The leading edge of a turbine vane is subject to some of the highest temperature loading within an engine, and an accurate understanding of leading edge film coolant behavior is essential for modern engine design. Although there have been many investigations of the adiabatic effectiveness for showerhead film cooling of a vane leading edge region, there have been no previous studies in which individual rows of the showerhead were tested with the explicit intent of validating superposition models. For the current investigation, a series of adiabatic effectiveness experiments were performed with a five-row and three-row showerhead. The experiments were repeated separately with each individual row of holes active. This allowed evaluation of superposition methods on both the suction side of the vane, which was moderately convex, and the pressure side of the vane, which was mildly concave. Superposition was found to accurately predict performance on the suction side of the vane at lower momentum flux ratios, but not at higher momentum flux ratios. On the pressure side of the vane, the superposition predictions were consistently lower than measured values, with significant errors occurring at the higher momentum flux ratios. Reasons for the underprediction by superposition analysis are presented.

References

References
1.
Sellers
,
J. P.
,
1963
, “
Gaseous Film Cooling With Multiple Injection Stations
,”
AIAA J.
,
1
(
9
), pp.
2154
2156
.10.2514/3.2014
2.
Witteveld
,
V. C.
,
Polanka
,
M. D.
, and
Bogard
,
D. G.
,
1999
, “
Film Cooling Effectiveness in the Showerhead Region of a Gas Turbine Vane—Part II: Stagnation Region and Near Suction Side
,”
ASME
Paper No. 99-GT-049.
3.
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-048.
4.
Cutbirth
,
J. M.
, and
Bogard
,
D. G.
,
2002
, “
Thermal Field and Flow Visualization Within the Stagnation Region of a Film Cooled Turbine Vane
,”
ASME J. Turbomach.
,
124
(
2
), pp.
200
206
.10.1115/1.1451086
5.
Nathan
,
M. L.
,
Dyson
,
T. E.
,
Bogard
,
D. G.
, and
Bradshaw
,
S. D.
,
2013
, “
Adiabatic and Overall Effectiveness for the Showerhead Film Cooling of a Turbine Vane
,”
ASME J. Turbomach.
,
136
(
3
), p.
031005
.10.1115/1.4024680
6.
Albert
,
J. E.
, and
Bogard
,
D. G.
,
2013
, “
Measurements of Adiabatic Film and Overall Cooling Effectiveness on a Turbine Vane Pressure Side With a Trench
,”
ASME J. Turbomach.
,
135
(
5
), p.
051007
.10.1115/1.4007820
7.
Hylton
,
L. D.
,
Milhec
,
M. S.
,
Turner
,
E. R.
,
Nealy
,
D. A.
, and
York
,
R. E.
,
1983
, “
Analytical and Experimental Evaluation of the Heat Transfer Distribution Over the Surface of Turbine Vanes
,” NASA Lewis Research Center, Cleveland, OH, Contractor Report No. 168015.
8.
Dees
,
J. E.
,
Ledezma
,
G. A.
,
Bogard
,
D. G.
,
Laskowski
,
G. M.
, and
Tolpadi
,
A. K.
,
2012
, “
Experimental Measurements and Computational Predictions for an Internally Cooled Simulated Turbine Vane
,”
ASME J. Turbomach.
,
134
(
6
), p.
061005
.10.1115/1.4006282
9.
Pichon
,
Y.
,
2009
Turbulence Field Measurements for the Large Windtunnel
,” The University of Texas at Austin, Austin, TX, TTCRL Internal Report No. 2009.
10.
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
(
2
), pp.
231
237
.10.1115/1.1343457
11.
Moffat
,
R. J.
,
1988
, “
Describing the Uncertainties in Experimental Results
,”
Exp. Therm. Fluid Sci.
,
1
(
1
), pp.
3
17
.10.1016/0894-1777(88)90043-X
You do not currently have access to this content.