Influence of the Thickness and Frequency in the Infrared Hybrid Method in Consideration of Heat Conduction

2007 ◽  
Vol 353-358 ◽  
pp. 3092-3095
Author(s):  
Kenji Machida ◽  
Shohei Miyagawa
Keyword(s):  
Stress Intensity Factor ◽  
Heat Conduction ◽  
Hybrid Method ◽  
Inverse Analysis ◽  
Cyclic Load ◽  
Measuring Method ◽  
Hybrid Analysis ◽  
Element Analysis ◽  
Stress Components ◽  
Stress Measuring

Recently, the influence of heat conduction has been considered to be a big problem. Then, the influence of heat conduction was investigated by the experiment which changed the material, thickness of the specimen and frequency of a cyclic load. Then, the infrared hybrid method was developed to separate individual stress components. However, it has the influence by heat conduction in the infrared stress measuring method. Therefore, an error will arise in the infrared hybrid analysis. Then, the system which corrects the error by the inverse analysis was developed. Thereby, the accuracy of the stress intensity factor was able to be raised. Furthermore, the accuracy of hybrid method considering to heat conduction was discussed in comparison with the 3-D finite-element analysis and 2-D hybrid method.

Influence of the Thickness of the Specimen in the Infrared Hybrid Method in Consideration of Heat Conduction

2006 ◽  
Vol 321-323 ◽  
pp. 841-844 ◽  
Author(s):  
Kenji Machida ◽  
Shohei Miyagawa
Keyword(s):  
Finite Element Analysis ◽  
Stress Intensity Factor ◽  
Heat Conduction ◽  
Hybrid Method ◽  
Inverse Analysis ◽  
Measuring Method ◽  
Hybrid Analysis ◽  
Element Analysis ◽  
Stress Components ◽  
Stress Measuring

The thickness dependency of the temperature image obtained by an infrared thermography was investigated using specimens with three kinds of materials and four kinds of the thickness of the specimen. Then, the infrared hybrid method was developed to separate individual stress components. However, it had the influence by heat conduction in the infrared stress measuring method. Therefore, an error will occur in the infrared hybrid analysis. Then, the system which corrected the error by the inverse analysis was developed. Thereby, the accuracy of the stress intensity factor was able to be raised. Furthermore, the accuracy of hybrid method considering to heat conduction was discussed in comparison with the 3-D finite-element analysis and 2-D hybrid method.

Effect of the Frequency of the Cyclic Load to the Inverse Analyses of the Heat Conduction in Infrared Thermography

2006 ◽  
Vol 326-328 ◽  
pp. 1137-1140 ◽  
Author(s):  
Kenji Machida ◽  
Shohei Miyagawa
Keyword(s):  
Heat Conduction ◽  
Infrared Thermography ◽  
Hybrid Method ◽  
Inverse Analysis ◽  
Measurement Method ◽  
Cyclic Load ◽  
Stress Measurement ◽  
Hybrid Analysis ◽  
Element Analysis ◽  
Stress Components

Influence of the frequency to the temperature image obtained by an infrared thermography was investigated using specimens of three kinds of materials at four kinds of frequencies of the cyclic load. Then, the infrared hybrid method was developed to separate individual stress components. However, the influence of heat conduction is inevitable in the infrared stress measurement method. Therefore, an error arises in the infrared hybrid analysis. Then, the system which corrects the error by the inverse analysis was developed. Thereby, the accuracy of the stress intensity factor was able to be raised. Furthermore, the accuracy of hybrid method considering to heat conduction was discussed in comparison with the 3-D finite element analysis and 2-D hybrid method.

Influence of the Thickness and Frequency in the Infrared Hybrid Method in Consideration of Heat Conduction

2007 ◽  
Vol 345-346 ◽  
pp. 1287-1290
Author(s):  
Kenji Machida ◽  
Koichi Hayafune ◽  
Shohei Miyagawa
Keyword(s):  
Heat Conduction ◽  
Hybrid Method ◽  
Inverse Analysis ◽  
Measurement Method ◽  
Stress Measurement ◽  
Hybrid Analysis ◽  
Element Analysis ◽  
Stress Components ◽  
Metal Materials ◽  
Conduction Error

The thickness dependency of the temperature image obtained by an infrared thermography was investigated using specimens with three kinds of metal materials of different heat conduction and four kinds of thickness of the specimens. Then, the infrared hybrid method was developed to separate each stress components. However, it contains the influence of heat conduction in the infrared stress measurement method. Therefore, heat conduction error will arise in the infrared hybrid analysis. Then, the new system which corrects the error by an heat conduction inverse analysis was developed. Thereby, the accuracy of the stress intensity factor was able to be raised using heat conduction inverse analysis. Furthermore, the accuracy of hybrid method taking heat conduction into consideration was discussed in comparison with 3-D finite-element analysis and the 2-D infrared hybrid method.

