0
Research Papers

Film Cooling With a Thermal Barrier Coating: Round Holes, Craters, and Trenches

[+] Author and Article Information
F. Todd Davidson

e-mail: davidsonft@gmail.com

David A. KistenMacher

e-mail: dkistenmacher@gmail.com

David G. Bogard

e-mail: dbogard@mail.utexas.edu
The University of Texas at Austin,
Austin, Texas 78712

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the Journal of Turbomachinery. Manuscript received May 14, 2013; final manuscript received June 6, 2013; published online September 26, 2013. Editor: Ronald Bunker.

J. Turbomach 136(4), 041007 (Sep 26, 2013) (11 pages) Paper No: TURBO-13-1075; doi: 10.1115/1.4024883 History: Received May 14, 2013; Revised June 06, 2013

Little work has been done to understand the interconnected nature of film cooling and thermal barrier coatings (TBCs) on protecting high temperature turbine components. With increasing demands for improved engine performance it is vital that a greater understanding of the thermal behavior of turbine components is achieved. The purpose of this study was to investigate how various film cooling geometries affect the cooling performance of a thermally conducting turbine vane with a TBC. The vane model used in this study was designed to match the thermal behavior of real engine components by properly scaling the convective heat transfer coefficients along with the thermal conductivity of the vane wall. This allowed for the measurement of temperatures at the interface of the TBC and vane wall which, when nondimensionalized, are representative of the temperatures present for actual engine vanes. This study found that the addition of a TBC on the surface of an internally cooled vane produced a near constant cooling performance despite significant changes in the blowing ratio. The craters, trench, and modified trench of this study were found to provide much better film cooling coverage than round holes; however, the improved film cooling coverage led to only slight improvements in temperature at the interface of the TBC and vane wall. These results suggest that there is minimal advantage in using more complicated cooling configurations, particularly since they may be more susceptible to TBC spallation. However, the improved film coverage from the trench and crater designs may increase the life of the TBC, which would be greatly beneficial to the long-term thermal protection of the vane.

Copyright © 2014 by ASME
Your Session has timed out. Please sign back in to continue.

