.
36.
Reichel
,
T. G.
,
Terhaar
,
S.
, and
Paschereit
,
C. O.
,
2014
, “
Increasing Flashback Resistance in Lean Premixed Swirl-Stabilized Hydrogen Combustion by Axial Air Injection
,”
ASME
Paper No. GT2014-27002.
You do not currently have access to this content.