Abstract

Low cycle fatigue (LCF) of jet engine disks is a major contributor to the maintenance costs of an engine. The current industry standard for the analysis of LCF is to use representative flight missions to reflect the in-service usage of engines. Based on the engine performance during those missions, the internal stresses and temperatures of life-critical components are calculated. These stresses and temperatures define the cyclic life consumption of a mission and determine the certifiable LCF life of the engine. The engine performance is defined by the power setting schedules of the engine, so-called engine ratings. The effect of the rated climb performance on high pressure turbine (HPT) disk life is investigated for a generic two-shaft engine operated in a small twin-jet civil aircraft. LCF life is analyzed using a finite element (FE)-based cycle counting model. The aircraft climb performance resulting from the changed climb ratings is assessed with an aircraft performance model. It is shown that there are climb ratings which result in reduced LCF life consumption and climb time compared to the reference rating. Employing these ratings on in-service engines increases the certifiable life count and reduces maintenance costs.

References

References
1.
Bagnall
,
S. M.
,
Shaw
,
D. L.
, and
Mason-Flucke
,
J. C.
,
1999
, “
Implications of ‘Power by the Hour’ on Turbine Blade Lifing
,”
RTO AVT Specialists' Meeting
, Ottawa, ON, Canada, Oct. 21–22, Paper No. RTO MP-37.
2.
Devereux
,
B.
, and
Singh
,
R.
,
1994
, “
Use of Computer Simulation Techniques to Assess Thrust Rating as a Means of Reducing Turbo-Jet Life Cycle Costs
,”
ASME
Paper No. 94-GT-269. 10.1115/94-GT-269
3.
Montgomery
, III
,
J.
,
Sewall
,
T.
, and
Batka
,
J.
,
1983
, “
Aircraft Usage and Effects on Engine Life
,”
ASME
Paper No. 83-GT-143.
4.
EASA
,
2015
, “
Certification Specification and Acceptable Means of Compliance for Engines
,” European Union Aviation Safety Agency, Cologne, Germany, CS-E, Amendm. 4.
5.
Eady
,
C.
,
2000
, “
Modes of Gas Turbine Component Life Consumption
,” Recommended Practices for Monitoring Gas Turbine Engine Life Consumption, NATO, Paris, France, Report No. RTO-TR-028.
6.
Beres
,
W.
,
2000
, “
Mechanics of Material Failure
,” Recommended Practices for Monitoring Gas Turbine Engine Life Consumption, NATO, Paris, France, Report No. RTO-TR-028.
7.
Hanumanthan
,
H.
,
Stitt
,
A.
,
Laskaridis
,
P.
, and
Singh
,
R.
,
2012
, “
Severity Estimation and Effect of Operational Parameters for Civil Aircraft Jet Engines
,”
Proc. Inst. Mech. Eng., Part G
,
226
(
12
), pp.
1544
1561
.10.1177/0954410011424854
8.
Davenport
,
O.
,
2000
, “
Maintenance Policies and Procedures
,” Recommended Practices for Monitoring Gas Turbine Engine Life Consumption, NATO, Paris, France, Report No. RTO-TR-028.
9.
Harrison
,
G.
,
2000
, “
Translation of Service Usage into Component Life Consumption
,” Recommended Practices for Monitoring Gas Turbine Engine Life Consumption, NATO, Paris, France, Report No. RTO-TR-028.
10.
Haibach
,
E.
,
2006
,
Betriebsfestigkeit
, 3rd ed.,
Springer-Verlag
,
Berlin Heidelberg, New York
.
11.
Eshelby
,
M.
,
2000
,
Aircraft Performance
,
Arnold
,
London
.
12.
Mair
,
W. A.
, and
Birdsall
,
D. L.
,
1992
,
Aircraft Performance
,
Cambridge University Press
,
Cambridge, UK
.
13.
Torenbeek
,
E.
, 2013,
Synthesis of Subsonic Airplane Design
, Wiley, Chichester, UK.
14.
Jenkinson
,
L. R.
,
Simpkin
,
P.
, and
Rhodes