References

Bogard, D. G., and Thole, K. A., 2006, “Gas Turbine Film Cooling,” J. Propul. Power, 22, pp. 249–270. [CrossRef]
Dees, J. E., Ledezma, G. A., Bogard, D. G., and Laskowski, G. M., 2013, “Overall and Adiabatic Effectiveness Values on a Scaled Up, Simulated Gas Turbine Vane,” ASME J. Turbomach., 135(5), p. 051017. [CrossRef]
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 [CrossRef].
Maikell, J., Bogard, D., Piggush, J., and Kohli, A., 2010, “Experimental Simulation of a Film Cooled Turbine Blade Leading Edge Including Thermal Barrier Coating Effects,” ASME J. Turbomach., 133(1), p. 011014 [CrossRef].
Davidson, F. T., Dees, J. E., and Bogard, D. G., 2011, “An Experimental Study of Thermal Barrier Coatings and Film Cooling on an Internally Cooled Simulated Turbine Vane,” ASME Turbo Expo, Vancouver, Canada, June 6–10, ASME Paper No. GT2011-46604. [CrossRef]
Waye, S. K., and Bogard, D. G., 2007, “High Resolution Film Cooling Effectiveness Measurements of Axial Holes Embedded in a Transverse Trench With Various Trench Configurations,” ASME J. Turbomach., 129(2), pp. 202–211. [CrossRef]
Bunker, R., 2002, “Film Cooling Effectiveness Due to Discrete Holes Within a Transverse Surface Slot,” IGTI Turbo Expo, Amsterdam, Netherlands, June 3–6, ASME Paper No. GT2002-30178. [CrossRef]
Dorrington, J. R., Bogard, D. G., and Bunker, R. S., 2007, “Film Effectiveness Performance for Coolant Holes Embedded in Various Shallow Trench and Crater Depressions,” ASME Paper No. GT2007-27992. [CrossRef]
Bunker, R. S., 2001, “A Method for Improving the Cooling Effectiveness of a Gaseous Coolant Stream,” U.S. Patent No. 6,234,755.
Fric, T. F., and Campbell, R. P., 2002, “Method for Improving the Cooling Effectiveness of a Gaseous Coolant Stream Which Flows Through a Substrate and Related Articles of Manufacture,” U.S. Patent No 6,383,602.
Albert, J. E., 2011, “Experimental Simulation and Mitigation of Contaminant Deposition on Film Cooled Gas Turbine Airfoils,” Ph.D. dissertation, University of Texas at Austin, Austin, TX, pp. 275.
Ethridge, M. I., Cutbirth, J. M., and Bogard, D. G., 2000, “Effects of Showerhead Cooling on Turbine Vane Suction Side Film Cooling Effectiveness,” ASME IMECE Conference, Orlando, FL, November 5–10.
Davidson, F. T., 2012, “An Experimental Study of Film Cooling, Thermal Barrier Coatings and Contaminant Deposition on an Internally Cooled Turbine Airfoil Model,” Ph.D. dissertation, University of Texas at Austin, Auston, TX, pp. 12, 62, 89.
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. 061003. [CrossRef]
Shih, T., Chi, K., Ramachandran, P., Ames, R., and Dennis, R., 2010, “The Role of the Biot Number in Turbine-Cooling Design and Analysis,” 2010 University Turbine Systems Research (UTSR) Workshop on Heat Transfer, October 19–21.
Bunker, R. S., 2009, “The Effects of Manufacturing Tolerances on Gas Turbine Cooling,” ASME J. Turbomach., 131(4), p. 041018. [CrossRef]
Feuerstein, A., Knapp, J., Taylor, T., Ashary, A., Bolcavage, A., and Hitchman, N., 2008, “Technical and Economical Aspects of Current Thermal Barrier Coating Systems for Gas Turbine Engines by Thermal Spray and EBPVD: A Review,” J. Therm. Spray Technol., 17(2), pp. 199–213. [CrossRef]
Padture, N. P., Gell, M., and Jordan, E. H., 2002, “Thermal Barrier Coatings for Gas-Turbine Engine Applications,” Science, 296, pp. 280–284. [CrossRef] [PubMed]
Soechting, F. O., 1999, “A Design Perspective on Thermal Barrier Coatings,” J. Therm. Spray Technol., 8(4), pp. 505–511. [CrossRef]
Special Metals Corporation, 2004, “Inconel® Alloy X-750 Data Sheet,” Publication No. SMC-067, www.specialmetals.com
Rigney, D. V., Viguie, R., Wortman, D. J., and Skelly, D. W., 1997, “PVD Thermal Barrier Coating Applications and Process Development for Aircraft Engines,” J. Therm. Spray Technol., 6(2), pp. 167–175. [CrossRef]
Kline, S. J. and McClintock, F.A., 1953, “Describing Uncertainties in Single Sample Experiments,” Mech. Eng. (Am. Soc. Mech. Eng.), 75, pp. 3–8.
Moffat, R. J., 1988, “Describing the Uncertainties in Experimental Results,” J. Therm. Fluid Sci., 1, pp. 3–17. [CrossRef]
Davidson, F. T., Kistenmacher, D. A., and Bogard, D. G., 2012, “A Study of Deposition on a Turbine Vane With a Thermal Barrier Coating and Various Film Cooling Geometries,” ASME Paper No. GT2012-70033. [CrossRef]
Dees, J. E., Bogard, D. G., Ledezma, G. A., Laskowski, G. M., and Tolpadi, A. K., 2010, “Experimental Measurements and Computational Predictions for an Internally Cooled Simulated Turbine Vane With 90 Degree Rib Turbulators,” ASME J. Turbomach., 134(6), pp. 061005. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Schematic of turbine vane test section

Grahic Jump Location
Fig. 2

Schematic of secondary flow loop

Grahic Jump Location
Fig. 3

Test airfoil schematic

Grahic Jump Location
Fig. 4

Vane cross-section and s/d locations

Grahic Jump Location
Fig. 5

Schematics of the various pressure side cooling hole designs

Grahic Jump Location
Fig. 6

Photographs of interface thermocouples prior to applying the simulated TBC to the vane surface

Grahic Jump Location
Fig. 7

Vane wall cross-section with the TBC and relative location of measurements of interest

Grahic Jump Location
Fig. 8

Comparison of ϕ with and without the TBC for round holes with an active showerhead (M listed here is for only the pressure side holes)

Grahic Jump Location
Fig. 9

Comparison of laterally averaged τ for round holes with an active showerhead at varying blowing ratios

Grahic Jump Location
Fig. 10

Contour plots of τ for round holes with an active showerhead

Grahic Jump Location
Fig. 11

Effect of the blowing ratio on ϕ for varying film cooling designs

Grahic Jump Location
Fig. 12

Effect of the cooling design on ϕ for varying blowing ratios

Grahic Jump Location
Fig. 13

Effect of the cooling design on ϕ for varying blowing ratios

Grahic Jump Location
Fig. 14

Effect of the blowing ratio on τ for varying film cooling designs

Grahic Jump Location
Fig. 15

Effect of the blowing ratio on τ for varying film cooling designs

Grahic Jump Location
Fig. 16

Contour plots of τ for varying film cooling designs at M = 0.5 and M = 1.0

Grahic Jump Location
Fig. 17

Contour plots of τ for varying film cooling designs at M = 2.0 and M = 5.0

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In