Homogenized finite element models can accurately predict screw pull-out in continuum materials, but not in porous materials

Simple spot weld connection models are desirable in huge and complicated finite element models of automotive body-in-white structures which generally contains thousands of spot weld joints. Hence, in this paper six different individual spot weld joint finite element models simplified in terms of their geometric and constitutive representations were developed including the one that is currently used in automotive industries. The stiffness characteristics of these developed models were compared with the experimental results obtained following a simple strategy to design the welded joint based on the desired mode of nugget pull out failure. It was found that the current spot weld modeling practice in automotive industry under predict the maximum joint strength nearly by 50% for different loading conditions. The computational costs incurred by the developed models in different loading conditions were also compared. Hence, a suitable model for spot welded joints is established which is very simple to develop but relatively cheap in terms of computational costs.

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Analysis of a Liquid Filled Poroelastic Cylinder Exposed to a Time Varying Pressure Load

Volume 9: Mechanics of Solids, Structures and Fluids; NDE, Structural Health Monitoring and Prognosis ◽

10.1115/imece2017-71006 ◽

2017 ◽

Author(s):

Tyler L. Ceste ◽

Sridhar Santhanam ◽

Gerard F. Jones

Keyword(s):

Finite Element ◽

Porous Materials ◽

Energy Absorption ◽

Solid Phase ◽

Dynamic Compression ◽

Analytical Models ◽

Finite Element Models ◽

Porous Cylinder ◽

Linear Effect ◽

Non Linear

Porous materials are of interest for a number of applications one of them being energy absorption. These materials offer the ability to absorb more energy than a typical metallic solid and thus provide an opportunity to improve the performance of structures that endure blast loads. These structures undergo very large loads in very short periods of time and therefore maximizing energy absorption is paramount. This study seeks to improve the understanding of the response of porous materials by developing both analytical and finite element models for a liquid filled porous cylinder exposed to a dynamic compression loading. The poroelastic cylinder consists of a porous metallic solid phase and a viscous liquid phase. These two phases provide for two mechanisms of energy dissipation which are that of the deformation of the solid and the viscous flow of the liquid. The theories of elasticity and porous media were used to formulate the governing equations for the liquid filled porous cylinder. These equations describe the coupling between the displacements of the solid cylinder and the pressure distribution of the liquid. Analytical and finite element models were developed to predict the cylinders response in order to determine the amount of energy absorbed when the cylinder is exposed to a dynamic compression load. Analytical models were developed to validate the finite element results. As more complexity is added to this problem an analytical approach becomes unviable and a finite element approach must be used. One such complexity that can be considered is the effect of utilizing a non-constant liquid viscosity, which requires developing a non-linear finite element model to account for the viscositys dependence on strain rate. This added non-linear effect should allow for additional viscous energy to be absorbed and thus can further enhance the performance of the system.

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Tapering Effects on the Installation of Suction Caissons in Clay

Volume 2: Structures, Safety and Reliability ◽

10.1115/omae2008-57583 ◽

2008 ◽

Cited By ~ 1

Author(s):

Mostafa Zeinoddini ◽

Woorya H. Shariati ◽

Mahmood Nabipour

Keyword(s):

Finite Element ◽

Finite Element Models ◽

Finite Element Approach ◽

Pull Out ◽

Full Penetration ◽

Element Approach ◽

Numerical Finite Element ◽

Wall Slope ◽

Suction Caissons ◽

Considerable Enhancement

This paper reports results from an investigation on the tapering effects on the installation and pull-out performance of suction caissons. A numerical finite element approach has been used for the study. The finite element models have first been calibrated/verified against several available experimental data for the installation of the upright suction caissons in clay. The verified models have then been used to examine the behaviour of the tapered suction caissons during the pull-out and installation phases. Numerical results indicate that tapered caissons present considerable enhancement in their pull-out capacity comparing to those from corresponding upright caissons. Also it has been noticed that in general tapered caissons of positive wall slopes need extra forces, in comparison to their equivalent upright caissons, to achieve a full penetration. However, at least with those models studied, these extra forces have found to be less than twenty five percent when the wall slope varies from zero (upright) to 15%. This is while the additional pull-out capacities that might be achieved from these tapered suction caissons could reach to several hundred percents. An almost linear relationship has been observed between the total installation force and the caisson’s wall slope.

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Maximum Principle in Finite Element Models for Convection-Diffusion Phenomena

10.1016/s0304-0208(08)x7173-7 ◽

1983 ◽

Keyword(s):

Finite Element ◽

Maximum Principle ◽

Finite Element Models ◽

Convection Diffusion ◽

Diffusion Phenomena

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Internal Variable and Cellular Automata-Finite Element Models of Heat Treatment

International Journal for Multiscale Computational Engineering ◽

10.1615/intjmultcompeng.v8.i3.40 ◽

2010 ◽

Vol 8 (3) ◽

pp. 267-285 ◽

Cited By ~ 8

Author(s):

Piotr Maciol ◽

Jerzy Gawad ◽

Roman Kuziak ◽

Maciej Pietrzyk

Keyword(s):

Heat Treatment ◽

Finite Element ◽

Cellular Automata ◽

Internal Variable ◽

Finite Element Models

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A Finite Element Analysis of the General Rolling Contact Problem for a Viscoelastic Rubber Cylinder

Tire Science and Technology ◽

10.2346/1.2148795 ◽

1988 ◽

Vol 16 (1) ◽

pp. 18-43 ◽

Cited By ~ 10

Author(s):

J. T. Oden ◽

T. L. Lin ◽

J. M. Bass

Keyword(s):

Finite Element ◽

Variational Principles ◽

Standing Waves ◽

Rolling Contact ◽

Finite Element Models ◽

Viscoelastic Cylinder ◽

Element Analysis ◽

Elastic Rubber ◽

Frictional Effects ◽

Rough Foundation

Abstract Mathematical models of finite deformation of a rolling viscoelastic cylinder in contact with a rough foundation are developed in preparation for a general model for rolling tires. Variational principles and finite element models are derived. Numerical results are obtained for a variety of cases, including that of a pure elastic rubber cylinder, a viscoelastic cylinder, the development of standing waves, and frictional effects.

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