Validation of an Improved Contact Method for Multi-Material Eulerian Hydrocodes in Three-Dimensions

2019 ◽  
Author(s):  
Kenneth C. Walls ◽  
David L. Littlefield
Keyword(s):  
Finite Element ◽  
Large Deformations ◽  
Three Dimensions ◽  
Contact Method ◽  
Arbitrary Lagrangian Eulerian ◽  
Aspect Ratios ◽  
Ale Methods ◽  
Lagrangian Finite Element ◽  
Multiple Materials ◽  
Natural Description

Abstract Realistic and accurate modeling of contact for problems involving large deformations and severe distortions presents a host of computational challenges. Due to their natural description of surfaces, Lagrangian finite element methods are traditionally used for problems involving sliding contact. However, problems such as those involving ballistic penetrations, blast-structure interactions, and vehicular crash dynamics, can result in elements developing large aspect ratios, twisting, or even inverting. For this reason, Eulerian, and by extension Arbitrary Lagrangian-Eulerian (ALE), methods have become popular. However, additional complexities arise when these methods permit multiple materials to occupy a single finite element.

Research and Development of the Porthole-Die Aluminium Alloy Extrusion Processes

2012 ◽  
Vol 472-475 ◽  
pp. 214-218
Author(s):  
Shu Mei Lou ◽  
Lin Jing Xiao
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Research And Development ◽  
Aluminium Alloy ◽  
Simulation Method ◽  
Empirical Method ◽  
Arbitrary Lagrangian Eulerian ◽  
Porthole Die ◽  
Lagrangian Finite Element ◽  
Volume Method

The current research on the porthole-die aluminium alloy extrusion is presented here. The empirical method and simulation method are analyzed. Particularly, the Lagrangian Finite Element Method(FEM), Eulerian Finite Volume Method(FVM) and Arbitrary-Lagrangian Eulerian(ALE) algorithm are compared. The development of the porthole-die aluminium is educed.

Analysis of Soil Penetration Problems by High-Order Elements

2014 ◽  
Vol 553 ◽  
pp. 401-404 ◽  
Author(s):  
Majidreza Nazem ◽  
John Phillip Carter ◽  
Mina Kardani
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Large Deformations ◽  
Significant Loss ◽  
High Order ◽  
Analysis Time ◽  
Arbitrary Lagrangian Eulerian ◽  
Triangular Elements ◽  
Inertia Forces ◽  
Element Method

This paper addresses the application of high-order elements in the analysis of soil penetration problems, particularly those involving inertia forces and large deformations. Among others, 15-node triangular elements are formulated within an Arbitrary Lagrangian-Eulerian finite element method. Preliminary studies indicate that high-order elements can significantly decrease the analysis time without significant loss of accuracy.

scholarly journals A finite element for laminar flow of incompressible fluids with inertia effects and thermomechanical coupling

2010 ◽  
pp. 293-304
Author(s):  
Thomas Heuzé ◽  
Jean-Baptiste Leblond ◽  
Jean-Michel Bergheau ◽  
Éric Feulvarch
Keyword(s):  
Finite Element ◽  
Spot Welding ◽  
Large Deformations ◽  
Friction Stir Spot Welding ◽  
Incompressible Fluids ◽  
Thermomechanical Coupling ◽  
Arbitrary Lagrangian Eulerian ◽  
Inertia Effects ◽  
Friction Stir ◽  
Velocity Pressure

The Friction Stir Spot Welding (FSSW) process involves large deformations in the neighborhood of the tool. The simulation of this process has to account for a pasty phase in which the material is stirred, and a phase remaining solid. An Arbitrary Lagrangian Eulerian (ALE) approach combined with respectively fluid and solid behaviours in each of those phases may allow to simulate a lot of rotations of the tool into the material while following the boundaries of the sheets. This work focuses on a first stage of this study, the development of a mixed formulation temperature/velocity/pressure of a fluid finite element P1+/P1 in the unsteady case.

IMPLEMENTATION OF THE EULERIAN AND THE ARBITRARY LAGRANGIAN–EULERIAN DESCRIPTIONS IN FINITE ELEMENT SIMULATION OF EXTRUSION PROCESSES

2013 ◽  
Vol 02 (03n04) ◽  
pp. 1350013
Author(s):  
ALIASGHAR ASGARI ◽  
ALI NAYEBI
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Arbitrary Lagrangian Eulerian ◽  
Governing Equations ◽  
Split Method ◽  
Element Simulation ◽  
Ale Methods ◽  
Eulerian Descriptions ◽  
Operator Split ◽  
Good Agreement

In this paper, backward and forward–backward-radial extrusion processes of aluminum have been simulated using finite element method. Due to the extreme deformation of the workpiece and the restrictions of the Lagrangian approach to simulate such problems, the arbitrary Lagrangian–Eulerian (ALE) and the Eulerian descriptions have been implemented in backward and forward–backward-radial extrusion processes, respectively. Operator-split method is used to solve the coupled governing equations of the Eulerian and the ALE formulations. To validate the finite element simulations, the results have been compared with experimental data in terms of extrusion load and geometry of final products. A good agreement has been seen between the results demonstrating the capability of the Eulerian and the ALE methods on finite element simulation of extrusion processes.