,
D.
,
1999
,
Civil Jet Aircraft Design
,
Arnold
,
London, UK
.
15.
Bartel
,
M.
,
2007
, “
Simplified Thrust and SFC Calculations of
Modern Two-Shaft Turbofan Engines for Preliminary Aircraft Design,”
AIAA
Paper No. 2007–7847.10.2514/6.2007-7847
16.
Cumpsty
,
N. A.
,
2010
, “
Preparing for the Future: Reducing Gas Turbine Environmental Impact—IGTI Scholar Lecture
,”
ASME J. Turbomach.
,
132
(
4
), p.
041017
.10.1115/1.4001221
17.
Gunn
,
P. D.
,
Herald
,
R. A.
,
Martindale
,
I. C.
, and
Paulson
,
C. V.
,
1999
, “
Method and Apparatus for Automatically Providing Jet Engine Thrust Ratings to Avionic Systems
,” U. S. Patent No. 5,893,040.
18.
Saarlas
,
M.
,
2007
,
Aircraft Performance
,
Wiley
,
Hoboken, NJ
.
19.
Young
,
T. M.
,
2018
,
Performance of the Jet Transport Airplane
,
Wiley
, Hoboken, NJ.
20.
Cohen
,
H.
,
Rogers
,
G. F. C.
, and
Saravanamuttoo
,
H. I. H.
,
1996
,
Gas Turbine Theory
, 4th ed.,
Longman Group Limited
,
Essex, UK
.
21.
Naeem
,
M.
,
Singh
,
R.
, and
Probert
,
D.
,
1999
, “
Implications of Engine Deterioration for a High-Pressure Turbine-Blade's Low-Cycle Fatigue (LCF) Life-Consumption
,”
Int. J. Fatigue
,
21
(
8
), pp.
831
847
.10.1016/S0142-1123(99)00025-0
22.
Shanmuganathan
,
V.
,
Haran
,
A.
, and
Gayathri
,
N.
,
2015
, “
Condition Monitoring Maintenance of Aero-Engines Through LUMS—A Method for the Implementation of Lean Tools
,”
Measurement
,
73
, pp.
226
230
.10.1016/j.measurement.2015.05.017
23.
Walker
,
K.
,
1970
, “
The Effect of Stress Ratio During Crack Propagation and Fatigue for 2024-T3 and 7075-T6 Aluminum
,”
Effects of Environment and Complex Load History on Fatigue Life
,
ASTM International
,
Philadelphia, PA
.
24.
Dowling
,
N. E.
,
Calhoun
,
C. A.
, and
Arcari
,
A.
,
2009
, “
Mean Stress Effects in Stress-Life Fatigue and the Walker Equation
,”
Fatigue Fract. Eng. Mater. Struct.
,
32
, pp.
163
179
.10.1111/j.1460-2695.2008.01322.x
25.
Miner
,
M. A.
,
1945
, “
Cumulative Damage in Fatigue
,”
ASME J. Appl. Mech.
, 12, pp.
159
164
.
26.
Pfoertner
,
H.
,
2000
, “
Extension of the Usable Engine Life by Modelling and Monitoring. Aging Aircraft Fleets: Structural and Other Subsystem Aspects
,” RTO AVT Lecture Series, MTU Aero Engines GmbH, Sofia, Bulgaria, Report No. RTO EN-015.
27.
Koehl
,
M.
,
2001
, “
Algorithmic Aero Engine Life Usage Monitoring Based on Reference Analysis of Design Mission
,”
Third International Workshop on Structural Health Monitoring
, Stanford, CA.
28.
Schulz
,
J.
,
2018
, “
Untersuchung der Lebensdauererwartung von Turbinenscheiben anhand von Schädigungsanalysen aufgezeichneter Flugmissionen
,” Master's thesis, Technical University of Berlin, Germany.
29.
Scheiderer
,
J.
,
2008
,
Angewandte Flugleistung
,
Springer-Verlag
,
Berlin Heidelberg
.
30.
Boeing
,
1989
,
Jet Transport Performance Methods
, 7th ed.,
Boeing
,
Seattle, Washington, DC
.
31.
ESDU
,
2005
, “
Acceleration Factors for Climb and Descent Rates at Constant EAS, CAS
,” IHS ESDU, London, UK, Report No. M. 2005-02 81046.
32.
El-Soueidan
,
M.
,
2018
, “
Untersuchungen zum Einfluss von Climb-Ratings auf die Lebensdauererwartung von Turbinenscheiben
,” Bachelor's thesis, Technical University of Berlin, Berlin, Germany.
33.
Williams
,
D. T.
,
Smout
,
P.
,
Bianchi
,
M.
, and
Joinson
,
M. B.
,
2013
, “
The Use of Probabilistic Methods in Determining Turbine Disc Cyclic Life Uncertainty
,”
ASME
Paper No. GT2013-94972. 10.1115/GT2013-94972
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