Parameter Effects on Dynamic Crushing Behavior of Aluminum Staggered Kelvin Cellular Metal

2014 ◽  
Vol 703 ◽  
pp. 385-389 ◽  
Author(s):  
Xiao Bing Dang ◽  
Kai He ◽  
Jiu Hua Li ◽  
Qi Yang Zuo ◽  
Ru Xu Du
Keyword(s):  
Finite Element ◽  
Base Material ◽  
Element Model ◽  
Edge Length ◽  
Shell Elements ◽  
Structure Characteristics ◽  
Cellular Metal ◽  
Crushing Behavior ◽  
Full Factorial ◽  
Dynamic Crushing

This paper is aimed at investigating the parameter effects on dynamic crushing behavior of staggered Kelvin cellular metal using finite element method. The geometrical characteristics of the staggered cellular structure were analyzed and the finite element model was constructed using shell elements. A full factorial Design of Experiment simulation was carried out and four individual factors including two structure characteristics of the cellular metals and two mechanical parameters of the base material were selected, namely cell edge length, cell wall thickness, yield stress and tangent modulus. Their single and interaction effects on plateau stress, densification strain and densification strain energy were mainly researched. From the results it could be seen that the structure characteristics were a little more important than the base material properties for aluminum staggered Kelvin cellular metal.

Finite Element Modeling of Unidirectional Non-Crimp Fabric for Manufacturing of Composites with Embedded Cabling

2013 ◽  
Vol 554-557 ◽  
pp. 484-491 ◽  
Author(s):  
Alexander S. Petrov ◽  
James A. Sherwood ◽  
Konstantine A. Fetfatsidis ◽  
Cynthia J. Mitchell
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Element Model ◽  
Explicit Finite Element ◽  
Shell Elements ◽  
Beam Elements ◽  
Hybrid Finite Element ◽  
International Benchmarking ◽  
Unidirectional Glass ◽  
Forming Simulations

A hybrid finite element discrete mesoscopic approach is used to model the forming of composite parts using a unidirectional glass prepreg non-crimp fabric (NCF). The tensile behavior of the fabric is represented using 1-D beam elements, and the shearing behavior is captured using 2-D shell elements into an ABAQUS/Explicit finite element model via a user-defined material subroutine. The forming of a hemisphere is simulated using a finite element model of the fabric, and the results are compared to a thermostamped part as a demonstration of the capabilities of the used methodology. Forming simulations using a double-dome geometry, which has been used in an international benchmarking program, were then performed with the validated finite element model to explore the ability of the unidirectional fabric to accommodate the presence of interlaminate cabling.

scholarly journals An Efficient and General Finite Element Model for Double-Sided Incremental Forming

2016 ◽  
Vol 138 (9) ◽  
Author(s):  
Newell Moser ◽  
David Pritchet ◽  
Huaqing Ren ◽  
Kornel F. Ehmann ◽  
Jian Cao
Keyword(s):  
Finite Element ◽  
Incremental Forming ◽  
Mesh Size ◽  
Element Model ◽  
Explicit Finite Element ◽  
Fully Integrated ◽  
Shell Elements ◽  
Mass Scaling ◽  
Element Simulation ◽  
Element Type

Double-sided incremental forming (DSIF) is a subcategory of general incremental sheet forming (ISF), and uses tools above and below a sheet of metal to squeeze and bend the material into freeform geometries. Due to the relatively slow nature of the DSIF process and the necessity to capture through-thickness mechanics, typical finite element simulations require weeks or even months to finish. In this study, an explicit finite element simulation framework was developed in LS-DYNA using fully integrated shell elements in an effort to lower the typical simulation time while still capturing the mechanics of DSIF. The tool speed, mesh size, element type, and amount of mass scaling were each varied in order to achieve a fast simulation with minimal sacrifice regarding accuracy. Using 8 CPUs, the finalized DSIF model simulated a funnel toolpath in just one day. Experimental strains, forces, and overall geometry were used to verify the simulation. While the simulation forces tended to be high, the trends were still well captured by the simulation model. The thickness and in-plane strains were found to be in good agreement with the experiments.

Finite Element Prediction of Mechanical Behaviour under Bending of Honeycomb Sandwich Panels

2014 ◽  
Vol 980 ◽  
pp. 81-85 ◽  
Author(s):  
Kaoua Sid-Ali ◽  
Mesbah Amar ◽  
Salah Boutaleb ◽  
Krimo Azouaoui
Keyword(s):  
Finite Element ◽  
Mechanical Behaviour ◽  
Three Dimensional ◽  
Sandwich Panels ◽  
Element Model ◽  
Shell Elements ◽  
Numerical Characterization ◽  
Bending Load ◽  
Accurate Stress Analysis ◽  
Three Dimensional Finite Element

This paper outlines a finite element procedure for predicting the mechanical behaviour under bending of sandwich panels consisting of aluminium skins and aluminium honeycomb core. To achieve a rapid and accurate stress analysis, the sandwich panels have been modelled using shell elements for the skins and the core. Sandwich panels were modelled by a three-dimensional finite element model implemented in Abaqus/Standard. By this model the influence of the components on the behaviour of the sandwich panel under bending load was evaluated. Numerical characterization of the sandwich structure, is confronted to both experimental and homogenization technique results.

