scholarly journals Numerical Modeling of Cyclic Creep-Fatigue Damage Development for Lifetime Assessment of Steam Turbine Components

2018 ◽  
Author(s):  
Mariusz Banaszkiewicz
Keyword(s):  
Numerical Modeling ◽  
Steam Turbine ◽  
Fatigue Damage ◽  
Cyclic Creep ◽  
Damage Development ◽  
Creep Fatigue

Analysis of Multi-Axial Creep–Fatigue Damage on an Outer Cylinder of a 1000 MW Supercritical Steam Turbine

2014 ◽  
Vol 136 (11) ◽  
Author(s):  
Weizhe Wang
Keyword(s):  
Steam Turbine ◽  
Fatigue Damage ◽  
Damage Mechanics ◽  
Hydrostatic Stress ◽  
Fatigue Behavior ◽  
Axial Stress ◽  
Outer Cylinder ◽  
Continuum Damage Mechanics ◽  
Transfer Coefficients ◽  
Creep Fatigue

A multi-axial continuum damage mechanics (CDM) model was proposed to calculate the multi-axial creep–fatigue damage of a high temperature component. A specific outer cylinder of a 1000 MW supercritical steam turbine was used in this study, and the interaction of the creep and fatigue behavior of the outer cylinder was numerically investigated under a startup–running–shutdown process. To this end, the multi-axial stress–strain behavior of the outer cylinder was numerically studied using Abaqus. The in-site measured temperatures were provided to validate the heat transfer coefficients, which were used to calculate the temperature field of the outer cylinder. The multi-axial mechanics behavior of the outer cylinder was investigated in detail, with regard to the temperature, Mises stress, hydrostatic stress, multi-axial toughness factor, multi-axial creep strain, and damage. The results demonstrated that multi-axial mechanics behavior reduced the total damage.

Micro-Mechanics of Creep-Fatigue Damage in PB-SN Solder Due to Thermal Cycling—Part I: Formulation

2002 ◽  
Vol 124 (3) ◽  
pp. 292-297 ◽  
Author(s):  
Pradeep Sharma ◽  
Abhijit Dasgupta
Keyword(s):  
Fatigue Damage ◽  
Damage Mechanics ◽  
Void Nucleation ◽  
Cyclic Creep ◽  
Diffusional Creep ◽  
Void Coalescence ◽  
Second Phase ◽  
Structural Stress ◽  
Damage Initiation ◽  
Creep Fatigue

This paper presents a micro-mechanistic approach for modeling fatigue damage initiation due to cyclic creep in eutectic Pb-Sn solder. Damage mechanics due to cyclic creep is modeled with void nucleation, void growth, and void coalescence model based on micro-structural stress fields. Micro-structural stress states are estimated under viscoplastic phenomena like grain boundary sliding, its blocking at second-phase particles, and diffusional creep relaxation. In Part II of this paper, the developed creep-fatigue damage model is quantified and parametric studies are provided to better illustrate the utility of the developed model.

Micro-Mechanics of Creep-Fatigue Damage in PB-SN Solder Due to Thermal Cycling—Part II: Mechanistic Insights and Cyclic Durability Predictions From Monotonic Data

2002 ◽  
Vol 124 (3) ◽  
pp. 298-304 ◽  
Author(s):  
Pradeep Sharma ◽  
Abhijit Dasgupta
Keyword(s):  
Fatigue Damage ◽  
Practical Interest ◽  
Cyclic Creep ◽  
Ramp Rate ◽  
Cyclic Durability ◽  
Creep Fatigue ◽  
Parametric Studies ◽  
Hydrostatic Stresses ◽  
Monotonic Test

This paper illustrates the micromechanics approach to cyclic creep-fatigue damage of Pb-Sn, developed by the authors with the help of a simple case study. It is demonstrated that durability predictions can be made based solely on monotonic test data. Various parametric studies of practical interest are conducted to obtain mechanistic insights into various aspects of damage in solders e.g., effect of hydrostatic stresses, grain size, ramp rate, etc.

