This paper is aimed to show the effects of partial stall on the fracture of the first stage rotating blades of the gas turbine compressors of an onshore gas refinery. The first part of the paper deals with the results of finite element modeling (FEM) of stress distribution and stress concentration areas on the blades under its first to third natural frequencies. Comparison of the stress concentration areas with the fractured blades shows that the blades have been fractured due to resonance under the first and second natural frequencies. The second part of the paper deals with the computational fluid dynamics (CFD) simulation of air flowing through the blades to determine the most probable sources of vibrational loads as the aerodynamic forces. Results of CFD simulations show that the operation of the gas turbines under 40–50% of their nominal output power—which has been very regular in the history of operation of the turbines—increases the possibility of stall at the tip side of the first stages rotating blades. The vortices shedding due to downwash flow at the tip side of the blades causes flow instability and increases the aerodynamic vibrational forces on the blades, which finally makes them to experience a kind of high cycle fatigue (HCF).

References

References
1.
Nandi
,
D.
, and
Murty
,
K. R. C.
,
2014
, “
Failure of 9FA Gas Turbine Compressor—A Unique Experience
,” Technical Report, accessed Dec. 26,
2014
, http://www.infraline.com/power/presentations/others/ntpc/N_89%20Failure%20of%209FA%20Gas%20Turbine-%20A%20Unique%20Exp.D.Nandi.pdf
2.
Poursaeidi
,
E.
,
Babaei
,
A.
,
Behrouzshad
,
F.
, and
Mohammadi Arhani
,
M. R.
,
2013
, “
Failure Analysis of an Axial Compressor First Row Rotating Blades
,”
Eng. Failure Anal.
,
28
, pp.
25
33
.
3.
Rama Rao
,
A.
, and
Dutta
,
B. K.
,
2012
, “
Vibration Analysis for Detecting Failure of Compressor Blade
,”
Eng. Failure Anal.
,
25
, pp.
211
218
.
4.
Farrahi
,
G. H.
,
Tirehdast
,
M.
,
Masoumi Khalil Abad
,
E.
,
Parsa
,
S.
, and
Motakefpoor
,
M.
,
2011
, “
Failure Analysis of a Gas Turbine Compressor
,”
Eng. Failure Anal.
,
18
(
1
), pp.
474
484
.
5.
Kermanpur
,
A.
,
2008
, “
Failure Analysis of Gas Turbine Compressor Blade
,”
Eng. Failure Anal.
,
15
(
8
), pp.
1052
1064
.
6.
Lourenco
,
N. J.
,
2008
, “
Fatigue Failure of a Compressor Blade
,”
Eng. Failure Anal.
,
15
(
8
), pp.
1150
1154
.
7.
Yoon
,
W. N.
,
Kang
,
M. S.
,
Jung
,
N. K.
,
Kim
,
J. S.
, and
Choi
,
B. H.
,
2012
, “
Failure Analysis of the Defect-Induced Blade Damage of a Compressor in the Gas Turbine of a Cogeneration Plant
,”
Int. J. Precis. Eng. Manuf.
,
13
(
5
), pp.
717
722
.
8.
Cowls
,
B. A.
,
1996
, “
High Cycle Fatigue in Aircraft Gas Turbines—An Industry Perspective
,”
Int. J. Fract.
,
80
(
2–3
), pp.
147
193
.
9.
Poursaeidi
,
E.
,
Babaei
,
A.
,
Mohammadi Arhani
,
M. R.
, and
Arablu
,
M.
,
2012
, “
Effects of Natural Frequencies on the Failure of R1 Compressor Blades
,”
Eng. Failure Anal.
,
25
, pp.
304
315
.
10.
Poursaeidi
,
E.
, and
Arablu
,
M.
,
2013
,
Humidity Effects on Corrosion-Assisted Fatigue Fracture of Heavy-Duty Gas Turbine Compressor Blades
,”
AIAA J. Propul. Power
,
29
(
5
), pp.
1009
1016
.
11.
Combustion Turbine Operations Task Force, 2007, “
CTOTF Tackles the Tough Issues, Including 7FA R0 and Mid-Compressor Failures
,” Combined Cycle Journal, First Quarter, 2007, accessed Feb. 11,
2012
, http://www.combinedcyclejournal.com/webroot/1Q2007/107,%20p%2072-92%20 CTOTF.pdf
12.
Brokaw
,
M.
,
2005
, “
6B Compressor
,” GE Energy Technical/User's Conference, League City, TX, Aug. 28–31, accessed Nov. 5, 2014, http://www.frame6usersgroup.org/frame6usersgroup/Presentations/2005/6B%20Compressor%20Matt%20Brokaw%20GE%20Energy%20Frm6UG05.pdf
13.
Poursaeidi
,
E.
, and
Mohammadi Arhani
,
M. R.
,
2010
, “
Failure Investigation of an Auxiliary Steam Turbine
,”
Eng. Failure Anal.
,
17
(
6
), pp.
1328
1336
.
14.
Palmer
,
C. A.
, and
Erbes
,
M. R.
,
1994
, “
Simulation Methods Used to Analyze the Performance of the GE PG6541b Gas Turbine Utilizing Low Heating Value Fuels
,”
ASME Cogeneration Turbo Power
,
Portland, OR
, Oct. 25–27.
15.
Hah
,
C.
,
2007
, “
Flow Instabilities and Non-Synchronous Vibration in a Compressor
,”
8th International Symposium on Experimental and Computational Aerothermodynamics of Internal Flows
(
ISAIF
),
Lyon
, July 2–6.
You do not currently have access to this content.