scholarly journals Improved numerical model for fatigue cumulative damage of mechanical structure considering load sequence and interaction

2021 ◽  
Vol 13 (2) ◽  
pp. 168781402199530
Author(s):  
Bixiong Huang ◽  
Shuci Wang ◽  
Shuanglong Geng ◽  
Xintian Liu
Keyword(s):  
Fatigue Life ◽  
Theoretical Basis ◽  
Life Prediction ◽  
Damage Model ◽  
Cumulative Damage ◽  
Load Spectrum ◽  
Random Load ◽  
Mechanical Parts ◽  
Proposed Model ◽  
Load Sequence

To more accurately predict the fatigue life of components under the action of random loads, it is necessary to explore the influence of the interaction between the load sequence and the load on the life prediction. Based on the Manson-Halford method and Corten-Dolan model, this paper establishes a fatigue cumulative damage model that takes into account both the load order and the interaction between loads, and also takes into account the loads near the fatigue limit. The fatigue life of mechanical parts under random load can be calculated through this model, which provides a theoretical basis for life prediction under random load spectrum. The fatigue life of mechanical parts under random load can be calculated through this model, which provides a theoretical basis for life prediction under random load spectrum. Comparing the calculation results of the proposed model with the results of Palmgren Miner, Manson-Halford method, and Corten-Dolan model, it is found that the fatigue damage model established can reasonably predict the fatigue life of parts. Comparison and verification of examples further prove the accuracy and reliability of the proposed model.

Development and Validation of a S-N Based Two Phase Bending Fatigue Life Prediction Model

2001 ◽  
Author(s):  
Avinash Singh
Keyword(s):  
Fatigue Life ◽  
Life Prediction ◽  
Damage Model ◽  
Cumulative Damage ◽  
Fatigue Life Prediction ◽  
Two Phase ◽  
Initiation Phase ◽  
Two Phases ◽  
Life Predictions ◽  
Development And Validation

Abstract The stress-life (S-N) method along with the Palmgren-Miner cumulative damage theory is the simplest and the most commonly used fatigue life prediction technique. Its main advantage is that the material properties needed are easy to collect and life calculation is simple. However under many variable amplitude loading conditions, life predictions have been found to be unreliable. Various modifications have been proposed to the Palmgren-Miner theory, but they have not lead to more reliable life predictions. In this paper, a two-stage cumulative damage model will be developed and validated. This model divides fatigue life into two phases — a crack initiation phase and a crack propagation phase. It will be shown that the proposed method results in greatly improved life prediction capabilities. Also, the proposed method retains the simplicity of the S-N based approach in that the material data is still relatively simple to generate and the calculations are straightforward.

Probabilistic fatigue life prediction and reliability assessment of a high pressure turbine disc considering load variations

2017 ◽  
Vol 27 (10) ◽  
pp. 1569-1588 ◽  
Author(s):  
Shun-Peng Zhu ◽  
Qiang Liu ◽  
Qiang Lei ◽  
Qingyuan Wang
Keyword(s):  
High Pressure ◽  
Fatigue Life ◽  
Life Prediction ◽  
Reliability Assessment ◽  
Fatigue Life Prediction ◽  
Load Spectrum ◽  
High Pressure Turbine ◽  
Random Load ◽  
Load Variations ◽  
Turbine Disc

In the present work, a probabilistic framework for fatigue life prediction and reliability assessment of an engine high pressure turbine disc is proposed to incorporate the effects of load variations and mean stress, which provides a reference for engine structural design under a given target failure probability. Within this framework, a new probabilistic fatigue damage accumulation model under random loadings is elaborated based on a ductility exhaustion model, and probabilistic [Formula: see text] curves for the high pressure turbine disc under different flight missions are derived based on experimental data of turbine disc alloy GH4169. The influence of random load variations on fatigue reliability of the high pressure turbine disc has been investigated and quantified by combining the engine load spectrum with finite element analysis.

A Modified Cumulative Damage Model for Fatigue Life Prediction under Variable Amplitude Loadings

2016 ◽  
Vol 853 ◽  
pp. 62-66 ◽  
Author(s):  
Peng Yue ◽  
Qiang Lei ◽  
Cheng Lin Zhang ◽  
Shun Peng Zhu ◽  
Hong Zhong Huang
Keyword(s):  
Fatigue Damage ◽  
Life Prediction ◽  
Damage Accumulation ◽  
Damage Model ◽  
Cumulative Damage ◽  
Mean Stress ◽  
Stress Model ◽  
Proposed Model ◽  
Fatigue Damage Accumulation ◽  
Cumulative Damage Model

To evaluate the fatigue damage accumulation and predict the residual life of components at different stress levels, this paper proposed a modified cumulative damage model based on the strain energy density parameter. Noting that mean stress and load interaction under uniaxial fatigue loading exhibit significant effects on fatigue damage accumulation and life prediction. According to this, a new model based on damaged stress model which considers the effects of mean stress and load interaction was presented in this paper. The proposed model was verified by using four experimental data sets of aluminium alloys and steels. The experimental results are compared with those of the Miner’s rule, damaged stress model (DSM) and damaged energy model (DEM). Results show that the proposed model agrees better with the experimental observations than others.

