In the present study, two measurement techniques are adopted to evaluate the fuel–air mixing under atmospheric conditions using an industrial fuel–air premixer. These techniques are CO2 mixing and planar laser induced fluorescence (PLIF) in water. In these techniques, CO2 and fluorescent dye are injected as fuel simulants. CO2 measurements are used to validate PLIF in water. In the CO2 technique, CO2 concentrations are converted to fuel mass fractions, whereas in the PLIF technique, a modified post processing method is used to convert the LIF signal into fuel mass fraction. The experiments are conducted at the same Reynolds number and momentum flux ratio for two injection strategies. To study the effect of the flow aerodynamics on the mixing results, high-speed particle image velocimetry (PIV) measurements are conducted in water at the same Reynolds number. A comparison of fuel concentrations measured with the CO2 and PLIF techniques shows good quantitative agreement at all momentum flux ratios. However, deviations between the two techniques are observed at locations of high fuel concentration gradients. The unsteady mixing is evaluated using the PLIF technique with high temporal resolution. Analysis of PIV and PLIF data shows that unsteady mixing is lower at regions of high fluctuations in velocity. Moreover, it is found that there is high unsteady mixing at locations of high concentration gradient.

References

References
1.
Correa
,
S.
,
1991
, “
A Review of NOx Formation Under Gas-Turbine Combustion Conditions
,”
Combust. Sci. Technol.
,
87
(
1–6
), pp.
329
362
.
2.
Lefebvre
,
A. H.
,
1995
, “
The Role of Fuel Preparation in Low-Emission Combustion
,”
ASME J. Eng. Gas Turbines Power
,
117
(
4
), pp.
617
654
.
3.
Davis
,
L. B.
,
1996
, “
Dry Low Nox Combustion Systems for GE Heavy-Duty Gas Turbines
,”
ASME
Paper No. 96-GT-027.
4.
Zeldovich
,
J.
,
1946
, “
The Oxidation of Nitrogen in Combustion and Explosions
,”
Acta Physicochim.
,
21
(
4
), pp.
577
628
.
5.
Lefebvre
,
A. H.
,
1999
,
Gas Turbine Combustion
,
Taylor and Francis Group
,
New York
.
6.
Davis
,
D.
,
Nolan
,
J.
,
Brumberg
,
J.
,
Yilmaz
,
E.
,
Varatharajan
,
B.
, and
Goldmeer
,
J.
,
2007
, “
The Effect of Fuel Density on Mixing Profiles in a DACRS Pre-Mixer: Experiments and Simulation
,”
ASME
Paper No. GT2007-27878.
7.
Zajadatz
,
M.
,
Lachner
,
R.
,
Bernero
,
S.
,
Motz
,
C.
, and
Flohr
,
P.
,
2007
, “
Development and Design of ALSTOM'S Staged Fuel Gas Injection EV Burner for NOx Reduction
,”
ASME
Paper No. GT2007-27730.
8.
Lacarelle
,
A.
,
Goke
,
S.
, and
Paschereit
,
C. O.
,
2010
, “
A Quantitative Link Between Cold-Flow Scalar Unmixedness and NOx Emissions in a Conical Premixed Burner
,”
ASME
Paper No. GT2010-23132.
9.
Lacarelle
,
A.
,
Matho
,
L.
, and
Paschereit
,
C. O.
,
2010
, “
Scalar Mixing Enhancement in a Swirl Stabilized Combustor Through Passive and Active Injection Control
,”
AIAA
Paper No. 2010-1332.
10.
Estefanos
,
W.
,
Tambe
,
S.
, and
Jeng
,
S. M.
,
2015
, “
A Study of the Mean and Dynamic Behavior of the Swirling Flow Generated by a Counter Rotating Radial-Radial Swirler Using a Water Test Rig
,”
ASME
Paper No. GT2015-43464.
11.
Walker
,
D.
,
1987
, “
A Fluorescence Technique for Measurement of Concentration in Mixing Liquids
,”
J. Phys. E
,
20
(
2
), pp. 217–224.
12.
Margason
,
R. J.
,
1993
, “
Fifty Years of Jet in Cross Flow Research
,”
AGARD Meeting on Computational and Experimental Assessment of Jets in Cross Flow
, Winchester, UK, Apr. 19–22, p. 1.
13.
Liscinsky
,
D. S.
,
True
,
B.
, and
Holdeman
,
J. D.
,
1993
, “
Experimental Investigation of Crossflow Jet Mixing in a Rectangular Duct
,”
AIAA
Paper No. 93-2037.
14.
Dimotakis
,
P. E.
, and
Miller
,
P. L.
,
1990
, “
Some Consequences of the Boundedness of Scalar Functions
,”
Phys. Fluids A
,
2
(
11
), pp. 1919–1920.
You do not currently have access to this content.