Abstract

In the vicinity of gas turbine blades, a complex flow field is formed due to the flow separation, reattachment, and secondary flows, and this results in a locally non-uniform and high heat transfer on the surfaces. The present study experimentally investigates the effects of leakage flow through the slot between the gas turbine vane and blade rows on the film cooling effectiveness of the forward region of the shroud ring segment. The experiment is carried out in a linear cascade with five blades. Instead of the vane, a row of rods at the location of the vane trailing edge is installed to consider the wake effect. The leakage flow is introduced through the slot between the vane and blade rows, and additional coolant air is injected from the cooling holes installed at the vane’s outer zone. The effects of the slot geometry, cooling hole configuration, and blowing ratio on the film cooling effectiveness are experimentally investigated using the pressure-sensitive paint (PSP) technique. CO2 gas and a mixture of SF6 and N2 (25% + 75%) are used to simulate the leakage flow to the mainstream density ratios of 1.5 and 2.0, respectively. The results indicate that the area-averaged film cooling effectiveness is affected more by the slot width than by the cooling hole configuration at the same injection conditions, and the lower density ratio cases show higher film cooling effectiveness than the higher density ratio case at the same cooling configuration.

References

1.
Kacker
,
S. C.
, and
Whitelaw
,
J. H.
,
1968
, “
The Effect of Slot Height and Slot Turbulence Intensity on the Effectiveness of the Uniform Density, Two-Dimensional Wall Jet
,”
ASME J. Heat Trans.
,
90
(
4
), pp.
469
475
. 10.1115/1.3597544
2.
Kacker
,
S. C.
, and
Whitelaw
,
J. H.
,
1969
, “
An Experimental Investigation of the Influence of Slot-Lip-Thickness on the Impervious-Wall Effectiveness of the Uniform-Density, Two-Dimensional Wall Jet
,”
Int. J. Heat Mass Transfer
,
12
(
9
), pp.
1196
1201
. 10.1016/0017-9310(69)90129-X
3.
Sivasegaram
,
S.
, and
Whitelaw
,
J. H.
,
1969
, “
Film Cooling Slots: The Importance of Lip Thickness and Injection Angle
,”
J. Mech. Eng. Sci.
,
11
(
1
), pp.
22
27
. 10.1243/JMES_JOUR_1969_011_005_02
4.
Goldstein
,
R. J.
,
1971
, “
Film Cooling
,”
Adv. Heat Transfer
,
7
, pp.
321
379
. 10.1016/S0065-2717(08)70020-0
5.
Jia
,
R.
,
Sundén
,
B.
,
Miron
,
P.
, and
Léger
,
B.
,
2005
, “
A Numerical and Experimental Investigation of the Slot Film-Cooling Jet With Various Angles
,”
ASME J. Turbomach.
,
127
(
3
), pp.
635
645
. 10.1115/1.1929821
6.
Thole
,
K. A.
, and
Knost
,
D. G.
,
2005
, “
Heat Transfer and Film-Cooling for the Endwall of a First Stage Turbine Vane
,”
Int. J. Heat Mass Transfer
,
48
(
25–26
), pp.
5255
5269
. 10.1016/j.ijheatmasstransfer.2005.07.036
7.
Papa
,
M.
,
Srinivasan
,
V.
, and
Goldstein
,
R. J.
,
2012
, “
Film Cooling Effect of Rotor-Stator Purge Flow in Endwall Heat/Mass Transfer
,”
ASME J. Turbomach.
,
134
(
4
), p.
041014
. 10.1115/1.4003725
8.
Wright
,
L. M.
,
Gao
,
Z.
,
Yang
,
H.
, and
Han
,
J. C.
,
2008
, “
Film Cooling Effectiveness Distribution on a Gas Turbine Blade Platform With Inclined Slot Leakage and Discrete Film Hole Flows
,”
ASME J. Heat Trans.
,
130
(
7
), p.
071702
. 10.1115/1.2907440
9.
Gao
,
Z.
,
Narzary
,
D.
, and
Han
,
J. C.
,
2009
, “
Turbine Blade Platform Film Cooling With Typical Stator-Rotor Purge Flow and Discrete-Hole Film Cooling
,”
ASME J. Turbomach.
,
131
(
4
), p.
041004
. 10.1115/1.3068327
10.
Oke
,
R. A.
, and
Simon
,
T. W.
,
2002
, “
Film Cooling Experiments With Flow Introduced Upstream of a First Stage Nozzle Guide Vane Through Slots of Various Geometries
,”
Proceedings of the ASME Turbo Expo 2002: Power for Land, Sea, and Air
,
Amsterdam, The Netherlands
,
June 3–6, 2002
, pp.
33
40
, ASME Paper No. GT-2002-30169.
11.
Müller
,
G.
,
Böhle
,
M.
,
Landfester
,
C.
, and
Krewinkel
,
R.
,
2019
, “
Turbine Vane Endwall Film Cooling Effectiveness of Different Purge Slot Configurations in a Linear Cascade
,”
Proceedings of the ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition
,
Phoenix, AZ
,
June 17–21, 2019
