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Title: Experimental investigation of airfoil trailing edge heat transfer and aerodynamic losses

Abstract

Modern gas turbine development is being driven by the often-incompatible goals of increased efficiency, better durability, and reduced emissions. High turbine inlet temperatures and ineffective cooling at the trailing edge of a first-stage stator vane lead to corrosion, oxidation, and thermal fatigue. Observations of this region in engines frequently reveal burn marks, cracks, and buckling. Fundamental studies of the importance of trailing edge heat transfer to the design of an optimal cooling scheme are scarce. An experimental study of an actively cooled trailing edge configuration, in which coolant is injected through a slot, is performed. Trailing edge heat transfer and aerodynamic measurements are reported. An optimum balance between maximizing blade row aerodynamic efficiency and improving thermal protection at the trailing edge is estimated to be achieved when blowing ratios are in the range between 2.1% and 2.8%. The thermal phenomena at the trailing edge are dominated by injection slot heat transfer and flow physics. These measured trends are generally applicable over a wide range of gas turbine applications. (author)

Authors:
 [1]; ;  [2];  [3]
  1. Sandia National Laboratories, Albuquerque, NM 87185 (United States)
  2. School of Mechanical Engineering, Maurice J. Zucrow Laboratories, Purdue University, West Lafayette, IN 47907 (United States)
  3. 132 Cecil Street SE, Minneapolis, MN 55414 (United States)
Publication Date:
OSTI Identifier:
20829602
Resource Type:
Journal Article
Resource Relation:
Journal Name: Experimental Thermal and Fluid Science; Journal Volume: 31; Journal Issue: 3; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING; GAS TURBINES; HEAT TRANSFER; AERODYNAMICS; LOSSES; VANES; STATORS; COOLING; DESIGN; EFFICIENCY

Citation Formats

Brundage, A.L., Plesniak, M.W., Lawless, P.B., and Ramadhyani, S. Experimental investigation of airfoil trailing edge heat transfer and aerodynamic losses. United States: N. p., 2007. Web. doi:10.1016/J.EXPTHERMFLUSCI.2006.04.004.
Brundage, A.L., Plesniak, M.W., Lawless, P.B., & Ramadhyani, S. Experimental investigation of airfoil trailing edge heat transfer and aerodynamic losses. United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.04.004.
Brundage, A.L., Plesniak, M.W., Lawless, P.B., and Ramadhyani, S. Mon . "Experimental investigation of airfoil trailing edge heat transfer and aerodynamic losses". United States. doi:10.1016/J.EXPTHERMFLUSCI.2006.04.004.
@article{osti_20829602,
title = {Experimental investigation of airfoil trailing edge heat transfer and aerodynamic losses},
author = {Brundage, A.L. and Plesniak, M.W. and Lawless, P.B. and Ramadhyani, S.},
abstractNote = {Modern gas turbine development is being driven by the often-incompatible goals of increased efficiency, better durability, and reduced emissions. High turbine inlet temperatures and ineffective cooling at the trailing edge of a first-stage stator vane lead to corrosion, oxidation, and thermal fatigue. Observations of this region in engines frequently reveal burn marks, cracks, and buckling. Fundamental studies of the importance of trailing edge heat transfer to the design of an optimal cooling scheme are scarce. An experimental study of an actively cooled trailing edge configuration, in which coolant is injected through a slot, is performed. Trailing edge heat transfer and aerodynamic measurements are reported. An optimum balance between maximizing blade row aerodynamic efficiency and improving thermal protection at the trailing edge is estimated to be achieved when blowing ratios are in the range between 2.1% and 2.8%. The thermal phenomena at the trailing edge are dominated by injection slot heat transfer and flow physics. These measured trends are generally applicable over a wide range of gas turbine applications. (author)},
doi = {10.1016/J.EXPTHERMFLUSCI.2006.04.004},
journal = {Experimental Thermal and Fluid Science},
number = 3,
volume = 31,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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