A Finite Element Model for Elastic and Slip Responses of Fusion Magnets

1980 ◽  
Vol 102 (2) ◽  
pp. 219-225
Author(s):  
T. Y. Chang ◽  
H. Suzuki ◽  
M. Reich
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Bonding Strength ◽  
Element Model ◽  
Type Model ◽  
Shear Stresses ◽  
Homogenization Procedure ◽  
Numerical Examples ◽  
Proposed Model ◽  
Interlayer Slip

A finite element model to simulate the elastic and slip responses of fusion magnets under operating loads is proposed. To represent the elastic actions, a material homogenization procedure based on the existing composite technology was applied to obtain the effective stress strain relations for the heterogeneous, laminated magnets. In addition, a friction-type model was utilized to simulate the interlayer slip of the magnets when the shear stresses reach the bonding strength of the adhesives. Numerical examples are given to demonstrate the applicability of the proposed model.

Reduction of Free-Edge Stress Concentration

1985 ◽  
Vol 52 (4) ◽  
pp. 801-805 ◽  
Author(s):  
P. R. Heyliger ◽  
J. N. Reddy
Keyword(s):  
Finite Element ◽  
Stress Concentration ◽  
Finite Element Model ◽  
Three Dimensional ◽  
Element Model ◽  
Free Edge ◽  
Shear Stresses ◽  
Normal Stresses ◽  
Interlaminar Shear ◽  
Three Dimensional Elasticity

A quasi-three dimensional elasticity formulation and associated finite element model for the stress analysis of symmetric laminates with free-edge cap reinforcement are described. Numerical results are presented to show the effect of the reinforcement on the reduction of free-edge stresses. It is observed that the interlaminar normal stresses are reduced considerably more than the interlaminar shear stresses due to the free-edge reinforcement.

Groove Geometry and Mold Shrinkage Effects on Die Stress in Flip Chip Molded BGAs (FCMBGA)

2013 ◽  
Vol 2013 (DPC) ◽  
pp. 000455-000470
Author(s):  
Bora Baloglu ◽  
Miguel Jimarez ◽  
Ahmer Syed
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Flip Chip ◽  
Element Model ◽  
Shear Stresses ◽  
Back Side ◽  
Molding Process ◽  
Finite Elements Analysis ◽  
Design Guideline ◽  
Structural Support

Exposed die flip chip molded BGA (FCMBGA) packages are preferred for their improved thermal performance and reduced system cost. In this package type, mold compound replaces the traditional capillary underfill and also provides a better stiffening option for the package without the need for additional structural support such as lid and/or stiffening ring. In addition, it allows better utilization of the board real estate as the passive components can be placed closer to the die. Groove or an undercut is the shape of the mold around the exposed die that is formed during the molding process. To ensure a mold-free top surface of the die, a seal (soft insert) that has a larger surface area than the die is being used to cover the die top surface. This larger portion of the seal outlines the groove geometry when it is compressed on top of the die. Seal size can be designed to establish certain groove geometry. Thus, it is important to characterize/understand the effects of the groove geometry as it is a design parameter and can be adjusted to create more robust molded packages. In this study, specific groove width and depth values for various package configurations are investigated using finite elements analysis, FEA. Initially, a detailed finite element model is prepared and warpage simulation is performed. Model correlation to the actual Shadow Moiré is obtained. Then, using the correlated finite element model, die back side stress and shear stresses, where die faces mold compound, are obtained for a thermal cool down simulation from the molding temperature. Mold compound shrinkage is also considered by using an adjusted thermal expansion coefficient value. As a validation study, a test mold chase/tool for varying insert sizes has been designed and, molded packages with different groove geometries and different mold compounds were build. Using the correlation between the test data and the simulation results an order of importance (based on the groove geometry parameters and mold compound's material properties) will be presented which then, can be used as a design guideline to change the groove geometry to produce more robust molded packages.

