Thermomechanical stresses in gas turbine blades are investigated. Attention is focused on effects caused by varying the cooling airflow that runs through the blade interior, keeping constant a mainstream condition around the blade surface. Stress concentration was predicted numerically under engine real operating conditions. Temperature distributions in the metal blade surface produced by convective boundary conditions were linked with heat conduction within the blade using a conjugate solution. Results of stress concentration in the blade material for reduced cooling flow rate, blocked cooling ducts, and rotation rate were obtained. It is shown that temperature and stress distributions are a strong function of position in blade interior material and surface. Thermomechanical stress concentration was observed in the leading edge, with the endwall region affected by large stress concentration. Stress magnitude increments were found for combined cyclic thermal heating and sustained mechanical loads on specific planes of airfoil span for reduced cooling flow. Also, large stress gradients between leading and trailing regions of the blade were observed. The study reveals that blocking channels increase stresses in the central region of blade transversal cross section.

References

References
1.
Cunha
,
F. J.
,
Seetharaman
,
V.
, and
Chyu
,
M. K.
,
2006
, “
Thermal-Mechanical Life Prediction System for Coated Anisotropic Turbine Components
,”
ASME
Paper No. GT2006-9101710.1115/GT2006-91017.
2.
Arnal
,
M.
,
Precht
,
Ch.
, and
Sprunk
,
T.
,
2007
, “
Fluid Structure Interaction for Cool Gas Turbine Blades
,”
ANSYS Advantage
,
1
, pp.
6
8
.
3.
Ogata
,
T.
, and
Yamamoto
,
M.
,
2006
, “
Biaxial Thermomechanical Fatigue Life Property of a Ni Base DS Super Alloy
,”
ASME
Paper No. GT2006-90758.10.1115/GT2006-90758
4.
Ieronymidis
,
I.
,
Gillespie
,
R. H.
, and
Ireland
,
P. T.
,
2006
, “
Detailed Heat Transfer Measurements in a Model of an Integrally Cast Cooling Passage
,”
ASME
Paper No. GT2006-91231.10.1115/GT2006-91231
5.
Cuhna
,
F. J.
,
Dahmer
,
M. T.
, and
Chyu
,
M. K.
,
2005
, “
Analysis of Airfoil Trailing Edge Heat Transfer and Its Significance in Thermal-Mechanical Design and Durability
,”
ASME
Paper No. GT2005-68108.10.1115/GT2005-68108
6.
Cuhna
,
F. J.
,
Dahmer
,
M. T.
, and
Chyu
,
M. K.
,
2005
, “
Thermal-Mechanical Life Prediction System for Anisotropic Turbine Components
,”
ASME
Paper No. GT2005-68107.10.1115/GT2005-68107
7.
Fluent, Inc.
,
2001
,
Fluent V6.3 User's Guide, Vol. 3
,
Fluent Inc.
,
Canterra Resource Park, Lebanon, NH
.
8.
Bohn
,
D.
,
Ren
,
J.
, and
Kusterer
,
K.
,
2003
, “
Conjugate Heat Transfer Analysis for Film Cooling Configurations for Different Hole Diameters
,”
ASME
Paper No. GT2003-38369.10.1115/GT2003-38369
9.
Bohn
,
D.
,
Wolff
,
A.
,
Wolff
,
M.
, and
Kusterer
,
K.
,
2002
, “
Experimental and Numerical Investigation of a Steam-Cooled Vane
,”
ASME
Paper No. GT2002-30210.10.1115/GT2002-30210
10.
Campos-Amezcua
,
A.
,
Mazur-Czerwiec
,
Z.
, and
Gallegos-Muñoz
,
A.
,
2011
, “
Thermomechanical Transient Analysis and Conceptual Optimization of a First Stage Bucket
,”
ASME J. Turbomach.
,
133
, p.
011031
.10.1115/1.4001367
11.
Gatski
,
T. B.
,
Hussaini
,
M. Y.
, and
Lumley
,
J. L.
,
1996
,
Simulation and Modeling of Turbulent Flows
,
Oxford University Press
,
New York
.
12.
Celick
,
I. B.
,
Ghia
,
U.
,
Roache
,
P. J.
, and
Christopher
,
R.
,
2008
, “
Procedure for Estimation and Reporting of Uncertainty Due to Discretization in CFD Applications
,”
ASME J. Fluids Eng.
,
130
, p.
078001
.10.1115/1.2960953
13.
Ansys Inc.
,
2008
, “
ANSYS User's Guide
,”
Ansys Inc.
,
Ann Arbor, MI
.
14.
Sierra
,
F. Z.
,
Narzary
,
D.
,
Bolaina
,
C.
,
Han
,
J. C.
,
Kubiak
,
J.
, and
Nebradt
,
J.
,
2009
, “
Heat Transfer and Thermal Mechanical Stress Distributions in Gas Turbine Blades
,”
ASME
Paper No. GT2009-59194.10.1115/GT2009-59194
15.
Teloxa
,
J.
,
Carrillo
,
F.
,
Bolaina
,
C.
,
Varela
,
C.
, and
Sierra
,
F. Z.
,
2013
, “
Experimental and Numerical Study of Gap Size and Cooling Flow Rate Effects on the Tip Flow of Gas Turbine Blades
,”
Int. J. Turbo Jet Engines
,
30
(
1
), pp.
111
122
10.1515/tjj-2012-0022.
16.
Han
,
J. C.
,
Dutta
,
S.
, and
Ekkad
,
S. V.
,
2000
,
Gas Turbine Heat Transfer and Cooling Technology
,
Taylor & Francis
,
New York
.
17.
Mase
,
G.
, and
Mase
,
T.
,
1992
,
Continuum Mechanics for Engineers
,
CRS Press
,
Boca Raton, FL
.
18.
Lai
,
M.
,
Rubin
,
D.
, and
Krempl
,
E.
,
1978
,
Introduction to Continuum Mechanics
,
Pergamon Inc
,
Oxford, UK
.
19.
Bolaina
,
C.
,
2010
, “
Analysis of the Thermo-Mechanical Stress Distributions in a Gas Turbine Blade (in Spanish)
,” Ph.D. thesis,
Universidad Autónoma del Estado de Morelos
,
Cuernavaca, Mexico
.
20.
ASM International
,
1990
,
ASM Handbook Vol. 1. Properties and Selection: Irons Steels and High Performance Alloys
,
ASM International
,
Novelty, OH
.
You do not currently have access to this content.