scholarly journals Numerical model of solidification process of Fe-C alloy taking into account the phenomenon of shrinkage cavity formation

2019 ◽  
Vol 254 ◽  
pp. 02009
Author(s):  
Tomasz Skrzypczak ◽  
Ewa Węgrzyn-Skrzypczak ◽  
Leszek Sowa
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Models ◽  
Three Dimensional ◽  
Solidification Process ◽  
Shrinkage Cavity ◽  
Cavity Formation ◽  
The Finite Element Method ◽  
Computer Calculations ◽  
Solidification Problem

Mathematical and numerical models of Fe-C alloy solidification process based on the finite element method (FEM) are presented in the paper. The phenomenon of the defect called "shrinkage cavity" is introduced to the model. It is very important aspect of presented work which makes possible the prediction of the location and shape of mentioned defect depending on the geometry of the casting and cooling condition of the process. An original computer program using Visual C++ environment has been written in order to simulate described process. The results of computer calculations of the three-dimensional solidification problem of the casting with riser are presented and discussed in details.

A Three-Dimensional Numerical Analysis on the Effective Permittivity of Composites Including Ellipsoids

2013 ◽  
Vol 483 ◽  
pp. 23-27
Author(s):  
De Yuan Zhang ◽  
Li Ming Yuan ◽  
Yong Gang Xu ◽  
Jun Cai
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Numerical Models ◽  
Effective Permittivity ◽  
Three Dimensional ◽  
Comsol Multiphysics ◽  
Three Dimension ◽  
The Finite Element Method ◽  
Modeling Software ◽  
Element Method

To investigate the effective permittivity of composites composed of ellipsoidal inclusions, three-dimension numerical models for ellipsoidal inclusions distributed randomly are built with the finite-element modeling software Comsol Multiphysics. After calculating the effective permittivity for different cases and comparing the results with analytical results from the Maxwell-Garnett mixing rule, we find that the finite-element method has an advantage in detecting details of the interaction among inclusions, which have some impacts on the effective permittivity and could not be accurately taken into account in the analytical model. The finite-element method is expected to solve more complex problems on electromagnetic computation.

Comparison of Conventional and Pontic Fixed Partial Dentures Over Implants Using the Finite Element Method: Three-Dimensional Analysis of Cortical and Medullary Bone Stress

2020 ◽  
Vol 46 (3) ◽  
pp. 175-181
Author(s):  
Marcelo Bighetti Toniollo ◽  
Mikaelly dos Santos Sá ◽  
Fernanda Pereira Silva ◽  
Giselle Rodrigues Reis ◽  
Ana Paula Macedo ◽  
...  
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Medullary Bone ◽  
Principal Stresses ◽  
Bone Stress ◽  
Bone Damage ◽  
Rehabilitation System ◽  
Minimum Requirements

Rehabilitation with implant prostheses in posterior areas requires the maximum number of possible implants due to the greater masticatory load of the region. However, the necessary minimum requirements are not always present in full. This project analyzed the minimum principal stresses (TMiP, representative of the compressive stress) to the friable structures, specifically the vestibular face of the cortical bone and the vestibular and internal/lingual face of the medullary bone. The experimental groups were as follows: the regular splinted group (GR), with a conventional infrastructure on 3 regular-length Morse taper implants (4 × 11 mm); and the regular pontic group (GP), with a pontic infrastructure on 2 regular-length Morse taper implants (4 × 11 mm). The results showed that the TMiP of the cortical and medullary bones were greater for the GP in regions surrounding the implants (especially in the cervical and apical areas of the same region) but they did not reach bone damage levels, at least under the loads applied in this study. It was concluded that greater stress observed in the GP demonstrates greater fragility with this modality of rehabilitation; this should draw the professional's attention to possible biomechanical implications. Whenever possible, professionals should give preference to use of a greater number of implants in the rehabilitation system, with a focus on preserving the supporting tissue with the generation of less intense stresses.

Towards Predicting Relative Belt Edge Endurance With the Finite Element Method

1990 ◽  
Vol 18 (4) ◽  
pp. 216-235 ◽  
Author(s):  
J. De Eskinazi ◽  
K. Ishihara ◽  
H. Volk ◽  
T. C. Warholic
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Shear Deformations ◽  
Element Analysis ◽  
Vertical Loading ◽  
Predicted Values ◽  
Element Method

Abstract The paper describes the intention of the authors to determine whether it is possible to predict relative belt edge endurance for radial passenger car tires using the finite element method. Three groups of tires with different belt edge configurations were tested on a fleet test in an attempt to validate predictions from the finite element results. A two-dimensional, axisymmetric finite element analysis was first used to determine if the results from such an analysis, with emphasis on the shear deformations between the belts, could be used to predict a relative ranking for belt edge endurance. It is shown that such an analysis can lead to erroneous conclusions. A three-dimensional analysis in which tires are modeled under free rotation and static vertical loading was performed next. This approach resulted in an improvement in the quality of the correlations. The differences in the predicted values of various stress analysis parameters for the three belt edge configurations are studied and their implication on predicting belt edge endurance is discussed.

