Abstract

Targeting the severe mainstream ingestion and non-uniform coolant leakage problems of the endwall slashface, a novel inclined slashface structure is proposed based on a typical perpendicular slashface. The flow characteristics within different slashfaces and turbine cascades as well as the interaction between endwall gap leakages are numerically analyzed. The endwall cooling and blade phantom cooling performance with different slashface designs are compared. The results show that the mainstream ingests at a high axial velocity near the slashface leading edge and ejects out before the normalized axial location z/Cax of 0.6, forming a curved ingestion region. The inclined slashface, especially for α = 60 deg, directly prevents the mainstream ingestion at low blowing ratio, and it nearly eliminates the ingestion at high blowing ratio. The inclined slashface is also able to diminish the ingestion region on the downstream part at high blowing ratio. The slashface leakage influences the phantom cooling effect near the blade trailing edge by modifying the separation vortex. When M = 0.5, the length of endwall coolant coverage between 0.35 < z/Cax < 0.65 shrinks at α = 75 deg, and the cooling effectiveness at z/Cax > 0.8 is increased by 8.1%. When M = 1.0, two inclined designs separately increase the cooling effectiveness of upstream and downstream endwalls by 5.5–16.7% by placing the coolant in the crossflow region of the separation vortex. When M = 1.5, the slashface leakage ameliorates the cooling performance degradation at α = 90 deg. The phantom cooling effectiveness with α = 90 deg is decreased by 11.5% compared with inclined slashface. In summary, the slashface inclination angles of 60 deg and 75 deg have obvious endwall cooling and phantom cooling advantages over 90 deg under high blowing ratios, while they only gain a less advantage on the downstream part endwall under low blowing ratio. This research can provide guidelines for the design of multiple gaps on the turbine endwall.

References

1.
Giampaolo
,
T.
,
2020
,
Gas Turbine Handbook: Principles and Practice
,
CRC Press
,
Morgantown, WV
.
2.
Jeong
,
J. Y.
,
Jo
,
Y. R.
,
Kang
,
M. S.
,
Kang
,
Y. J.
, and
Kwak
,
J. S.
,
2024
, “
Film Cooling Effectiveness and Flow Structures of Butterfly-Shaped Film Cooling Hole Configuration
,”
ASME J. Therm. Sci. Eng. Appl.
,
16
(
3
), p.
031009
.
3.
Bunker
,
R. S.
,
2017
, “Evolution of Turbine Cooling,” ASME Paper No. GT2017-63205.
4.
Holgate
,
N. E.
,
Ireland
,
P. T.
, and
Romero
,
E.
,
2019
, “
The Effects of Combustor Cooling Features on Nozzle Guide Vane Film Cooling Experiments
,”
ASME J. Turbomach.
,
141
(
1
), p.
011005
.
5.
Wu
,
H.
,
Yang
,
X.
,
Zhao
,
Q.
, and
Feng
,
Z
,
2024
, “
Improving Turbine Endwall Overall Cooling Effectiveness Using Curtain Cooling and Redistributed Film-Hole Layouts: An Experimental and Computational Study
,”
ASME J. Therm. Sci. Eng. Appl.
,
16
(
3
), p.
031010
.
6.
Knisely
,
B. F.
,
Berdanier
,
R. A.
,
Wagner
,
J. H.
,
Thole
,
K. A.
,
Arisi
,
A. N.
and
Haldeman
,
C. W.
,
2023
, “
Effects of Part-to-Part Flow Variations on Overall Effectiveness and Life of Rotating Turbine Blades
,”
ASME J. Turbomach.
,
145
(
6
), p.
061016
.
7.
Langston
,
L. S.
,
Nice
,
M. L.
, and
Hooper
,
R. M.
,
1977
, “
Three-Dimensional Flow Within a Turbine Cascade Passage
,”
ASME J. Eng. Gas Turbines Power
,
99
(
1
), pp.
21
28
.
8.
El-Gabry
,
L.
,
Xu
,
H.
,
Liu
,
K.
,
Chang
,
J.
, and
Fox
,
M.
,
2018
, “Effect of Coolant Injection Angle on Nozzle Endwall Film Cooling: Experimental and Numerical Analysis in Linear Cascade,” ASME Paper No. GT2018-75877.
9.
Xu
,
S.
,
Pu
,
J.
,
Wang
,
J.
,
Chen
,
Y.
, and
Wu
,
W.
