Influence of high-temperature dwell time on creep-fatigue behavior in a 1000 MW steam turbine rotor
| Autor: | Patrick Buhl, Weizhe Wang, Andreas Klenk, Yingzheng Liu |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
geography
Materials science geography.geographical_feature_category Viscoplasticity business.industry Mechanical Engineering Constitutive equation 02 engineering and technology Structural engineering 021001 nanoscience & nanotechnology Inlet Dwell time 020303 mechanical engineering & transports 0203 mechanical engineering Creep Mechanics of Materials Phase (matter) General Materials Science Composite material Deformation (engineering) 0210 nano-technology business Groove (music) |
| Zdroj: | Engineering Fracture Mechanics. 166:1-22 |
| ISSN: | 0013-7944 |
| DOI: | 10.1016/j.engfracmech.2016.08.018 |
| Popis: | Creep-fatigue behavior at different dwell times was numerically investigated for a 1000 MW steam turbine rotor. Fixed iterations of the startup-running-shutdown process were chosen, and the dwell time of the running phase was changed to study the effect of dwell time on creep-fatigue behavior. Toward this end, a viscoplastic constitutive model with damage was presented to describe creep-fatigue deformation behavior. Multiaxial creep-fatigue tests and thermo-mechanical fatigue tests were conducted to validate the material model. Good agreement was achieved between the simulated and measured results. Analysis of the temperature field disclosed three phases: a warming phase, a transition phase, and an elevated temperature phase. The damage evolution at five locations was compared, and the results showed that the creep damage at the blade groove (thermo-mechanical-load dominated structure) and fatigue damage at the inlet notch zone (thermal-stress dominated structure) were more significant than those at other locations. Specific investigation of the dwell time on the creep-fatigue damage was performed in terms of creep damage, fatigue damage, and accumulated plastic strains. The results revealed that the dwell time significantly accelerated the creep damage at the blade groove and the fatigue damage at the inlet notch zone. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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