The Convergence of the H-P Version of the Finite Element Method with Quasi-Uniform Meshes for Three Dimensional Poisson Problems with Edge Singularity

2014 ◽  
Vol 644-650 ◽  
pp. 1551-1555
Author(s):  
Jian Ming Zhang ◽  
Yong He
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Weighted Sobolev Spaces ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Smooth Functions ◽  
Edge Singularity ◽  
Theoretical Predictions ◽  
Theoretical Results ◽  
Element Method

This paper is concerned with the convergence of the h-p version of the finite element method for three dimensional Poisson problems with edge singularity on quasi-uniform meshes. First, we present the theoretical results for the convergence of the h-p version of the finite element method with quasi-uniform meshes for elliptic problems on polyhedral domains on smooth functions in the framework of Jacobi-weighted Sobolev spaces. Second, we investigate and analyze numerical results for three dimensional Poission problems with edge singularity. Finally, we verified the theoretical predictions by the numerical computation.

scholarly journals Finite-Element Simulation of the Barnes Ice Cap

1979 ◽  
Vol 24 (90) ◽  
pp. 489-490 ◽  
Author(s):  
J. J. Emery ◽  
E. A. Hanafy ◽  
G. H. Holdsworth ◽  
F. Mirza
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Simulation Model ◽  
Feasibility Study ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Ice Cap ◽  
Stress Dependent ◽  
Analytical Approaches ◽  
Element Method

Abstract The finite-element method is being used to simulate glacier flow problems, with particular emphasis on the surge behaviour of the Barnes Ice Cap, Baffin Island. Following an advanced feasibility study to determine the influence of major factors such as bed topography and flow relationships, a refined simulation model is being developed to incorporate realistically: the thermal regime of the ice mass; large deformations during flow and sliding; basal sliding zones; a temperature and stress dependent ice flow relationship; mass balance; and three-dimensional influences. The findings of the advanced feasibility study on isothermal, steady-state flow of the Barnes Ice Cap are presented in the paper before turning to a detailed discussion of the refined simulation model and its application to surging. It is clear that the finite-element method allows necessary refinements not available to analytical approaches.

A Method for Obtaining a Three-Dimensional Geometric Model of Dental Implants for Analysis via the Finite Element Method

2013 ◽  
Vol 22 (3) ◽  
pp. 309-314 ◽  
Author(s):  
Guilherme Carvalho Silva ◽  
Tulimar Machado Pereira Cornacchia ◽  
Estevam Barbosa de Las Casas ◽  
Cláudia Silami de Magalhães ◽  
Allyson Nogueira Moreira
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Dental Implants ◽  
Geometric Model ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Element Method

Finite Element Models for Flexible Cosserat Solids

2020 ◽  
Author(s):  
Olivier A. Bauchau ◽  
Minghe Shan
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Displacement Vector ◽  
Equations Of Motion ◽  
Three Dimensional ◽  
The Finite Element Method ◽  
Discrete Equations ◽  
Computation Efficiency ◽  
Elasticity Problems ◽  
Element Method

Abstract The application of the finite element method to the modeling of Cosserat solids is investigated in detail. In two- and three-dimensional elasticity problems, the nodal unknowns are the components of the displacement vector, which form a linear field. In contrast, when dealing with Cosserat solids, the nodal unknowns form the special Euclidean group SE(3), a nonlinear manifold. This observation has numerous implications on the implementation of the finite element method and raises numerous questions: (1) What is the most suitable representation of this nonlinear manifold? (2) How is it interpolated over one element? (3) How is the associated strain field interpolated? (4) What is the most efficient way to obtain the discrete equations of motion? All these questions are, of course intertwined. This paper shows that reliable schemes are available for the interpolation of the motion and curvature fields. The interpolated fields depend on relative nodal motions only, and hence, are both objective and tensorial. Because these schemes depend on relative nodal motions only, only local parameterization is required, thereby avoiding the occurrence of singularities. For Cosserat solids, it is preferable to perform the discretization operation first, followed by the variation operation. This approach leads to considerable computation efficiency and simplicity.

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