Large deformation analysis of suction caisson installation in clay

2006 ◽  
Vol 43 (12) ◽  
pp. 1344-1357 ◽  
Author(s):  
Hongjie Zhou ◽  
Mark F Randolph
Keyword(s):  
Finite Element ◽  
Large Deformation ◽  
Deformation Analysis ◽  
Arbitrary Lagrangian Eulerian ◽  
Depth Of Penetration ◽  
Suction Caisson ◽  
Tip Resistance ◽  
Stress Changes ◽  
Ale Methods ◽  
The Difference

Large deformation finite element (LDFE) analyses were performed to study the installation of caissons by suction and jacking in normally consolidated clay. The penetration of the caisson wall was modelled between depths of one and four diameters using an axisymmetric LDFE approach, which falls in the category of arbitrary Lagrangian–Eulerian (ALE) methods. The results allowed quantification of differences in the behaviour of caissons installed entirely by jacking compared with a combination of self-weight and suction as is used in the field. For jacked installation, over the penetration range of one to four diameters, the proportion of caisson wall accommodated by inward soil flow reduced from around 45% at the start to zero at about four diameters embedment; by contrast, the proportion for suction installation stayed essentially constant, oscillating around 65% through the depth of penetration. This difference was also evident in the local incremental displacements of the soil beneath the caisson tip. During continuous penetration, the induced increases in radial and mean total stresses around the caisson wall are some 10%–15% smaller for suction installation than for jacked installation, with the difference growing with increasing penetration. In addition, an obvious difference was found in the caisson tip resistance between these two installation methods.Key words: suction caisson, clay, large deformation finite element, soil plug, total stress changes, penetration resistance, factor of safety.

Calculating Energy Release Rate as a Function of Crack Length Using a Multiple-Step Crack Closure Technique in Tire Finite Element Models

2018 ◽  
Vol 46 (3) ◽  
pp. 130-152
Author(s):  
Dennis S. Kelliher
Keyword(s):  
Finite Element ◽  
Energy Release Rate ◽  
Crack Length ◽  
Energy Release ◽  
Crack Closure ◽  
Release Rate ◽  
Fatigue Behavior ◽  
Three Dimensions ◽  
Quantitative Prediction ◽  
Closure Technique

ABSTRACT When performing predictive durability analyses on tires using finite element methods, it is generally recognized that energy release rate (ERR) is the best measure by which to characterize the fatigue behavior of rubber. By addressing actual cracks in a simulation geometry, ERR provides a more appropriate durability criterion than the strain energy density (SED) of geometries without cracks. If determined as a function of crack length and loading history, and augmented with material crack growth properties, ERR allows for a quantitative prediction of fatigue life. Complications arise, however, from extra steps required to implement the calculation of ERR within the analysis process. This article presents an overview and some details of a method to perform such analyses. The method involves a preprocessing step that automates the creation of a ribbon crack within an axisymmetric-geometry finite element model at a predetermined location. After inflating and expanding to three dimensions to fully load the tire against a surface, full ribbon sections of the crack are then incrementally closed through multiple solution steps, finally achieving complete closure. A postprocessing step is developed to determine ERR as a function of crack length from this enforced crack closure technique. This includes an innovative approach to calculating ERR as the crack length approaches zero.

A Finite Element Approach to the Transient Dynamics of Rolling Tires with Emphasis on Rolling Noise Simulation4

2007 ◽  
Vol 35 (3) ◽  
pp. 165-182 ◽  
Author(s):  
Maik Brinkmeier ◽  
Udo Nackenhorst ◽  
Heiner Volk
Keyword(s):  
Finite Element ◽  
Traffic Noise ◽  
Complex Eigenvalue ◽  
Arbitrary Lagrangian Eulerian ◽  
Finite Element Approach ◽  
Road Systems ◽  
Element Approach ◽  
Road Surface Roughness ◽  
Complex Eigenvalue Analysis ◽  
Rolling Noise

Abstract The sound radiating from rolling tires is the most important source of traffic noise in urban regions. In this contribution a detailed finite element approach for the dynamics of tire/road systems is presented with emphasis on rolling noise prediction. The analysis is split into sequential steps, namely, the nonlinear analysis of the stationary rolling problem within an arbitrary Lagrangian Eulerian framework, and a subsequent analysis of the transient dynamic response due to the excitation caused by road surface roughness. Here, a modal superposition approach is employed using complex eigenvalue analysis. Finally, the sound radiation analysis of the rolling tire/road system is performed.

Effect of crack on free vibration of a pre-stressed curved plate

2021 ◽  
pp. 095440622199486
Author(s):  
Can Gonenli ◽  
Hasan Ozturk ◽  
Oguzhan Das
Keyword(s):  
Finite Element ◽  
Free Vibration ◽  
Natural Frequency ◽  
Present Model ◽  
Mode Shapes ◽  
Load Parameter ◽  
Flexible Plate ◽  
Cantilever Plate ◽  
Finite Element Software ◽  
Aspect Ratios

In this study, the effect of crack on free vibration of a large deflected cantilever plate, which forms the case of a pre-stressed curved plate, is investigated. A distributed load is applied at the free edge of a thin cantilever plate. Then, the loading edge of the deflected plate is fixed to obtain a pre-stressed curved plate. The large deflection equation provides the non - linear deflection curve of the large deflected flexible plate. The thin curved plate is modeled by using the finite element method with a four-node quadrilateral element. Three different aspect ratios are used to examine the effect of crack. The effect of crack and its location on the natural frequency parameter is given in tables and graphs. Also, the natural frequency parameters of the present model are compared with the finite element software results to verify the reliability and validity of the present model. This study shows that the different mode shapes are occurred due to the change of load parameter, and these different mode shapes cause a change in the effect of crack.

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