Application of a Shell-Spring Model for the Optimization of Radial Tire Contour Using a Genetic Algorithm

2003 ◽  
Vol 31 (1) ◽  
pp. 39-63 ◽  
Author(s):  
G. Unnithan ◽  
R. KrishnaKumar ◽  
A. Prasad
Keyword(s):  
Genetic Algorithm ◽  
Finite Element ◽  
Optimization Problems ◽  
Optimization Procedure ◽  
Element Model ◽  
Spring Model ◽  
New Approach ◽  
Shell Elements ◽  
Complex Optimization ◽  
Profile Optimization

Abstract Optimization gives a new facet to design and development of tires. A new approach to the tire profile optimization is proposed in this study. The optimization procedure is integrated with a simple shell-spring finite element model for faster evaluation. In the shell-spring model, the shell elements represent the tire carcass, whereas the tread is represented by the spring elements. This is applied for the optimization of the tire contour for better maneuverability. The genetic algorithm, an evolutionary optimization procedure that is robust and efficient in solving complex optimization problems, is chosen. A new tire contour is obtained that improves tire maneuverability by increasing the sidewall belt tension.

Quick Aeromechanical Assessment of Turbine Blades Based on Shell Element Based Models

2014 ◽  
Author(s):  
Suryarghya Chakrabarti ◽  
Letian Wang ◽  
K. M. K. Genghis Khan
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Natural Frequencies ◽  
Turbine Blades ◽  
Computation Time ◽  
Shell Element ◽  
Element Model ◽  
Shell Elements ◽  
Barrier Coating ◽  
Order Of Magnitude

A fast finite element model based tool has been developed to calculate the natural frequencies of fundamental modes of cooled gas turbine bladed disk assemblies during conceptual design. The tool uses shell elements to model the airfoil, shank, and disk, and achieves order of magnitude reduction in computation time allowing exploration of a wide design space at the preliminary design stages. The analysis includes prestress effects due to centrifugal loading and approximate temperature loading on the parts. Sensitivity studies are performed to understand the relative impact of design features such as airfoil internal geometry, bond coat, and thermal barrier coating on the system natural frequencies. Critical features are selected which need to be modeled to get an accurate natural frequency estimate. The results obtained are shown to be within 5% of the frequencies obtained from a full-fidelity finite element model. A case study performed on seven blade designs illustrates the use of this tool for quick aeromechanical assessment of a large number of designs.

Seismic analysis of elevated pure conical tanks under vertical excitation

2014 ◽  
Vol 41 (10) ◽  
pp. 909-917 ◽  
Author(s):  
Michael Jolie ◽  
Ayman M. El Ansary ◽  
Ashraf A. El Damatty
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Seismic Analysis ◽  
Three Dimensional ◽  
Vertical Component ◽  
Element Model ◽  
Shell Elements ◽  
Vertical Excitation ◽  
Analysis And Design ◽  
Conical Tanks

Truncated conical vessels are commonly used as liquid containers in elevated tanks. Despite the widespread use of this type of structure worldwide, no direct code provisions are currently available covering its seismic analysis and design. The purpose of the current study is to assess the importance of considering the vertical component of ground accelerations when analyzing and designing this type of water-storage structure. The study is conducted using an equivalent mechanical model that estimates the normal forces that develop in the tank walls when subjected to vertical excitation. In addition, a three-dimensional finite element model has been developed by modeling the walls of the tank using shell elements. The finite element model has been employed to predict maximum membrane and overall meridional stresses due to both hydrodynamic and hydrostatic pressure distributions. Comparisons have been conducted to assess the significance of considering vertical excitation and to identify the magnification in meridional stresses due to bending effects associated with support conditions and large deformations.

scholarly journals Finite Element Analysis of the Stress Field in Peri-Implant Bone: A Parametric Study of Influencing Parameters and Their Interactions for Multi-Objective Optimization

2020 ◽  
Vol 10 (17) ◽  
pp. 5973
Author(s):  
Paul Didier ◽  
Boris Piotrowski ◽  
Gael Le Coz ◽  
David Joseph ◽  
Pierre Bravetti ◽  
...  
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Young’S Modulus ◽  
Load Transfer ◽  
Young's Modulus ◽  
Element Model ◽  
Implant Design ◽  
Main Effects ◽  
Full Factorial ◽  
Surrounding Bone

