Study on Pulsed Eddy Current Nondestructive Testing Technology for Pipeline Corrosion Defects Based on Finite Element Method

2011 ◽  
Vol 120 ◽  
pp. 36-41 ◽  
Author(s):  
Han Wu Liu ◽  
Shan Ping Zhan ◽  
Yun Hui Du ◽  
Peng Zhang

According to the principle and the type of the oil pipeline corrosion, we use the square wave of wide spectrum, strong signal transmission capability and a certain duty ratio as the excitation source of the pulsed eddy current. The finite element analysis software ANSYS is used to establish a three-dimensional finite element model of the pipeline corrosion defects by applying the boundary conditions of square wave excitation to simulate the distributions of current and induced magnetic field in the pipeline under various defect volumes. It can solve the induced voltage variation with time on detection coil, and can accomplish the finite element analysis and the nondestructive testing about the pipeline internal corrosion defects with the insulation layer and the protection layer. The results of the study show: When there is no corrosion defect in the pipeline, the electric current in the pipeline is basically even distribution. The magnetic field is distributed for the symmetrical vortex shape from head to foot, and it has not obviously gather phenomenon. When there are some corrosion defects in the pipeline, the electric current forms partial symmetrical vortex shape in both sides of the corrosion defect, and it is obviously assembled in the defect place. The simulation results of the different size defects show that the maximum magnetic field strength and the maximum current value increase with the defect depth increasing, while the output voltage decreases with the defect depth increasing. By extracting the induced voltage signals on the detection coil in a certain excitation condition, the quantitative detection of the pipeline corrosion defects can be achieved.

2012 ◽  
Vol 215-216 ◽  
pp. 1154-1157
Author(s):  
Han Wu Liu ◽  
Rui Hua Dong ◽  
Han Xun Lv

Finite element analysis software ANSYS is used to establish a three-dimensional finite element model of the pipeline corrosion defects by applying the boundary conditions of square wave excitation to simulate the distributions of current and induced magnetic field in the pipeline under various defect volumes. The results of the study show: When there is no corrosion defect in the pipeline, the electric current in the pipeline is basically even distribution. The magnetic field is distributed for the symmetrical vortex shape from head to foot, and it has not obviously gather phenomenon. When there are some corrosion defects in the pipeline, the electric current forms partial symmetrical vortex shape in both sides of the corrosion defect, and it is obviously assembled in the defect place. The simulation results of the different size defects show that the maximum magnetic field strength and the maximum current value increase with the defect depth increasing, while the output voltage decreases with the defect depth increasing. For the analysis of the stress distributions of the pipeline corrosion defect with certain size under different pressures, it was found that the maximum stress is 596 MPa when the bearing limit work pressure of the pipeline is 7 MPa, which is smaller than the yield strength with ensuring the safely running of the pipelines with defects.


2012 ◽  
Vol 605-607 ◽  
pp. 1427-1430 ◽  
Author(s):  
Fan Zhang ◽  
Zhi Xin Ma ◽  
Shang Gao

Based on the structure and working principle of our giant magnetostrictive actuator (GMA), the properties of the driving magnetic field were researched. A 3-D nonlinear magnetic field model of the GMA was established with the finite element analysis method, and the magnetic field distribution of the GMA was obtained with the software ANSYS. Then the 3-D model helped us to find the effects about the distribution of magnetic field of the GMA from the structure. The 3-D magnetic field finite element analysis model can give us a new tool of GMA design and analysis.


Author(s):  
Elaine Sung ◽  
Anil Erol ◽  
Mary Frecker ◽  
Paris von Lockette

Magneto-active elastomers (MAEs) are polymers with magnetic particles that are capable of aligning with an external magnetic field; this self-alignment ability is one reason why MAEs can be used as actuators for folding or bending in origami engineering. The focus of this paper is on experimental characterization and finite element modeling of an MAE folding accordion structure. The goal is to understand the relationships among the applied magnetic field, displacement of the structure during actuation, and the resultant reaction force generated. This relationship is important for applications where force generation caused by the actuation of MAE structures is required. Data show that force increases with increasing magnetic field, and the work done by the structure can also be calculated by integrating the force. Good agreement between the finite element analysis and experimental data is shown. Future methods for improving experimentation and modeling are discussed based on the results.


