Three-dimensional coupled thermo-mechanical analysis for fatigue failure of a heavy vehicle brake disk: Simulation of braking and cooling phases

In this paper, transient coupled thermo-mechanical finite element analysis of a three-dimensional model of braking pairs (brake disk and brake pads) is accomplished in order to estimate temperatures and stresses in brake disk during a braking cycle, including braking and cooling phases, and calculate fatigue life. A nonuniform distribution of temperatures is revealed on the surface of the brake disk, gradually generating surface hot spots and hot bands with temperatures up to 800 °C that lead to an uneven distribution of thermal stresses on the frictional surfaces. According to the simulations, variations in the circumferential stress, which is mainly responsible for the cracking of the brake disk, can reach up to 400 MPa in the hot spot areas, depending on the braking configurations. The numerical results are also used to estimate the fatigue life of brake disk using the Smith–Watson–Topper model. The numerical model demonstrates a high accuracy of fatigue life estimation when evaluated by prior experimental studies, signifying the effects of hot spots in reducing the service life of brake disk. Results of the fatigue life estimation show superiority to the analytical method both in the accuracy of calculation and detection of the failure location.

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Transient Stress Analysis and Fatigue Life Estimation of Turbine Blades

Journal of Vibration and Acoustics ◽

10.1115/1.1804996 ◽

2004 ◽

Vol 126 (4) ◽

pp. 485-495 ◽

Cited By ~ 5

Author(s):

Deepak Dhar ◽

A. M. Sharan ◽

J. S. Rao

Keyword(s):

Fatigue Life ◽

Thermal Stresses ◽

Turbine Blades ◽

Three Dimensional ◽

Element Analysis ◽

Life Estimation ◽

Start Up ◽

Fatigue Life Estimation ◽

Transfer Equations ◽

Number Of Cycles

This paper is concerned with life estimation of a turbine blade taking into account the combined effects of centrifugal stresses, vibratory stresses and thermal stresses. The stresses are determined by accounting for the rotor acceleration. The blades are subjected to aerodynamic excitation force obtained from thin cambered aerofoil theory under incompressible flow. The thermo-elastic forces are obtained from the three-dimensional non-linear heat transfer equations using the finite element analysis. The fatigue life is estimated using two well known theories, from the number of cycles in various blocks during start-up and shut-down periods of the turbine operation when the stresses peak.

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Transient Stress Analysis and High Cycle Fatigue Life Estimation of a Gas Turbine Shrouded HP Compressor Blade

ASME 2016 Power Conference ◽

10.1115/power2016-59336 ◽

2016 ◽

Author(s):

Vinayaka Nagarajaiah ◽

Nilotpal Banerjee ◽

B. S. Ajay Kumar ◽

Kumar K. Gowda ◽

Tulsidas Dalappa

Keyword(s):

Fatigue Life ◽

Gas Turbine ◽

Thermal Stresses ◽

High Cycle Fatigue ◽

Structural Integrity ◽

Resonance Condition ◽

Cycle Fatigue ◽

Element Analysis ◽

Life Estimation ◽

Fatigue Life Estimation

This work is focused on developing a technique to assess high cycle fatigue of shrouded HP compressor blades subjected to thermo-mechanical loads like centrifugal stresses, vibratory stresses and thermal stresses in a gas turbine rotor. In practice, the blades are also subjected to resonance condition during steady or transient conditions of operation when passing through critical speeds. Hence, shrouds are added initially at 3/4 length along blade height which helps in reducing vibration amplitude by providing suitable stiffness to the blade and hence better structural integrity. Industrial best practice like Campbell diagram is used for the above purpose. Two approaches employed here for fatigue analysis are linear Finite element analysis (FEA) and Elasto-Plastic FEA. Fictive elastic results are recalculated using Neuber’s Rule. Strain amplitude approach is followed and Coffin-Manson Equation is used to determine the number of start-up and shut-down cycles. Design and analysis is performed using ANSYS 14.5 tool for reliable fatigue life estimation and to predict catastrophic failure due to High Cycle Fatigue.