A Method for Determining the Springing Displacements of Arch Bridges without Technical Data

2011 ◽  
Vol 94-96 ◽  
pp. 375-380
Author(s):  
Xiao Dong Zhang ◽  
Yong Qiang Zhang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Optimization Problem ◽  
Element Model ◽  
Technical Data ◽  
Numerical Examples ◽  
The Difference ◽  
Arch Bridges ◽  
The One ◽  
The Finite Element Model

A method for determining the springing displacements and arch axis of old arch bridges without technical data is presented. By minimizing the difference between the arch axis predicted by the finite element model and the one obtained by assumed arch equation, the optimization problem is formulated and solved. Two numerical examples are given and the results are discussed.

scholarly journals Finite Element Model Optimization Using Diagonal Mass Matrix

1997 ◽  
Vol 4 (3) ◽  
pp. 163-168
Author(s):  
B.P. Wang ◽  
F.H. Chu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Mass Matrix ◽  
Element Model ◽  
Model Optimization ◽  
Simple Method ◽  
Numerical Examples ◽  
Modal Data

By adjusting the analytic mass matrix or stiffness parameters, the correlation between measured and computed modal data can be improved. This article proposes a simple method for model optimization. Numerical examples will be included to illustrate the proposed approach.

scholarly journals Temperature Modeling of AISI 1045 Steel during Surface Hardening Processes

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1815 ◽  
Author(s):  
Tsung-Pin Hung ◽  
Hao-En Shi ◽  
Jao-Hwa Kuang
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Surface Hardening ◽  
Treatment Process ◽  
Scanning Speed ◽  
Element Model ◽  
Laser Surface ◽  
Single Track ◽  
Proposed Model ◽  
Aisi 1045

A Coupled thermo-mechanical finite element model was employed to simulate the possible effects of varying laser scanning parameters on the surface hardening process for AISI 1045 and AISI 4140 steels. We took advantage of the high-power density of laser beams to heat the surface of workpieces quickly to achieve self-quenching effects. The finite element model, along with the temperature-dependent material properties, was applied to characterize the possible quenching and tempering effects during single-track laser surface heat treatment. We verified the accuracy of the proposed model through experiments. The effects of laser surface hardening parameters, such as power variation, scanning speed, and laser spot size, on the surface temperature distribution, hardening width, and hardening depth variations during the single-track surface laser treatment process, were investigated using the proposed model. The analysis results show that laser power and scanning speed are the key parameters that affect the hardening of the material. The numerical results reveal that the proposed finite element model is able to simulate the laser surface heat treatment process and tempering effect of steel.

Deformation of the Pneumatic Tire

1978 ◽  
Vol 6 (4) ◽  
pp. 233-247 ◽  
Author(s):  
H. P. Patel ◽  
C. F. Zorowski
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Material Properties ◽  
Thin Shell ◽  
Element Model ◽  
Shell Of Revolution ◽  
Actual Situation ◽  
Pneumatic Tire ◽  
Proposed Model ◽  
Experimental Values

Abstract A finite element model is presented for analysis of axisymmetric static loadings of a bias ply pneumatic tire. The model can predict deformed shapes and the resulting cord forces in the tire. The tire is considered as a thin shell of revolution with membrane and bending stiffness. Its material properties are assumed to be linearly orthotropic. Large axisymmetric deformations studied with the proposed model gave very close approximations to the actual situation. The predicted cord forces matched the experimental values very closely.

3D bending simulation and mechanical properties of the OLED bending area

Open Physics ◽  
2020 ◽  
Vol 18 (1) ◽  
pp. 397-407
Author(s):  
Liang Ma ◽  
Jinan Gu
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Stress Relaxation ◽  
Finite Element Model ◽  
3D Model ◽  
Simulation Models ◽  
Element Model ◽  
Uniaxial Tensile ◽  
Proposed Model ◽  
Stress Changes

AbstractDue to the poor mechanical properties of traditional simulation models of the organic light-emitting device (OLED) bending area, this article puts forward a finite element model of 3D bending simulation of the OLED bending area. During the model construction, it is necessary to determine the viscoelastic and hyperelastic mechanical properties, respectively. In order to accurately obtain the stress changes of material deformation during the hyperelasticity determination, a uniaxial tensile test and a shear test were used to obtain data and thus to characterize the hyperelastic properties. In order to measure the viscoelasticity, a stress relaxation test was used to draw the stress relaxation curve, so as to characterize the viscoelastic properties. Then, the plane or axisymmetric stress–strain analysis was achieved, and the material parameters of the 3D model of the OLED bending area were obtained. Finally, the 3D model was applied to the 3D bending of the OLED bending area. Combined with the axisymmetric finite element analysis method, the 3D bending simulation finite element model of the OLED bending area was constructed by dividing the finite element mesh. Experimental results show that the mechanical properties of the proposed model are better than those of traditional OLED bending simulation models. Meanwhile, the proposed model has stronger application advantages.

