The goal of this study was to determine how showerhead blowing on a turbine vane leading edge affects of the performance of film cooling jets farther downstream. An emphasis was placed on measurements above the surface, i.e., flow visualization, thermal field, and velocity field measurements. The film cooling performance on the pressure side of a simulated turbine vane, with and without showerhead blowing, was examined. Results presented in this paper are for low mainstream turbulence; high mainstream turbulence effects are presented in the companion paper. At the location of the pressure side row of holes, the showerhead coolant extended a distance of about $3d$ from the surface $(d$ is the coolant hole diameter). The pressure side was found to be subjected to high turbulence levels caused by the showerhead injection. Results indicate a greater dispersion of the pressure side coolant jets with showerhead flow due to the elevated turbulence levels.

1.
Ericksen
,
V. L.
, and
Goldstein
,
R. J.
,
1974
, “
Heat Transfer and Film Cooling Following Injection Through Inclined Circular Tubes
,”
ASME J. Heat Transfer
,
96
, pp.
239
245
.
2.
Muska
,
J. F.
,
Fish
,
R. W.
, and
Suo
,
M.
,
1976
, “
The Additive Nature of Film Cooling from Rows of Holes
,”
ASME J. Eng. Power
,
98
, pp.
457
474
.
3.
Drost, U., and Bo¨lcs, A., 1999, “Performance of a Turbine Airfoil with Multiple Film Cooling Stations Part I: Heat Transfer and Film Cooling Effectiveness,” ASME Paper No. 99-GT-171.
4.
Ethridge
,
M. I.
,
Cutbirth
,
J. M.
, and
Bogard
,
D. G.
,
2001
, “
Scaling of Performance for Varying Density Ratio Coolants on an Airfoil with Strong Curvature and Pressure Gradient Effects
,”
ASME J. Turbomach.
,
123
, pp.
1
7
.
5.
Polanka, M. D., Ethridge, M. I., Cutbirth, J. M., and Bogard, D. G., 2000, “Effects of Showerhead Injection on Film Cooling Effectiveness of Downstream Rows of Holes,” ASME Paper No. 2000-GT-240.
6.
Cutbirth, J. M., and Bogard, D. G., 2001, “Thermal Field and Flow Visualization Within the Stagnation Region of a Film Cooled Turbine Vane,” ASME Paper No. 2001-GT-401.
7.
Cutbirth
,
J. M.
, and
Bogard
,
D. G.
,
2002
, “
Evaluation of Pressure Side Film Cooling With Flow and Thermal Field Measurements—Part II: Turbulence Effects
,”
ASME J. Turbomach.
,
124
, pp.
678
685
.
8.
Polanka, M. D., 1999, “Detailed Film Cooling Effectiveness and Three Component Velocity Field Measurements on a First Stage Turbine Vane Subject to High Freestream Turbulence,” Ph.D. Dissertation, The University of Texas at Austin.
9.
Cutbirth, J. M., 2000, “Turbulence and Three-Dimensional Effects on the Film Cooling of a Turbine Vane,” Ph.D. dissertation, The University of Texas at Austin.
10.
Witteveld, V. C., Polanka, M. D., and Bogard, D. G., 1999, “Film Cooling Effectiveness in the Showerhead Region of a Gas Turbine Vane Part I: Stagnation Region and Near-Suction Side,” ASME Paper No. 99-GT-49.
11.
Sellers
,
J. P.
,
1963
, “
Gaseous Film Cooling with Multiple Injection Stations
,”
AIAA J.
,
1
, No.
9
, pp.
2154
2156
.
12.
Polanka, M. D., Witteveld, V. C., and Bogard, D. G., 1999, “Film Cooling Effectiveness in the Showerhead Region of a Gas Turbine Vane Part I: Stagnation Region and Near-Pressure Side,” ASME Paper No. 99-GT-48.
13.
Radomsky, R. W., and Thole, K. A., 1998, “Effects of High Freestream Turbulence Levels and Length Scales on Stator Vane Heat Transfer,” ASME Paper No. 98-GT-236.
14.
Polanka, M. D., Cutbirth, J. M., and Bogard, D. G., 2001, “Three Component Velocity Field Measurements in the Stagnation Region of a Film Cooled Vane,” ASME Paper No. 2000-GT-240.