,
2022
, “
Effects of Mainstream Cross-Flow and Wall Contouring on Film Cooling Effectiveness of Cylindrical-Holes Embedded in Elliptical Craters
,”
Int. J. Heat Mass Transfer
,
194
(
1
), p.
123014
.
10.
Chen
,
P.
,
Wang
,
L.
,
Li
,
X.
,
Ren
,
J.
, and
Jiang
,
H.
,
2020
, “
Effect of Axial Turbine Non-Axisymmetric Endwall Contouring on Film Cooling at Different Locations
,”
Int. J. Heat Mass Transfer
,
147
(
1
), p.
118995
.
11.
Alqefl
,
M. H.
,
2019
,
Aero-Thermal Aspects of Endwall Cooling Flows in a Gas Turbine Nozzle Guide Vane
,
University of Minnesota
,
Minneapolis, MN
.
12.
Zhou
,
W.
,
Qenawy
,
M.
,
Shao
,
H.
,
Peng
,
D.
,
Wen
,
X.
, and
Liu
,
Y.
,
2020
, “
Turbine Vane Endwall Film Cooling With Barchan-Dune Shaped Ramp in a Single-Passage Transonic Wind Tunnel
,”
Int. J. Heat Mass Transfer
,
162
(
1
), p.
120350
.
13.
Shiau
,
C. C.
,
Sahin
,
I.
,
Wang
,
N.
,
Han
,
J. C.
,
Xu
,
H.
, and
Fox
,
M.
,
2019
, “
Turbine Vane Endwall Film Cooling Comparison From Five Film-Hole Design Patterns and Three Upstream Injection Angles
,”
ASME J. Therm. Sci. Eng. Appl.
,
11
(
3
), p.
031012
.
14.
Burdett
,
T. A.
,
Ullah
,
I.
,
Wright
,
L. M.
,
Han
,
J. C.
,
McClintic
,
J. W.
,
Crites
,
D. C.
and
Riahi
,
A.
,
2023
, “
Optimized Film Cooling Flow on a Contoured Endwall Within a Transonic Annular Cascade
,”
ASME J. Therm. Sci. Eng. Appl.
,
15
(
4
), p.
041011
.
15.
Liu
,
J.
,
Du
,
W.
,
Zhang
,
G.
,
Hussain
,
S.
,
Wang
,
L.
,
Xie
,
G.
, and
Sundén
,
B.
,
2020
, “
Design of Full-Scale Endwall Film Cooling of a Turbine Vane
,”
ASME J. Heat Transfer-Trans. ASME
,
142
(
2
), p.
022201
.
16.
Hada
,
S.
, and
Thole
,
K. A.
,
2006
, “Computational Study of a Midpassage Gap and Upstream Slot on Vane Endwall Film-Cooling,” ASME Paper No. GT2006-91067.
17.
Gao
,
F.
,
Chew
,
J. W.
, and
Marxen
,
O.
,
2020
, “
Inertial Waves in Turbine Rim Seal Flows
,”
Phys. Rev. Fluids
,
5
(
2
), p.
024802
.
18.
Horwood
,
J. T. M.
,
Hualca
,
F. P.
,
Scobie
,
J. A.
,
Wilson
,
M.
,
Sangan
,
C. M.
, and
Lock
,
G. D.
,
2019
, “
Experimental and Computational Investigation of Flow Instabilities in Turbine Rim Seals
,”
ASME J. Eng. Gas Turbines Power
,
141
(
1
), p.
011028
.
19.
Müller
,
G.
,
Landfester
,
C.
,
Böhle
,
M.
, and
Krewinkel
,
R.
,
2020
, “
Turbine Vane Endwall Film Cooling Effectiveness of Different Purge Slot Configurations in a Linear Cascade
,”
ASME J. Turbomach.
,
142
(
3
), p.
031008
.
20.
Shote
,
A. S.
,
Mahmood
,
G. I.
, and
Meyer
,
J. P.
,
2020
, “
Influences of Large Fillets on Endwall Flows in a Vane Cascade With Upstream Slot Film-Cooling
,”
Exp. Therm. Fluid Sci.
,
112
(
1
), p.
109951
.
21.
Du
,
Q.
,
Xu
,
G.
,
Xu
,
Q.
, and
Wang
,
P.
,
2022
, “
Detached Eddy Simulation of the Unsteady Flow and Film Cooling Characteristics of an Endwall With an Interrupted Slot
,”
ASME J. Turbomach.
,
144
(
10
), p.
101012
.
22.
Park
,
S.
,
Kim
,
J. J.
,
Bang
,
M.
,
Moon
,
H. K.
,
Ueda
,
O.