Fatigue Life Prediction under Variable Loading Based a Non-Linear Energy Model

2016 ◽  
Vol 22 ◽  
pp. 14-21
Author(s):  
Abdelkader Djebli ◽  
Mostefa Bendouba ◽  
Aid Abdelkarim
Keyword(s):  
Fatigue Life ◽  
Aluminium Alloy ◽  
Fatigue Damage ◽  
Damage Model ◽  
Experimental Results ◽  
Random Loading ◽  
Random Load ◽  
Complex Load ◽  
Proposed Model ◽  
Fatigue Damage Accumulation

A method of fatigue damage accumulation based upon application of energy parameters of the fatigue process is proposed in the paper. Using this model is simple, it has no parameter to be determined, it requires only the knowledge of the curve W–N (W: strain energy density N: number of cycles at failure) determined from the experimental Wöhler curve. To examine the performance of nonlinear models proposed in the estimation of fatigue damage and fatigue life of components under random loading, a batch of specimens made of 6082 T6 aluminium alloy has been studied and some of the results are reported in the present paper. The paper describes an algorithm and suggests a fatigue cumulative damage model, especially when random loading is considered. This work contains the results of uni-axial random load fatigue tests with different mean and amplitude values performed on 6082 T6 aluminium alloy specimens. The proposed model has been formulated to take into account the damage evolution at different load levels and it allows the effect of the loading sequence to be included by means of a recurrence formula derived for multilevel loading, considering complex load sequences. It is concluded that a ‘damaged stress interaction damage rule’ proposed here allows a better fatigue damage prediction than the widely used Palmgren–Miner rule, and a formula derived in random fatigue could be used to predict the fatigue damage and fatigue lifetime very easily. The results obtained by the model are compared with the experimental results and those calculated by the most fatigue damage model used in fatigue (Miner’s model). The comparison shows that the proposed model, presents a good estimation of the experimental results. Moreover, the error is minimized in comparison to the Miner’s model.

Development and Validation of an S-N Based Two Phase Bending Fatigue Life Prediction Model

2003 ◽  
Vol 125 (3) ◽  
pp. 540-544 ◽  
Author(s):  
Avinash Singh
Keyword(s):  
Fatigue Life ◽  
Life Prediction ◽  
Damage Model ◽  
Cumulative Damage ◽  
Fatigue Life Prediction ◽  
Two Phase ◽  
Initiation Phase ◽  
Two Phases ◽  
Life Predictions ◽  
Development And Validation

The stress-life S-N method along with the Palmgren-Miner cumulative damage theory is the simplest and the most commonly used fatigue life prediction technique. Its main advantage is that the material properties needed are easy to collect and life calculation is simple. However under many variable amplitude loading conditions, life predictions have been found to be unreliable. Various modifications have been proposed to the Palmgren-Miner theory, but they have not lead to more reliable life predictions. In this paper, a two-stage cumulative damage model will be developed and validated. This model divides fatigue life into two phases—a crack initiation phase and a crack propagation phase. It will be shown that the proposed method results in greatly improved life prediction capabilities. Also, the proposed method retains the simplicity of the S-N based approach in that the material data is still relatively simple to generate and the calculations are straightforward.

scholarly journals Multiaxial high-cycle fatigue modelling for random loading

2019 ◽  
Vol 300 ◽  
pp. 12005
Author(s):  
Haoyang Wei ◽  
Jie Chen ◽  
Patricio Carrion ◽  
Anahita Imanian ◽  
Nima Shamsaei ◽  
...  
Keyword(s):  
Fatigue Life ◽  
Normal Stress ◽  
Life Prediction ◽  
Equivalent Stress ◽  
Multiaxial Fatigue ◽  
Fatigue Life Prediction ◽  
Load Spectrum ◽  
Critical Plane ◽  
Random Loading ◽  
Random Load

In this paper, a multiaxial fatigue life prediction model is proposed under general multiaxial random loadings. First, a brief review for existing multiaxial fatigue models is given and special focus is on the LiuMahadevan critical plane concept, which can be applied to both brittle and ductile materials. Next, new model development based on the Liu-Mahadevan critical plane concept for random loading is presented. The key concept is to use two-steps to identify the critical plane: identify the maximum damage plane due to normal stress and calculate the critical plane orientation with respect to the maximum damage plane due to normal stress. Multiaxial rain-flow cycle counting method with mean stress correction is used to estimate the damage on the critical plane. Equivalent stress transformation is proposed to convert the multiaxial random load spectrum to an equivalent constant amplitude spectrum. The equivalent stress is used for fatigue life prediction. Following this, experimental design and testing is performed for Al 7075-T6 under various different random uniaxial and multiaxial spectrums. The developed model is validated with both literature and in-house testing data. Very good agreement is observed for the investigated material. Finally, conclusion and future work is given based on the proposed study.

Fatigue Life Prediction of Gear Transmission Based on ANSYS

2014 ◽  
Vol 1055 ◽  
pp. 161-164
Author(s):  
Tao Wang ◽  
Wei Zhong Zhang ◽  
Chen Xie ◽  
Deng Xia Zhang ◽  
Yan Ru
Keyword(s):  
Fatigue Life ◽  
Life Prediction ◽  
Reliable Data ◽  
Cumulative Damage ◽  
Gear Transmission ◽  
Fatigue Life Prediction ◽  
Nominal Stress ◽  
Bending Fatigue ◽  
Unmanned System ◽  
Damage Theory

With the study subject of the gear transmission in an unmanned system, several common methods of fatigue life prediction are analyzed. According to the actual running state, S-N nominal stress method is used to predict the fatigue life of the gears. Based on the S-N data of the gear material and the linear cumulative damage theory, ANSYS is used to estimate the bending fatigue life of the gears, so as to obtain the fatigue life loss coefficient of the gears. It provides a reliable data reference of the design, use and maintenance of the gear transmission in unmanned system.

Sign in / Sign up

Export Citation Format

Share Document