Predictions of turbine blade film cooling have traditionally employed Reynolds-averaged Navier-Stokes solvers and two-equation models for turbulence. Evaluation of several versions of such models have revealed that the existing two-equation models fail to resolve the anisotropy and the dynamics of the highly complex flow field created by the jet-crossflow interaction. A more accurate prediction of the flow field can be obtained from large eddy simulations (LES) where the dynamics of the larger scales in the flow are directly resolved. In the present paper, such an approach has been used, and results are presented for a row of inclined cylindrical holes at blowing ratios of 0.5 and 1 and Reynolds numbers of 11,100 and 22,200, respectively, based on the jet velocity and hole diameter. Comparison of the time-averaged LES predictions with the flow measurements of Lavrich and Chiappetta (UTRC Report No. 90-04) shows that LES is able to predict the flow field with reasonable accuracy. The unsteady three-dimensional flow field is shown to be dominated by packets of hairpin-shaped vortices. The dynamics of the hairpin vortices in the wake region of the injected jet and their influence on the unsteady wall heat transfer are presented. Generation of “hot spots” and their migration on the film-cooled surface are associated with the entrainment induced by the hairpin structures. Several geometric properties of a “mixing interface” around hairpin coherent structures are presented to illustrate and quantify their impact on the entrainment rates and mixing processes in the wake region.

Issue Section:
Technical Papers
Keywords:
Navier-Stokes equations, flow simulation, turbulence, vortices, wakes, stratified flow, jets, cooling, heat transfer
Topics:
Coolants, Cooling, Dynamics (Mechanics), Film cooling, Flow (Dynamics), Heat transfer, Large eddy simulation, Vortices, Wakes, Turbulence, Scalars, Temperature
1.
Garg, V. K., and Gaugler R. E., 1994, “Prediction of Film Cooling on Gas Turbine Airfoils,” ASME paper no. 94-GT-2.
2.
Garg, V. K., and Gaugler R. E., 1995, “Effect of Velocity and Temperature Distribution at the Hole Exit on Film Cooling of Turbine Blades,” ASME paper no. 95-GT-2.
3.
Berhe, M. K., and Patankar, S., 1996, “A Numerical Study of Discrete-Hole Film Cooling,” ASME paper 96-WA/HT-8.
4.
Walters, D. K. and Leylek, J. H., 1997, “A Detailed Analysis of Film-Cooling Physics Part 1: Streamwise Injection with Cylindrical Holes,” ASME paper no. 97-GT-269.
5.
Lakehal
,
D.
,
Theodoridis
,
G. S.
, and
Rodi
,
W.
,
1998
, “
Computation of Film Cooling of a Flat Plate by Lateral Injection from a Row of Holes
,”
Int. J. Heat Fluid Flow
,
19
, pp.
418
–
430
.
6.
Acharya
,
S.
,
Tyagi
,
M.
, and
Hoda
,
A.
,
2001
, “
Flow and Heat Transfer Predictions for Film Cooling,” Heat transfer in gas turbine systems
,
Ann. N.Y. Acad. Sci.
,
934
, pp.
110
–
125
.
7.
Hoda, A., Acharya, S., and Tyagi, M., 2000, “Predictions of a Jet-In-Crossflow with Reynolds Stress Transport Models and Large Eddy Simulations,” ASME-IGTI00, Munich.
8.
Vreman
,
B.
,
Geurts
,
B. J.
, and
Kuerten
,
H.
,
1994
, “
On the Formulation of the Dynamic Mixed Subgrid Scale Model
,”
Phys. Fluids
,
6
, pp.
4057
–
4059
.
9.
Tyagi, M., and Acharya, S., 2001, “Flow and Heat Transfer Predictions for the Film-Cooling Flow Using Large Eddy Simulations,” DNS/LES Progress and Challenges, C. Liu, L. Sakell, and T. Beutner, eds., Gryden Press, Columbus, OH, pp. 799–806.
10.
Yusof, J. M., 1996, “Interaction of Massive Particles with Turbulence,” Ph.D. dissertation, Cornell University, Ithaca, NY.
11.
Fadlun
,
E.
,
Verzicco
,
R.
,
Orlandi
,
P.
, and
Yusof
,
J. M.
,
2000
, “
Combined Immersed Boundary Finite Difference Methods for Complex Flow Simulations
,”
J. Comput. Phys.
,
161
, pp.
35
–
60
.
12.
Moin
,
P.
,
Squires
,
K.
