For this study, a simulated film cooled turbine blade leading edge, constructed of a special high conductivity material, was used to determine the normalized “metal temperature” representative of actual engine conditions. The Biot number for the model was matched to that for operational engine conditions, ensuring that the normalized wall temperature, i.e., the overall effectiveness, was matched to that for the engine. Measurements of overall effectiveness were made for models with and without thermal barrier coating (TBC) at various operating conditions. This was the first study to experimentally simulate TBC and the effects on overall effectiveness. Two models were used: one with a single row of holes along the stagnation line, and the second with three rows of holes straddling the stagnation line. Film cooling was operated using a density ratio of 1.5 and for range of blowing ratios from $M=0.5$ to $M=3.0$. Both models were tested using a range of angles of attack from 0.0 deg to ±5.0 deg. As expected, the TBC coated models had significantly higher external surface temperatures, but lower metal temperatures. These experimental results provide a unique database for evaluating numerical simulations of the effects of TBC on leading edge film cooling performance.

1.
Soechting
,
F. O.
, 1999, “
A Design Perspective on Thermal Barrier Coatings
,”
J. Therm. Spray Technol.
1059-9630,
8
(
4
), pp.
505
511
.
2.
Bogard
,
D. G.
, and
Thole
,
K. A.
, 2006, “
Gas Turbine Film Cooling
,”
J. Propul. Power
0748-4658,
22
(
2
), pp.
249
270
.
3.
Harrison
,
K.
and
Bogard
,
D.
, 2008, “
Use of the Adiabatic Wall Temperature in Film Cooling to Predict Wall Heat Flux and Temperature
,” ASME Paper No. GT2008-51424.
4.
Albert
,
J. E.
,
Bogard
,
D. G.
, and
Cunha
,
F.
, 2004, “
,” ASME Paper No. GT2004-53998.
5.
Mouzon
,
B. D.
,
Terrell
,
E. J.
,
Albert
,
J. E.
, and
Bogard
,
D. G.
, 2005, “
Net Heat Flux Reduction and Overall Effectiveness for a Turbine Blade Leading Edge
,” ASME Paper No. GT2005-69002.
6.
Na
,
S.
,
Williams
,
B.
,
Dennis
,
R. A.
,
Bryden
,
K. M.
, and
Shih
,
T. I.-P.
, 2007, “
Internal and Film Cooling of a Flat Plate With Conjugate Heat Transfer
,”
Proceedings of the 2007 ASME Turbo Expo
.
7.
Johnson
,
R. G.
, 2008, “
Experimental Study of the Effect of Oscillating Stagnation Line on Overall Cooling Performance on a Leading Edge With One Row of Cooling Holes
,” MS thesis, University of Texas at Austin, Austin, TX.
8.
Maikell
,
J. S.
, 2008, “
Experimental Study of the Effect of TBC and Angle of Attack on Overall Cooling Performance on a Leading Edge With One and Three Rows of Cooling Holes
,” MS thesis, University of Texas at Austin, Austin, TX.
9.
Clarke
,
D. R.
, and
Phillpot
,
S. R.
, 2005, “
Thermal Barrier Coating Materials
,”
Mater. Today
1369-7021,
8
(
6
), pp.
22
29
.