An experimental and numerical study was performed about the influence of incoming wakes and the calming effect on a very high-lift low-pressure turbine rotor blade. The first part of the paper describes the experimental determination of the pressure loss coefficient and the heat transfer around the blade mounted in a high-speed linear cascade. The cascade is exposed to incoming wakes generated by high-speed rotating bars. Their aim is to act upon the transition/separation phenomena. The measurements were conducted at a constant exit Mach number equal to 0.8 and at three Reynolds number values; namely, 190,000, 350,000, and 650,000. The inlet turbulence level was fixed at 0.8%. An additional feature of this work is to identify the boundary layer status through heat transfer measurements. Compared to the traditionally used hot films, thin film heat flux gages provide fully quantitative data required for code validation. Numerical computations are presented in the second part of the paper.

1.
Zweifel
,
O.
,
1945
, “
The Spacing of Turbo-Machine Blading, Especially with Large Angular Deflection
,”
Brown Boveri Rev.
,
32
(
12
), pp.
436
444
.
2.
Emmons
,
H. W.
,
1951
, “
The Laminar-Turbulent Transition in a Boundary Layer—Part I
,”
J. Aerosp. Sci.
,
18
, pp.
490
498
.
3.
Schubauer, G. B., and Klebanoff, P. S., 1955, “Contributions on the Mechanics of Boundary Layer Transition,” NACA TN 3489; and 1289, 1956 NACA Rep.
4.
Curtis
,
E. M.
,
Hodson
,
H. P.
,
Banieghbal
,
M. R.
,
Denton
,
J. D.
,
Howell
,
R. J.
, and
Harvey
,
N. W.
,
1997
, “
Development of Blade Profiles for Low-Pressure Turbine Applications
,”
ASME J. Turbomach.
,
119
, pp.
531
538
.
5.
Howell
,
R. J.
,
Ramesh
,
O. N.
,
Hodson
,
H. P.
,
Harvey
,
N. W.
, and
Schulte
,
V.
,
2001
, “
High Lift and Aft-Loaded Profiles for Low-Pressure Turbines
,”
ASME J. Turbomach.
,
123
, pp.
181
188
.
6.
Brunner, S., Fottner, L., and Schiffer, H.-P., 2000, “Comparison of Two Highly Loaded Low Pressure Turbine Cascades under the Influence of Wake-Induced Transition,” ASME Paper 2000-GT-268.
7.
Solomon, W. J., 2000, “Effects of Turbulence and Solidity on the Boundary Layer Development in a Low Pressure Turbine,” ASME Paper 2000-GT-273.
8.
Mayle, R. E., 1991, “Fundamental Aspects of Boundary Layers and Transition in Turbomachines,” VKI Lecture Series on “Boundary Layers in Turbomachines,” LS 1991-06.
9.
Gostelow
,
J. P.
,
Melwani
,
N.
, and
Walker
,
G. J.
,
1996
, “
Effects of Streamwise Pressure Gradient on Turbulent Spot Development
,”
ASME J. Turbomach.
,
118
, pp.
737
743
.
10.
Gostelow
,
J. P.
,
Walker
,
G. J.
,
Solomon
,
W. J.
,
Hong
,
G.
, and
Melwani
,
N.
,
1997
, “
Investigation of the Calmed Region Behind a Turbulent Spot
,”
ASME J. Turbomach.
,
119
, pp.
802
809
.
11.
Halstead
,
D. E.
,
Wisler
,
D. C.
,
Okiishi
,
T. H.
,
Walker
,
G. J.
,
Hodson
,
H. P.
, and
Shin
,
H.
,
1997
, “
Boundary Layer Development in Axial Compressors and Turbines: Part 1—Composite Picture; Part 2—Compressors; Part 3—LP Turbines; Part 4—Computations and Analyses
,”
ASME J. Turbomach.
,
119
, pp.
114
127
, 426–444, 225–237, 128–139.
12.
Schulte
,
V.
, and
Hodson
,
H. P.
,
1998
, “
Prediction of the Becalmed Region for LP Turbine Profile Design
,”
ASME J. Turbomach.
,
120
, pp.
839
846
.
