A Rapid Fatigue Analysis Method of Aluminum Honeycomb Structure with Defects Based on Static Test and Numerical Simulation

This study investigated the wind turbine blade root bolt static strength using the full scale static test, selected the root bolts of 1/4 bridge strain gauge using the finite element analysis method and the dynamic and static strain instrument. The data of the stress loading combined tension and bending bolt were obtained.

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Hybrid Fatigue Analysis Method for Railway Carbody Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.44-46.733 ◽

2008 ◽

Vol 44-46 ◽

pp. 733-738 ◽

Cited By ~ 1

Author(s):

Bing Rong Miao ◽

Wei Hua Zhang ◽

Shou Ne Xiao ◽

Ding Chang Jin ◽

Yong Xiang Zhao

Keyword(s):

Fatigue Life ◽

Fatigue Damage ◽

Hybrid Method ◽

Dynamic Stress ◽

Stress Test ◽

Fatigue Analysis ◽

Railway Vehicle ◽

Analysis Method ◽

Structure Dynamic ◽

Multi Body

Railway vehicle structure fatigue life consumption monitoring can be used to determine fatigue damage by directly or indirectly monitoring the loads placed on critical vehicle components susceptible to failure from fatigue damage. The sample locomotive carbody structure was used for this study. Firstly, the hybrid fatigue analysis method was used with Multi-Body System (MBS) simulation and Finite Element Method (FEM) for evaluating the carbody structure dynamic stress histories. Secondly, the standard fatigue time domain method was used in fatigue analysis software FE-FATIGUE and MATLAB WAFO (Wave Analysis for Fatigue and Oceanography) tools. And carbody structure fatigue life and fatigue damage were predicted. Finally, and carbody structure dynamic stress experimental data was taken from this locomotive running between Kunming-Weishe for this analysis. The data was used to validate the simulation results based on hybrid method. The analysis results show that the hybrid method prediction error is approximately 30.7%. It also illustrates that the fatigue life and durability of the locomotive can be predicted with this hybrid method. The results of this study can be modified to be representative of the railway vehicle dynamic stress test.

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An Idealization of Wave Scatter Diagram for Spectral Fatigue Analysis

Volume 2: Structures, Safety and Reliability ◽

10.1115/omae2009-79721 ◽

2009 ◽

Author(s):

Min Han Oh ◽

Ki Myung Lee ◽

Young Sik Jang

Keyword(s):

Fatigue Analysis ◽

Scatter Diagram ◽

Analysis Method ◽

Sea State ◽

Environmental Loads ◽

Wave Data ◽

Wave Measurements ◽

Spectral Models ◽

Wave Heights ◽

Significant Wave Heights

A spectral fatigue analysis method is most popularly applied for the detailed design of FPSOs. As the environmental loads at the installation site are directly calculated in the spectral analysis, this method gives the most reliable results although it needs much time-consuming works to fully reflect the environmental loads. As the technology of wave measurements advances, the measured wave data increase. Also their spectral models are very complicated because these include many wave components such as swells and wind seas. Since much time and effort are needed to treat these enormous and complicated wave data for the spectral fatigue analysis, a rational idealization of wave data is definitely required. In this paper, wave scatter diagram at Offshore Nigeria was reviewed and their idealization method was proposed. The influence level of each sea state of the wave scatter diagram was identified considering the fatigue damage levels estimated from the significant wave heights and dominant fatigue load RAOs. The sea states giving small fatigue damages were lumped symmetrically by merging or disregarding while those giving large fatigue damages were kept as original. For the validation of this method, the comparisons of dominant fatigue loads and representative fatigue damages were presented for the idealized wave scatter diagram and the original one. From these comparison works, it was confirmed that the idealized wave scatter diagram gives reliable results with reduced amount of calculation work.

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Design and Fabrication of Novel Electrode-Supported SOFC Having Honeycomb Structure

ASME 2008 6th International Conference on Fuel Cell Science, Engineering and Technology ◽

10.1115/fuelcell2008-65065 ◽

2008 ◽

Author(s):

Toshiaki Yamaguchi ◽

Toshio Suzuki ◽

Yoshinobu Fujishiro ◽

Masanobu Awano ◽

Sota Shimizu

Keyword(s):