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Fatigue Life Estimation of the Tail Boom and Vertical Stabilizer of MI-24 Helicopter

Fatigue of Aircraft Structures ◽

10.2478/v10164-010-0028-4 ◽

2010 ◽

Vol 2010 (2) ◽

Author(s):

Piotr Reymer ◽

Andrzej Leski

Keyword(s):

Fatigue Life ◽

Life Estimation ◽

Fatigue Life Estimation

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Load Spectrum Compiling and Fatigue Life Estimation of the Automobile Wheel Hub

Recent Patents on Mechanical Engineering ◽

10.2174/2212797613999201231200939 ◽

2020 ◽

Vol 13 ◽

Author(s):

Xintian Liu ◽

Yang Qu ◽

Xiaobing Yang ◽

Yongfeng Shen

Keyword(s):

Fatigue Life ◽

High Speed ◽

Two Dimensional ◽

Load Spectrum ◽

One Dimensional ◽

Life Estimation ◽

Load Spectra ◽

Fatigue Life Estimation ◽

Program Load Spectrum ◽

Program Load

Background:: In the process of high-speed driving, the wheel hub is constantly subjected to the impact load from the ground. Therefore, it is important to estimate the fatigue life of the hub in the design and production process. Objective:: This paper introduces a method to study the fatigue life of car hub based on the road load collected from test site. Methods:: Based on interval analysis, the distribution characteristics of load spectrum are analyzed. The fatigue life estimation of one - dimensional and two - dimensional load spectra is compared by compiling load spectra. Results:: According to the S-N curve cluster and the one-dimensional program load spectrum, the estimated range fatigue life of the hub is 397,100 km to 529,700 km. For unsymmetrical cyclic loading, each level means and amplitude of load were obtained through the Goodman fatigue empirical formula, and then according to S-N curve clusters in the upper and lower curves and two-dimensional program load spectrum, estimates the fatigue life of wheel hub of the interval is 329900 km to 435200 km, than one-dimensional load spectrum fatigue life was reduced by 16.9% - 17.8%. Conclusion:: This paper lays a foundation for the prediction of fatigue life and the bench test of fatigue durability of auto parts subjected to complex and variable random loads. At the same time, the research method can also be used to estimate the fatigue life of other bearing parts or high-speed moving parts and assemblies.

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Study on the Fatigue Life Estimation of an Airframe Fuselage Window Cutout Panel

International Journal for Research in Applied Science and Engineering Technology ◽

10.22214/ijraset.2018.5408 ◽

2018 ◽

Vol 6 (5) ◽

pp. 2501-2510

Author(s):

C Vivek Raj

Keyword(s):

Fatigue Life ◽

Life Estimation ◽

Fatigue Life Estimation

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A path-dependent multiaxial fatigue life estimation criterion for metals under various loading conditions

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2021.106300 ◽

2021 ◽

pp. 106300

Author(s):

Jing Li ◽

Yuan-ying Qiu

Keyword(s):

Fatigue Life ◽

Multiaxial Fatigue ◽

Loading Conditions ◽

Life Estimation ◽

Fatigue Life Estimation ◽

Path Dependent

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Notch fatigue life estimation of Ti-6Al-4V

Engineering Failure Analysis ◽

10.1016/j.engfailanal.2020.105098 ◽

2021 ◽

Vol 120 ◽

pp. 105098

Author(s):

Camilla Ronchei ◽

Sabrina Vantadori

Keyword(s):

Fatigue Life ◽

Life Estimation ◽

Fatigue Life Estimation

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An Investigation of Cyclic Transient Behavior and Implications on Fatigue Life Estimates

Journal of Engineering Materials and Technology ◽

10.1115/1.2805989 ◽

1997 ◽

Vol 119 (2) ◽

pp. 161-170 ◽

Cited By ~ 35

Author(s):

Yanyao Jiang ◽

Peter Kurath

Keyword(s):

Stainless Steel ◽

Fatigue Life ◽

Cyclic Hardening ◽

Transient Behavior ◽

Fatigue Tests ◽

304 Stainless Steel ◽

Deformation History ◽

Life Estimation ◽

Fatigue Life Estimation ◽

Track Deformation

Current research focuses on proportional cyclic hardening and non-Massing behaviors. The interaction of these two hardenings can result in the traditionally observed overall softening, hardening or mixed behavior exhibited for fully reversed strain controlled fatigue tests. Proportional experiments were conducted with five materials, 304 stainless steel, normalized 1070 and 1045 steels, and 7075-T6 and 6061-T6 aluminum alloys. All the materials display similar trends, but the 304 stainless steel shows the most pronounced transient behavior and will be discussed in detail. Existing algorithms for this behavior are evaluated in light of the recent experiments, and refinements to the Armstrong-Frederick class of incremental plasticity models are proposed. Modifications implemented are more extensive than the traditional variation of yield stress, and a traditional strain based memory surface is utilized to track deformation history. Implications of the deformation characteristics with regard to fatigue life estimation, especially variable amplitude loading, will be examined. The high-low step loading is utilized to illustrate the effect of transient deformation on fatigue life estimation procedures, and their relationship to the observed and modeled deformation.

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