Micro-Mechanics of Creep-Fatigue Damage in Pb-Sn Solder Due to Thermal Cycling

2000 ◽  
Author(s):  
Pradeep Sharma ◽  
Abhijit Dasgupta
Keyword(s):  
Fatigue Damage ◽  
Damage Mechanics ◽  
Void Nucleation ◽  
Cyclic Creep ◽  
Diffusional Creep ◽  
Void Coalescence ◽  
Structural Stress ◽  
Damage Initiation ◽  
Mechanical Cycling ◽  
Creep Fatigue

Abstract This paper presents a micro-mechanistic approach for modeling fatigue damage initiation due to cyclic creep in eutectic Pb-Sn solder. Damage mechanics due to cyclic creep is modeled with void nucleation, void growth and void coalescence model based on micro-structural stress fields. Micro-structural stress states are estimated under viscoplastic phenomena like grain boundary sliding and its blocking at 2nd phase particles, and diffusional creep relaxation. A conceptual framework is provided to quantify the creep-fatigue damage due to thermo-mechanical cycling. Some parametric studies are provided to better illustrate the utility of the developed model.

Semi-quantitative creep-fatigue damage analysis based on diffraction-based misorientation mapping and the correlation to macroscopic damage evolutions

2021 ◽  
pp. 106227
Author(s):  
Run-Zi Wang ◽  
Lv-Yi Cheng ◽  
Shun-Peng Zhu ◽  
Peng-Cheng Zhao ◽  
Hideo Miura ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Damage Analysis ◽  
Creep Fatigue ◽  
Fatigue Damage Analysis

scholarly journals On the creep fatigue and creep rupture behaviours of 9–12% Cr steam turbine rotor

2019 ◽  
Vol 76 ◽  
pp. 263-278 ◽  
Author(s):  
Xuanchen Zhu ◽  
Haofeng Chen ◽  
Fuzhen Xuan ◽  
Xiaohui Chen
Keyword(s):  
Steam Turbine ◽  
Turbine Rotor ◽  
Creep Rupture ◽  
Steam Turbine Rotor ◽  
Creep Fatigue

Creep-Fatigue damage analysis of modified 9Cr–1Mo steel based on a Voronoi crystalline model

2021 ◽  
pp. 104541
Author(s):  
Uijeong Ro ◽  
Sangyeop Kim ◽  
Yonghwi Kim ◽  
Moon Ki Kim
Keyword(s):  
Fatigue Damage ◽  
Damage Analysis ◽  
Creep Fatigue ◽  
Fatigue Damage Analysis

Creep-fatigue interaction on estimation of lifetime and fatigue damage of F82H

2021 ◽  
Vol 173 ◽  
pp. 112830
Author(s):  
Wenhai Guan ◽  
Hyoseong Gwon ◽  
Takanori Hirose ◽  
Hisashi Tanigawa ◽  
Yoshinori Kawamura ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Creep Fatigue

Management of Complex Loading Histories for Use in Probabilistic Creep-Fatigue Damage Assessments

2018 ◽  
Author(s):  
N. A. Zentuti ◽  
J. D. Booker ◽  
R. A. W. Bradford ◽  
C. E. Truman
Keyword(s):  
Fatigue Damage ◽  
Input Parameter ◽  
Three Dimensional ◽  
Complex Loading ◽  
Fe Model ◽  
Plant Component ◽  
Fatigue Lifetime ◽  
Wide Range ◽  
Stress Components ◽  
Creep Fatigue

An approach is outlined for the treatment of stresses in complex three-dimensional components for the purpose of conducting probabilistic creep-fatigue lifetime assessments. For conventional deterministic assessments, the stress state in a plant component is found using thermal and mechanical (elastic) finite element (FE) models. Key inputs are typically steam temperatures and pressures, with the three principal stress components (PSCs) at the assessment location(s) being the outputs. This paper presents an approach which was developed based on application experience with a tube-plate ligament (TPL) component, for which historical data was available. Though both transient as well as steady-state conditions can have large contributions towards the creep-fatigue damage, this work is mainly concerned with the latter. In a probabilistic assessment, the aim of this approach is to replace time intensive FE runs with a predictive model to approximate stresses at various assessment locations. This is achieved by firstly modelling a wide range of typical loading conditions using FE models to obtain the desire stresses. Based on the results from these FE runs, a probability map is produced and input(s)-output(s) functions are fitted (either using a Response Surface Method or Linear Regression). These models are thereafter used to predict stresses as functions of the input parameter(s) directly. This mitigates running an FE model for every probabilistic trial (of which there typically may be more than 104), an approach which would be computationally prohibitive.

Sign in / Sign up

Export Citation Format

Share Document