2011 ◽  
Vol 216 ◽  
pp. 528-532 ◽  
Author(s):  
Hai Lin Tan ◽  
Xiao Bin Jiang

Use multiphysics module in finite element analysis software ANSYS to analyse Magnetorheological elastomer isolator of Static magnetic field and modal. Thus making a comprehensive evaluation to The design of the isolator whether it can meet the performance requirements and stability in the actual work.


1985 ◽  
Vol 13 (3) ◽  
pp. 127-146 ◽  
Author(s):  
R. Prabhakaran

Abstract The finite element method, which is a numerical discretization technique for obtaining approximate solutions to complex physical problems, is accepted in many industries as the primary tool for structural analysis. Computer graphics is an essential ingredient of the finite element analysis process. The use of interactive graphics techniques for analysis of tires is discussed in this presentation. The features and capabilities of the program used for pre- and post-processing for finite element analysis at GenCorp are included.


2007 ◽  
Vol 35 (3) ◽  
pp. 226-238 ◽  
Author(s):  
K. M. Jeong ◽  
K. W. Kim ◽  
H. G. Beom ◽  
J. U. Park

Abstract The effects of variations in stiffness and geometry on the nonuniformity of tires are investigated by using the finite element analysis. In order to evaluate tire uniformity, a three-dimensional finite element model of the tire with imperfections is developed. This paper considers how imperfections, such as variations in stiffness or geometry and run-out, contribute to detrimental effects on tire nonuniformity. It is found that the radial force variation of a tire with imperfections depends strongly on the geometrical variations of the tire.


2018 ◽  
Vol 55 (4) ◽  
pp. 666-675
Author(s):  
Mihaela Tanase ◽  
Dan Florin Nitoi ◽  
Marina Melescanu Imre ◽  
Dorin Ionescu ◽  
Laura Raducu ◽  
...  

The purpose of this study was to determinate , using the Finite Element Analysis Method, the mechanical stress in a solid body , temporary molar restored with the self-curing GC material. The originality of our study consisted in using an accurate structural model and applying a concentrated force and a uniformly distributed pressure. Molar structure was meshed in a Solid Type 45 and the output data were obtained using the ANSYS software. The practical predictions can be made about the behavior of different restorations materials.


2013 ◽  
Vol 83 (7) ◽  
pp. 1087-1096 ◽  
Author(s):  
A. Ranjbaran ◽  
H. Rousta ◽  
M. O. Ranjbaran ◽  
M. A. Ranjbaran ◽  
M. Hashemi ◽  
...  

2012 ◽  
Vol 24 (3) ◽  
pp. 326-333 ◽  
Author(s):  
Yu-Chi Chen ◽  
Wen-Ching Ko ◽  
Han-Lung Chen ◽  
Hsu-Ching Liao ◽  
Wen-Jong Wu ◽  
...  

We propose a model to give us a method to investigate the characteristic three-dimensional directivity in an arbitrarily configured flexible electret-based loudspeaker. In recent years, novel electret loudspeakers have attracted much interest due to their being lightweight, paper thin, and possessing excellent mid- to high-frequency responses. Increasing or decreasing the directivity of an electret loudspeaker makes it excellent for adoption to many applications, especially for directing sound to a particular area or specific audio location. Herein, we detail a novel electret loudspeaker that possesses various directivities and is based on various structures of spacers instead of having to use multichannel amplifiers and a complicated digital control system. In order to study the directivity of an electret loudspeaker based on an array structure which can be adopted for various applications, the horizontal and vertical polar directivity characteristics as a function of frequency were simulated by a finite-element analysis model. To validate the finite-element analysis model, the beam pattern of the electret loudspeaker was measured in an anechoic room. Both the simulated and experimental results are detailed in this article to validate the various assertions related to the directivity of electret cell-based smart speakers.


Sign in / Sign up

Export Citation Format

Share Document