Stress Intensity Factor for Repaired Circumferential Cracks in Pipe With Bonded Composite Wrap

2014 ◽  
Vol 136 (4) ◽  
Author(s):  
F. Benyahia ◽  
A. Albedah ◽  
B. Bachir Bouiadjra
Keyword(s):  
Stress Intensity Factor ◽  
Stress Intensity ◽  
Intensity Factor ◽  
Fracture Criterion ◽  
Three Dimensional ◽  
Element Analysis ◽  
Composite Systems ◽  
Bonded Composite ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element

The use of composite systems as a repair methodology in the pipeline industry has grown in recent years. In this study, the analysis of the behavior of circumferential through cracks in repaired pipe with bonded composite wrap subjected to internal pressure is performed using three-dimensional finite element analysis. The fracture criterion used in the analysis is the stress intensity factor (SIF). The obtained results show that the bonded composite repair reduces significantly the stress intensity factor at the tip of repaired cracks in the steel pipe, which can improve the residual lifespan of the pipe.

Influence of the Material and Thickness of the Specimen on an Infrared Stress Image

2004 ◽  
Vol 261-263 ◽  
pp. 1641-1646
Author(s):  
Kenji Machida ◽  
Mamtimin Gheni
Keyword(s):  
Thermal Conductivity ◽  
Hybrid Method ◽  
Thermal Conduction ◽  
Crack Problem ◽  
High Stress ◽  
High Accuracy ◽  
Problem Analysis ◽  
Principal Stresses ◽  
Distribution Form ◽  
Stress Components

The thickness dependency of the temperature image obtained by an infrared thermography was investigated using specimens with three kinds of materials and four kinds of the thickness of the specimen. Only the sum of the principal stresses which is the first invariant of stress tensor is measured, and it is impossible to measure individual stress components directly. Then, the infrared hybrid method was developed to separate individual stress components. Although the form of the contour line of low stress side differs greatly, the distribution form of high stress side was considerably alike. The stress intensity factor of material with low thermal conductivity can be estimated with high accuracy by the infrared hybrid method. On the crack problem, it was elucidated that the influence of thermal conduction is large and an inverse problem analysis is required.

Parameter identification of concrete dams using swarm intelligence algorithm

2017 ◽  
Vol 34 (7) ◽  
pp. 2358-2378 ◽  
Author(s):  
Siqi Dou ◽  
Junjie Li ◽  
Fei Kang
Keyword(s):  
Parameter Identification ◽  
Swarm Intelligence ◽  
Inverse Analysis ◽  
Arch Dam ◽  
Hydraulic Structures ◽  
Concrete Dams ◽  
Concrete Gravity Dam ◽  
Element Analysis ◽  
Content Type ◽  
Fireworks Algorithm

Purpose Parameter identification is an important issue in structural health monitoring and damage identification for concrete dams. The purpose of this paper is to introduce a novel adaptive fireworks algorithm (AFWA) into inverse analysis of parameter identification. Design/methodology/approach Swarm intelligence algorithms and finite element analysis are integrated to identify parameters of hydraulic structures. Three swarm intelligence algorithms: AFWA, standard particle swarm optimization (SPSO) and artificial bee colony algorithm (ABC) are adopted to make a comparative study. These algorithms are introduced briefly and then tested by four standard benchmark functions. Inverse analysis methods based on AFWA, SPSO and ABC are adopted to identify Young’s modulus of a concrete gravity dam and a concrete arch dam. Findings Numerical results show that swarm intelligence algorithms are powerful tools for parameter identification of concrete structures. The proposed AFWA-based inverse analysis algorithm for concrete dams is promising in terms of accuracy and efficiency. Originality/value Fireworks algorithm is applied for inverse analysis of hydraulic structures for the first time, and the problem of parameter selection in AFWA is studied.

The Experimental Study of Diffraction Angle of Aluminum Alloy 3003

2012 ◽  
Vol 625 ◽  
pp. 291-296
Author(s):  
Neng Quan Duan ◽  
Jian Liang Ren ◽  
Rui Qiang Pang
Keyword(s):  
Residual Stress ◽  
Aluminum Alloy ◽  
Stress Measurement ◽  
Electrical Measuring ◽  
Diffraction Method ◽  
Measuring Method ◽  
X Ray ◽  
Equal Strength ◽  
Diffraction Angle ◽  
Stress Measuring

The most suitable diffraction angle of aluminum alloy 3003 used for stress measuring is aimed to be determined in this paper. The experiment makes a stress measurement of a loading aluminum alloy 3003 equal strength beam with the traditional electrical measuring method and the X-ray stress measurement. With the electrical measuring method as reference, the research study the measured values that acquired from the X-ray diffraction method when the diffraction angle are 142° and 156°, and then compare them with that acquired from electrical measuring method. The measurement results demonstrate that the diffraction angle at 156 ° is better than at 142 ° based on the assessment standards of the liner slope and the distribution of data. Thus the optimum diffraction angle for X-ray to measure the macroscopic stress of aluminum alloy 3003 is 156 °. In this paper，the stress caused by the load on the equal strength beam is assumed to be "residual stress" and thus the conclusion has reference values for the standardization of residual stress measurement of aluminum alloy by XRD and has theoretical guiding significance in the production practices.

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