Establishing a methodology for resolving convective heat transfer from complex geometries

J. Ostanek, K. Thole, J. Prausa, A. Van Suetendael

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

Current turbine airfoils must operate at extreme temperatures, which are continuously driven higher by the demand for high output engines. Internal cooling plays a key role in the longevity of gas turbine airfoils. Ribbed channels are commonly used to increase heat transfer by generating turbulence and to provide a greater convective surface area. Because of the increasing complexity in airfoil design and manufacturing, a methodology is needed to accurately measure the convection coefficient of a rib with a complex shape. Previous studies that have measured the contribution to convective heat transfer from the rib itself have used simple rib geometries. This paper presents a new methodology to measure convective heat transfer coefficients on complex ribbed surfaces. The new method was applied to a relatively simple shape so that comparisons could be made with a commonly accepted method for heat transfer measurements. A numerical analysis was performed to reduce experimental uncertainty and to verify the lumped model approximation used in the new methodology. Experimental measurements were taken in a closed-loop channel using fully rounded, discontinuous, skewed ribs oriented 45° to the flow. The channel aspect ratio was 1.7:1 and the ratio of rib height to hydraulic diameter was 0.075. Heat transfer augmentation levels relative to a smooth channel were measured to be between 4.7 and 3 for Reynolds numbers ranging from 10,000 to 100,000.

Original languageEnglish (US)
Title of host publication2008 Proceedings of the ASME Turbo Expo
Subtitle of host publicationPower for Land, Sea, and Air
Pages1175-1186
Number of pages12
EditionPART B
DOIs
StatePublished - Dec 1 2008
Event2008 ASME Turbo Expo - Berlin, Germany
Duration: Jun 9 2008Jun 13 2008

Publication series

NameProceedings of the ASME Turbo Expo
NumberPART B
Volume4

Other

Other2008 ASME Turbo Expo
CountryGermany
CityBerlin
Period6/9/086/13/08

Fingerprint

Airfoils
Heat transfer
Geometry
Heat transfer coefficients
Gas turbines
Numerical analysis
Aspect ratio
Reynolds number
Turbulence
Turbines
Hydraulics
Engines
Cooling
Temperature

All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Ostanek, J., Thole, K., Prausa, J., & Suetendael, A. V. (2008). Establishing a methodology for resolving convective heat transfer from complex geometries. In 2008 Proceedings of the ASME Turbo Expo: Power for Land, Sea, and Air (PART B ed., pp. 1175-1186). (Proceedings of the ASME Turbo Expo; Vol. 4, No. PART B). https://doi.org/10.1115/GT2008-51411
Ostanek, J. ; Thole, K. ; Prausa, J. ; Suetendael, A. Van. / Establishing a methodology for resolving convective heat transfer from complex geometries. 2008 Proceedings of the ASME Turbo Expo: Power for Land, Sea, and Air. PART B. ed. 2008. pp. 1175-1186 (Proceedings of the ASME Turbo Expo; PART B).
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Ostanek, J, Thole, K, Prausa, J & Suetendael, AV 2008, Establishing a methodology for resolving convective heat transfer from complex geometries. in 2008 Proceedings of the ASME Turbo Expo: Power for Land, Sea, and Air. PART B edn, Proceedings of the ASME Turbo Expo, no. PART B, vol. 4, pp. 1175-1186, 2008 ASME Turbo Expo, Berlin, Germany, 6/9/08. https://doi.org/10.1115/GT2008-51411

Establishing a methodology for resolving convective heat transfer from complex geometries. / Ostanek, J.; Thole, K.; Prausa, J.; Suetendael, A. Van.

2008 Proceedings of the ASME Turbo Expo: Power for Land, Sea, and Air. PART B. ed. 2008. p. 1175-1186 (Proceedings of the ASME Turbo Expo; Vol. 4, No. PART B).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

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Ostanek J, Thole K, Prausa J, Suetendael AV. Establishing a methodology for resolving convective heat transfer from complex geometries. In 2008 Proceedings of the ASME Turbo Expo: Power for Land, Sea, and Air. PART B ed. 2008. p. 1175-1186. (Proceedings of the ASME Turbo Expo; PART B). https://doi.org/10.1115/GT2008-51411