13.
Schultz, M. P., and Volino, R. J., 2001, “Effects of Concave Curvature on Boundary Layer Transition under High Free-Stream Turbulence Conditions,” ASME Paper 2001-GT-0191.
14.
LaGraff
,
J. E.
,
Ashworth
,
D. A.
, and
Schultz
,
D. L.
,
1989
, “
Measurement and Modeling of the Gas Turbine Blade Transition Process as Disturbed by Wakes
,”
ASME J. Turbomach.
,
111
, pp.
315
322
.
15.
Ashworth
,
D. A.
,
LaGraff
,
J. E.
, and
Schultz
,
D. L.
,
1989
, “
Unsteady Interaction Effects on a Transitinal Turbine Blade Boundary Layer
,”
ASME J. Turbomach.
,
111
, pp.
162
168
.
16.
Arts
,
T.
, and
Lambert de Rouvroit
,
M.
, January
1992
, “
Aero-Thermal Performance of a 2-D Highly Loaded Transonic Turbine Nozzle Guide Vane: A Test Case for Inviscid and Viscous Flow computations
,”
ASME J. Turbomach.
,
114
, pp.
147
154
.
17.
Roux, J.-M., Lefebvre, M., and Liamis, N., 2002, “Unsteady and Calming Effects Investigation on a Very High Lift LP Turbine Blade—Part II: Numerical Analysis,” ASME Paper GT-2002-30228.
18.
Schultz, D. L., and Jones, T. V., 1973, “Heat Transfer Measurements in Short-Duration Facility,” AGARDograph No. 165.
19.
Bons
,
J. P.
,
Sondergaard
,
R.
, and
Rivir
,
R. B.
,
2001
, “
Turbine Separation Control Using Pulsed Vortex Generator Jets
,”
ASME J. Turbomach.
,
123
, pp.
198
206
.
20.
Coton, T., Arts, T., and Lefebvre, M., 2001, “Effects of Reynolds and Mach Number on the Profile Losses of a Conventional Low Pressure Turbine Rotor Cascade with Increasing Pitch to Chord Ratio,” 4th European Conference on Turbomachinery, ATI-CST-011/01, pp. 139–150.
21.
Brear, M. J., Hodson, H. P., Gonzalez, P., and Harvey, N. W., 2001, “Pressure Surface Separations in Low Pressure Turbines: Part 2—Interactions With the Secondary Flow,” ASME Paper 2001-GT-0438.
22.
D’Ovidio, A., Harkins, J. A., and Gostelow, J. P., 2001, “Turbulent Spots in Strong Adverse Pressure Gradients. Part 2—Spot Propagation and Spreading Rates,” ASME Paper 2001-GT-0406.
23.
Wu
,
X.
,
Jacobs
,
R. G.
,
Hunt
,
J. C. R.
, and
Durbin
,
P. A.
,
1999
, “
Simulation of Boundary Layer Transition Induced by Periodically Passing Wakes
,”
J. Fluid Mech.
,
398
, pp.
109
153
.
24.
Zhong
,
S.
,
Kittichaikan
,
C.
,
Hodson
,
H. P.
, and
Ireland
,
P. T.
,
2000
, “
Visualization of Turbulent Spots under the Influence of Adverse Pressure Gradients
,”
Exp. Fluids
,
28
(
5
), pp.
385
293
.
25.
Schobeiri, M. T., Chakka, P., and Pappu, K., 1998, “Unsteady Wake Effects on Boundary Layer Transition and Heat Transfer Characteristics of a Turbine Blade,” ASME Paper 98-GT-291.
26.
Hedley
,
T. B.
, and
Keffer
,
J. F.
,
1974
, “
Turbulent/Non-Turbulent Decisions in an Intermittent Flow
,”
J. Fluid Mech.
,
64
, pp.
625
644
.
27.
Funazaki, k., Kitazawa, T., Koizumi, K., and Tanuma, T., 1997, “Studies on Wake-Disturbed Boundary Layer under the Influences of Favorable Pressure Gradient and Free-Stream Turbulence—Part I—Experimental Setup and Discussion on Transition Model,” ASME 1997-GT-451.
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