RESEARCH PAPER
Applicability of Notch Stress-Strain Correction Methods to Low-Cycle Fatigue Life Prediction of Turbine Rotors Subjected to Thermomechanical Loads
1
Energy Conversion Department, The Szewalski Institute of Fluid-Flow Machinery, Polish Academy of Sciences, Fiszera 14, 80-231 Gdańsk, Poland
2
Faculty of Technical Sciences, Department of Mechanics and Machine Design, University of Warmia and Mazury, Oczapowskiego 2, 10-719 Olsztyn, Poland
Submission date: 2017-04-05
Acceptance date: 2018-07-26
Online publication date: 2018-10-16
Publication date: 2018-09-01
Acta Mechanica et Automatica 2018;12(3):179-185
KEYWORDS
ABSTRACT
The paper analyses the possibility of using analytical methods of notch stress-strain correction in low-cycle fatigue life predictions of steam turbine rotors operating under non-isothermal conditions. The assessment was performed by comparing strain amplitudes calculated using the Neuber and Glinka-Molski methods and those predicted by the finite element analysis (FEA) employing elastic-plastic material model. The results of investigations reveal that the Neuber method provides an upper bound limit, while the Glinka-Molski method results in a lower bound limit of strain amplitude. In the case of rotor heat grooves, both methods provide equally accurate results of notch strain amplitude and are suited to estimating lower and upper bound limits of low-cycle fatigue life under non-isothermal conditions.
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| eISSN: | 2300-5319 |
| ISSN: | 1898-4088 |
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