, ASME Paper No. GT2019-90236, V05BT19A004.
12.
Yao
,
Y.
,
Zhu
,
P.
,
Tao
,
Z.
,
Song
,
L.
, and
Li
,
J.
,
2019
, “
Experimental Study on the Effects of Slot Jet on Film Cooling Performance in the Cascade Endwall With Purge Flow
,”
Proceedings of the ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition
,
Phoenix, AZ
,
June 17–21, 2019
, ASME Paper No. GT2019-90667, V05BT19A010.
13.
Tao
,
Z.
,
Yao
,
Y.
,
Zhe
,
P.
,
Song
,
L.
, and
Li
,
J.
,
2020
, “
Experimental and Numerical Study on Film Cooling Effectiveness of an Annular Cascade Endwall With Different Slot Configuration
,”
Int. J. Therm. Sci.
,
158
, p.
106517
. 10.1016/j.ijthermalsci.2020.106517
14.
Roy
,
A.
,
Blot
,
D. M.
,
Ekkad
,
S. V.
,
Ng
,
W. F.
,
Lohaus
,
A. S.
, and
Crawford
,
M. E.
,
2013
, “
Effect of Upstream Purge Slot on a Transonic Turbine Blade Passage: Part 2-Heat Transfer Performance
,”
Proceedings of the ASME Turbo Expo 2013: Turbine Technical Conference and Exposition
,
San Antonio, TX
,
June 3–7, 2013
, ASME Paper No. GT2013-94581, V03BT13A021.
15.
Roy
,
A.
,
Jain
,
S.
,
Ekkad
,
S. V.
,
Ng
,
W.
,
Lohaus
,
A. S.
,
Crawford
,
M. E.
, and
Abraham
,
S.
,
2017
, “
Heat Transfer Performance of a Transonic Turbine Blade Passage in the Presence of Leakage Flow Through Upstream Slot and Mateface Gap With Endwall Contouring
,”
ASME J. Turbomach.
,
139
(
12
), p.
121006
. 10.1115/1.4037909
16.
Chen
,
A. F.
,
Shiau
,
C. C.
, and
Han
,
J. C.
,
2017
, “
Turbine Blade Platform Film Cooling With Simulated Swirl Purge Flow and Slashface Leakage Conditions
,”
ASME J. Turbomach.
,
139
(
3
), p.
031012
. 10.1115/1.4034985
17.
Du
,
K.
,
Li
,
J.
,
Li
,
J.
, and
Sunden
,
B.
,
2018
, “
Effects of the Swirling Coolant jet From the Upstream Slot on the Vane Endwall Cooling and the Vane Suction Side Phantom Cooling
,”
Int. J. Heat Mass Transfer
,
121
, pp.
952
966
. 10.1016/j.ijheatmasstransfer.2018.01.068
18.
Wright
,
L. M.
,
Blake
,
S. A.
,
Rhee
,
D. H.
, and
Han
,
J. C.
,
2009
, “
Effect of Upstream Wake With Vortex on Turbine Blade Platform Film Cooling With Simulated Stator-Rotor Purge Flow
,”
ASME J. Turbomach.
,
131
(
2
), p.
021017
. 10.1115/1.2952365
19.
Gao
,
Z.
,
Narzry
,
D. P.
,
Mhetras
,
S.
, and
Han
,
J. C.
,
2012
, “
Upstream Vortex Effect on Turbine Platform Film Cooling With Typical Purge Flow
,”
J. Thermophys. Heat Trans.
,
26
(
1
), pp.
75
84
. 10.2514/1.42411
20.
Choi
,
S. M.
,
Kim
,
J.
,
Bang
,
M.
,
Kim
,
J.
, and
Cho
,
H. H.
,
2018
, “
Effect of the Wake on the Heat Transfer of a Turbine Blade Endwall According to Relative Position of the Cylindrical Rod
,”
Int. Commun. Heat Mass
,
94
, pp.
61
70
. 10.1016/j.icheatmasstransfer.2018.03.011
21.
Tamunobere
,
O.
,
Drewes
,
C.
,
Acharya
,
S.
, and
Nakamata
,
C.
,
2015
, “
Heat Transfer to an Actively Cooled Shroud With Blade Rotation
,”
ASME J. Therm. Sci. Eng. Appl.
,
7
(
4
), p.
041020
. 10.1115/1.4031357
22.
Collins
,
M.
,
Chana
,
K.
, and
Povey
,
T.
,
2017
, “
Application of Film Cooling to an Unshrouded High-Pressure Turbine Casing
,”
ASME J. Turbomach.
,
139
(
6
), p.
061010
. 10.1115/1.4035276
23.
Han
,
J. C.
, and
Rallabandi
,
A. P.
,
2010
, “
Turbine Blade Film Cooling Using PSP Technique
,”
Front. Heat Mass Transfer
,
1
(
1
), p.
013001
. 10.5098/hmt.v1.1.3001
24.
Charbonnier
,
D.
,
Ott
,
P.
,
Jonsson
,
M.
,
Cottier
,
F.
, and
Köbke
,
T.
,
2009
, “
Experimental and Numerical Study of the Thermal Performance of a Film Cooled Turbine Platform
,”
Proceedings of the ASME Turbo Expo 2009: Power for Land, Sea, and Air
,
Orlando, FL
,
June 8–12, 2009
, pp.
1027
1038
, ASME Paper No. GT2009-60306.
25.
Strozik
,
M.
,
Majkut
,
M.
, and
Dykas
,
S.
,
2015
, “
Measuring System for Pressure Sensitive Paint (PSP) Calibration in the Range of Low Pressure Gains
,”
Mod. Appl. Sci.
,
9
(
2
), pp.
116
122
. 10.5539/mas.v9n2p116
26.
L’Ecuyer
,
M. R.
, and
Soechting
,
F. O.
,
1985
, “
A Model for Correlating Flat Plate Film Cooling Effectiveness for Rows of Round Holes
,”
The Propulsion and Energetic Panel 65th Symposium
,
Bergen, Norway
,
May 6–10
,
AGRAD Conference Proceedings, No. 390
.
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