,
Cabot
,
W.
, and
Lee
,
S.
,
1991
, “
A Dynamic Subgrid-Scale Model for Compressible Turbulence and Scalar Transport
,”
Phys. Fluids A
,
11
, pp.
2746
–
2757
.
13.
Lavrich, P. L., and Chiappetta, L. M., 1990, “An Investigation of Jet in a Cross Flow for Turbine Film Cooling Applications,” United Technologies Research Center, UTRC Report No. 90-04.
14.
Sinha
,
A. K.
,
Bogard
,
D. G.
, and
Crawford
,
M. E.
,
1991
, “
Film-Cooling Effectiveness Downstream of a Single Row of Holes with Variable Density Ratio
,”
ASME J. Turbomach.
,
113
, pp.
442
–
449
.
15.
Fric
,
T. F.
, and
Roshko
,
A.
,
1994
, “
Vortical Structure in the Wake of a Transverse Jet
,”
J. Fluid Mech.
,
279
, pp.
1
–
47
.
16.
Kelso
,
R. M.
,
Lim
,
T. T.
, and
Perry
,
A. E.
,
1996
, “
An Experimental Study of Round Jets in Crossflow
,”
J. Fluid Mech.
,
306
, pp.
111
–
144
.
17.
Muldoon, F., and Acharya, S., 1999, “Numerical Investigation of the Dynamical Behavior of a Row of Square Jets in Crossflow Over a Surface,” ASME-IGTI99.
18.
Eiff
,
O. S.
, and
Keffer
,
J. F.
,
1997
, “
On the Structures in the Near-Wake Region of an Elevated Turbulent Jet in a Crossflow
,”
J. Fluid Mech.
,
333
, pp.
161
–
195
.
19.
Blanchard
,
J. N.
,
Brunet
,
Y.
, and
Merlen
,
A.
,
1999
, “
Influence of a Counter Rotating Vortex Pair on the Stability of a Jet in a Crossflow: An Experimental Study by Flow Visualizations
,”
Exp. Fluids
,
26
, pp.
63
–
74
.
20.
Wray, A. A., and Hunt, J. C. R., 1989, “Algorithms for Classification of Turbulent Structures,” Topological Fluid Mechanics, H. K. Moffat and A. Tsinober, eds., Cambridge University Press, Cambridge, UK, pp. 95–104.
21.
Tanaka
,
M.
, and
Kida
,
S.
,
1993
, “
Characterization of Vortex Tubes and Sheets
,”
Phys. Fluids A
,
5
, pp.
2079
–
2082
.
22.
Dubief
,
Y.
, and
Delcayre
,
F.
,
2000
, “
On Coherent-Vortex Identification in Turbulence
,”
J. Turbulence
,
1
, pp.
1
–
22
.
23.
Smith
,
C. R.
,
Walker
,
J. D. A.
,
Haidari
,
A. H.
, and
Soburn
,
U.
,
1991
, “
On the Dynamics of Near-Wall Turbulence
,”
Philos. Trans. R. Soc. London
,
336
, pp.
131
–
175
.
24.
Rivero
,
A.
,
Ferre
,
J. A.
, and
Giralt
,
F.
,
2001
, “
Organized Motions in a Jet in Crossflow
,”
J. Fluid Mech.
,
444
, pp.
117
–
149
.
25.
Camussi
,
R.
,
Guj
,
G.
, and
Stella
,
A.
,
2002
, “
Experimental Study of a Jet in Crossflow at Very Low Reynolds Number
,”
J. Fluid Mech.
,
454
, pp.
113
–
144
.
26.
Southerland, K. B., Frederikson, R. D., Dahm, W. J. A., and Dowling, D. R., 1995, “Comparisons of Mixing in Chaotic and Turbulent Flows,” Chaos Applied to Fluid Mixing, Pergamon, Oxford, UK, pp. 313–345.
27.
Geurts, B. J., 2002, “Buoyant Turbulent Mixing in Shear Layers,” Advances Turbulence IX, Proceedings of the 9th European Turbulence Conference, I. P. Castro, P. E. Hancock, and T. G. Thomas, eds., CIMNE, Barcelona.
28.
Haven
,
B. A.
, and
Kurosaka
,
M.
,
1997
, “
Kidney and Anti-Kidney Vortices in Crossflow Jets
,”
J. Fluid Mech.
,
352
, pp.
27
–
64
.
Copyright © 2003
 by ASME
You do not currently have access to this content.