, and
Cho
,
H. H.
,
2021
, “
Effects of Seal Installation in the Mid-Passage Gap Between Turbine Blade Platforms on Film Cooling
,”
Appl. Therm. Eng.
,
189
(
1
), p.
116683
.
23.
Roy
,
A.
,
Jain
,
S.
,
Ekkad
,
S. V.
,
Ng
,
W.
,
Lohaus
,
A. S.
,
Crawford
,
M. E.
, and
Abraham
,
S.
,
2014
, “Heat Transfer Performance of a Transonic Turbine Blade Passage in Presence of Leakage Flow Through Upstream Slot and Mateface Gap With Endwall Contouring,” ASME Paper No. GT2014-26476.
24.
Piggush
,
J. D.
, and
Simon
,
T. W.
,
2007
, “
Measurements of Net Change in Heat Flux as a Result of Leakage and Steps on the Contoured Endwall of a Gas Turbine First Stage Nozzle
,”
Appl. Therm. Eng.
,
27
(
4
), pp.
722
730
.
25.
Chowdhury
,
N. H. K.
,
Shiau
,
C. C.
,
Han
,
J. C.
,
Zhang
,
L.
, and
Moon
,
H. K.
,
2017
, “
Turbine Vane Endwall Film Cooling With Slashface Leakage and Discrete Hole Configuration
,”
ASME J. Turbomach.
,
139
(
6
), p.
061003
.
26.
Park
,
S.
,
Sohn
,
H. S.
,
Shin
,
S.
,
Ueda
,
O.
,
Moon
,
H. K.
, and
Cho
,
H. H.
,
2021
, “
Film Cooling Characteristics on Blade Platform With a Leakage Flow Through Mid-Passage Gap
,”
Int. J. Heat Mass Transfer
,
167
(
1
), p.
120800
.
27.
Mao
,
S.
,
Van
,
H. D.
,
Zhang
,
K.
,
Lee
,
J. W.
,
Ng
,
W. F.
,
Xu
,
H.
,
Fox
,
M.
, and
Li
,
J.
,
2023
, “
Upstream Jet Cooling and Dual Cavity Slashface Leakage Cooling on a Transonic Nozzle Guide Vane Endwall
,”
ASME J. Turbomach.
,
145
(
8
), p.
081006
.
28.
Han
,
J. C.
,
2018
, “
Advanced Cooling in Gas Turbines 2016 Max Jakob Memorial Award Paper
,”
ASME J. Heat Transfer-Trans. ASME
,
140
(
11
), p.
113001
.
29.
Anthony
,
R. J.
,
Finnegan
,
J.
, and
Clark
,
J.
,
2025
, “
Phantom Cooling Effects on Rotor Blade Surface Heat Flux in a Transonic Full Scale 1 + 1/2 Stage Rotating Turbine
,”
ASME J. Turbomach.
,
147
(
3
), p.
031016
.
30.
Zhang
,
Y.
, and
Yuan
,
X.
,
2012
, “Experimental Investigation of Turbine Phantom Cooling on Suction Side With Combustor-Turbine Leakage Gap Flow and Endwall Film Cooling,” ASME Paper No. GT2012-69295.
31.
Zhang
,
L.
,
Yin
,
J.
,
Liu
,
K.
, and
M.
Hee-Koo
,
2015
, “Effect of Hole Diameter on Nozzle Endwall Film Cooling and Associated Phantom Cooling,” ASME Paper No. GT2015-42541.
32.
Du
,
K.
,
Li
,
Z.
,
Li
,
J.
, and
Sunden
,
B.
,
2017
, “
Influence of the Upstream Slot Geometry on the Endwall Cooling and Phantom Cooling of Vane Suction Side Surface
,”
Appl. Therm. Eng.
,
121
(
1
), pp.
688
700
.
33.
Zhang
,
K.
,
Li
,
Z.
, and
Li
,
J.
,
2021
, “
Influence of Slashface Leakage Coupled With Quasi-Labyrinth Seal Technique on Gas Turbine Endwall Aerothermal Performance and Blade Suction Side Surface Phantom Cooling
,”
IMech Part A: J. Power Energy
,
235
(
3
), pp.
351
367
.
34.
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
.
35.
Zhang
,
K.
,
Li
,
Z.
, and
Li
,
J.
,
2021
, “
Turbine Endwall Cooling and Heat Transfer Characteristics Under Slashface Leakage Interacted With Nearby Discrete-Hole Injections
,”
Int. J. Therm. Sci.
,
170
(
1
), p.
107167
.
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