Study of Modeling and Distortion Predicting for Multi-Frame Components

2010 ◽  
Vol 136 ◽  
pp. 221-226
Author(s):  
Jie Chen
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Prediction Method ◽  
Element Model ◽  
Element Simulation ◽  
Proposed Model ◽  
Distortion Analysis ◽  
Simulation Results ◽  
House Building ◽  
The Finite Element Model

In this study, a method called “house-building frame modeling” based on the APDL language is introduced firstly, and the finite element model of the milling distortion analysis is established for a platform structure with 192 frames by the method, and the prediction analysis of the milling distortion under different milling conditions is carried out, by means of 3-D finite element simulation technology. Comparing the simulation results and the measurement ones of the milling distortion, the proposed model is modified; the modeling method and prediction method are proved to be effective.

A Finite Element Model for Composite Beams with Piezoelectric Layers using A Sinus Model

2010 ◽  
Vol 26 (3) ◽  
pp. 335-344 ◽  
Author(s):  
S. B. Beheshti-Aval ◽  
M. Lezgy-Nazargah
Keyword(s):  
Finite Element ◽  
Virtual Work ◽  
Element Model ◽  
Composite Beams ◽  
Shear Stresses ◽  
Sensors And Actuators ◽  
Virtual Work Principle ◽  
Proposed Model ◽  
Piezoelectric Layers ◽  
Transverse Shear Stresses

AbstractIn this study, finite element modeling of composite beams with distributed piezoelectric sensors and actuators which is based upon a coupled electromechanical model has been considered. For modeling of mechanical displacement through the thickness, a sinus model that satisfies continuity conditions of transverse shear stresses and the boundary conditions on the upper and lower surfaces of the beam has been employed. In the presented model, the number of unknowns is not dependent on the number of layers. The variation of electric potential in each piezoelectric layer has been modeled using layer-wise theory. By applying the virtual work principle (VWP), a formulation has been developed for a twonodded Hermitian-2(n + 1) layer-wise nodded element for a n-layered beam. The VWP leads to a derivation that could include dynamic analysis. However, in this study only static problems have been considered. Comparison of results obtained from this formulation with available works in the literature, demonstrates efficiency of proposed model in analysis of laminated beams under mechanical and electrical loadings.

Crystal Plasticity Finite Element Modelling of BCC Deformation Texture in Cold Rolling

2008 ◽  
Vol 32 ◽  
pp. 251-254 ◽  
Author(s):  
Hei Jie Li ◽  
Jing Tao Han ◽  
Zheng Yi Jiang ◽  
Hua Chun Pi ◽  
Dong Bin Wei ◽  
...  
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Crystal Plasticity ◽  
Finite Element Modelling ◽  
Rolling Texture ◽  
Element Model ◽  
Deformation Texture ◽  
Type Model ◽  
Element Modelling ◽  
Crystal Plasticity Finite Element

Taylor-type and finite element polycrstal models have been embedded into the commercial finite element code ABAQUS to carry out the crystal plasticity finite element modelling of BCC deformation texture based on rate dependent crystal constitutive equations. Initial orientations measured by EBSD were directly used in crystal plasticity finite element model to simulate the development of rolling texture of IF steel under various reductions. The calculated results are in good agreement with the experimental values. The predicted and measured textures tend to sharper with an increase of reduction, and the texture obtained from the Taylor-type model is much stronger than that by finite element model. The rolling textures calculated with 48 {110}<110>, {112}<111> and {123}<111> slip systems are close to the EBSD results.

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