Numerical Simulation ◽

Pressure Drop ◽

Cost Reduction ◽

Unit Volume ◽

Honeycomb Structure ◽

Current Collection ◽

Fuel Flow ◽

Space Saving ◽

Channel Surface ◽

Calculation Results

We have developed a novel and highly effective electrode-supported SOFC with honeycomb structure for intermediate temperature operation. Honeycomb supported SOFC is known as one of the most compact SOFCs due to the large electrode area per unit volume, which is attractive with regard to space saving and cost reduction. In this study, we summarized the design of channel shape, size and sequence using numerical simulation and the technologies to realize the designed honeycomb SOFC fabrication. The calculation results showed that the wall thickness and the channel size of the honeycomb had to be less than 0.22 mm and more than 0.3 mm, respectively, for the sufficient net channel surface and the acceptable pressure drop. And a cathode-honeycomb supported SOFC can be the more efficient form with the lower current collection resistance, as compared with the anode-supported type. The actually fabricated honeycomb SOFC exhibited a high volumetric power density above 1 W/cm3 at 650 °C under wet H2 fuel flow.

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Insulated Cable Temperature Calculation and Numerical Simulation

MATEC Web of Conferences ◽

10.1051/matecconf/201817503014 ◽

2018 ◽

Vol 175 ◽

pp. 03014

Author(s):

Xin-jian Li ◽

Jun Yang ◽

Bing-qiang Yan ◽

Xiao Zheng

Keyword(s):

Numerical Simulation ◽

Mathematical Model ◽

Spontaneous Combustion ◽

Practical Significance ◽

Constant Current ◽

Sectional Area ◽

Analysis Method ◽

Insulation Layer ◽

Insulating Layer ◽

Temperature Calculation

A mathematical model of electrified insulated cable was established to calculate temperature of insulating layer. The insulating layer temperature is determined as a function of the current intensity, time, insulation layer thickness, etc. A widely used polyvinyl chloride (PVC) cable with sectional area of 4 mm2 was selected as example and its insulating layer temperature was simulated using ANSYS. The simulation revealed the evolution of insulating layer temperature with time, and also along radius after a certain time when the cable was applied with 40A and 60A constant current respectively. The analysis method has practical significance to prevent electrical fire and can be applied to analyze spontaneous combustion accident of insulated cable.

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A Shortcut Fatigue Analysis Method

Journal of Offshore Mechanics and Arctic Engineering ◽

10.1115/1.2919830 ◽

1990 ◽

Vol 112 (1) ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

H. M. Thompson

Keyword(s):

Fatigue Life ◽

Transfer Function ◽

Fatigue Analysis ◽

Analysis Method ◽

Dynamic Amplification Factor ◽

Single Degree Of Freedom ◽

At Resonance ◽

Order Of Magnitude ◽

Dynamic Amplification ◽

Good Agreement

A shortcut fatigue analysis method is presented which can be used to provide fatigue life estimates during the preliminary design phase of deepwater fixed platforms. For this type of structure, the method is intended to provide order of magnitude fatigue life estimates only. For simpler structures, such as deepwater offshore caissons, the shortcut analysis can provide good agreement with a detailed spectral fatigue analysis. The fundamental assumption of the method is that the dynamic transfer function can be closely approximated by the product of the static transfer function and a single degree of freedom dynamic amplification factor, which has been adjusted to produce a “fit” to the true DAF at resonance. Only one dynamic analysis of the structure needs to be performed, i.e., to determine the true DAF at resonance.

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Effects of Blade Counts and Clocking on the Unsteady Profile Pressure Distribution in an Axial-Radial Combined Compressor

Volume 6C: Turbomachinery ◽

10.1115/gt2013-94251 ◽

2013 ◽

Cited By ~ 2

Author(s):

Ben Zhao ◽

Ce Yang ◽

Liangjun Hu ◽

Dazhong Lao

Keyword(s):

Numerical Simulation ◽

Data Analysis ◽

Pressure Distribution ◽

Pressure Fluctuations ◽

Blade Surface ◽

Analysis Method ◽

Unsteady Pressure ◽

Stator Blade ◽

Multistage Compressor ◽

New Hypothesis

A new hypothesis is presented for the superimposed effects of the blade pressure distribution in a multistage compressor. The effects of the unsteady pressure fluctuations on the blade surface are separated into three groups. The influences of the upstream or downstream rotors can be obtained by numerical simulation for the R/S or S/R configuration; the data produced by all the influences can be obtained from the R/S/R configuration. The effects of the blade counts and clocking on the superimposed effects, acting on the profile pressure distribution, are studied using a special data analysis method that had been previously developed by the authors. The results indicate that the blade counts of the upstream and downstream rotors determine the periods of the unsteady pressure fluctuations on the stator surface. The clocking moving blade rows modulate the relative superimposed phases and interactions between two rotors such that the unsteady pressure fluctuates with different amplitudes on the surface of the stator blade.

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