The present work proposes a parametric finite element model of the general case of a single loaded dental implant. The objective is to estimate and quantify the main effects of several parameters on stress distribution and load transfer between a loaded dental implant and its surrounding bone. The interactions between them are particularly investigated. Seven parameters (implant design and material) were considered as input variables to build the parametric finite element model: the implant diameter, length, taper and angle of inclination, Young’s modulus, the thickness of the cortical bone and Young’s modulus of the cancellous bone. All parameter combinations were tested with a full factorial design for a total of 512 models. Two biomechanical responses were identified to highlight the main effects of the full factorial design and first-order interaction between parameters: peri-implant bone stress and load transfer between bones and implants. The description of the two responses using the identified coefficients then makes it possible to optimize the implant configuration in a case study with type IV. The influence of the seven considered parameters was quantified, and objective information was given to support surgeon choices for implant design and placement. The implant diameter and Young’s modulus and the cortical thickness were the most influential parameters on the two responses. The importance of a low Young’s modulus alloy was highlighted to reduce the stress shielding between implants and the surrounding bone. This method allows obtaining optimized configurations for several case studies with a custom-made design implant.

Mesh Convergence Studies for Thick Shell Elements Developed by the ASME Special Working Group on Computational Modeling

2013 ◽  
Author(s):  
David P. Molitoris ◽  
Gordon S. Bjorkman ◽  
Chi-Fung Tso ◽  
Michael Yaksh
Keyword(s):  
Finite Element ◽  
Plastic Strain ◽  
Finite Element Model ◽  
Working Group ◽  
Element Model ◽  
Thick Shell ◽  
Shell Elements ◽  
Special Working ◽  
Special Working Group

The ASME Special Working Group on Computational Modeling for Explicit Dynamics was founded in August 2008 for the purpose of creating a quantitative guidance document for the development of finite element models used to analyze energy-limited events using explicit dynamics software. This document will be referenced in the ASME Code Section III, Division 3 and the next revision of NRC Regulatory Guide 7.6 as a means by which the quality of a finite element model may be judged. One portion of the document will be devoted to a series of element convergence studies that can aid designers in establishing the mesh refinement requirements necessary to achieve accurate results for a variety of different element types in regions of high plastic strain. These convergence studies will also aid reviewers in evaluating the quality of a finite element model and the apparent accuracy of its results. In this paper, the authors present the results of a convergence study for an impulsively loaded propped cantilever beam constructed of LS-DYNA thick shell elements using both reduced and selectively reduced integration. A large load is applied to produce large deformations and large plastic strains in the beam. The deformation and plastic strain results are then compared to similar results obtained using thin shell elements and hexahedral elements for the beam mesh.

Analysis of Tire Force and Moment Response During Side Slip Using an Efficient Finite Element Model

2002 ◽  
Vol 30 (2) ◽  
pp. 66-82 ◽  
Author(s):  
I. Darnell ◽  
R. Mousseau ◽  
G. Hulbert
Keyword(s):  
Finite Element ◽  
Flat Surface ◽  
Element Model ◽  
Stress Fields ◽  
Tire Model ◽  
Sideslip Angle ◽  
Shell Elements ◽  
Tire Force ◽  
New Type ◽  
Straight Ahead

Abstract This paper describes the application of a new type of non-linear 3D finite element tire model for simulating tire spindle force and moment response during side slip. The simulation model, briefly described in the paper, is composed of shell elements, which model the tread deformation, coupled to special purpose finite elements that model the deformation of the sidewall and contact between the tread and the ground. The sidewall special purpose element uses a pre-computed look-up table to efficiently calculate the sidewall shape and the forces acting on the tread. The model is designed to predict the forces at the spindle and ground and the overall tire shape, as opposed to the internal stress fields. This paper considers the following deformation scenarios: 1) a vertically loaded tire deforming laterally on a flat surface and 2) a tire rolling straight ahead under a prescribed sideslip angle. Experimental data is also presented to verify the force predictions.

Mesh Convergence Studies for Thin Shell Elements Developed by the ASME Task Group on Computational Modeling

2011 ◽  
Author(s):  
Gordon S. Bjorkman ◽  
David P. Molitoris
Keyword(s):  
Finite Element ◽  
Computational Modeling ◽  
Finite Element Model ◽  
Thin Shell ◽  
Element Model ◽  
Task Group ◽  
Plastic Strains ◽  
Shell Elements ◽  
Explicit Dynamics

The ASME Task Group on Computational Modeling for Explicit Dynamics was founded in August 2008 for the purpose of creating a quantitative guidance document for the development of finite element models used to analyze energy-limited events using explicit dynamics software. This document will be referenced in the ASME Code Section III, Division 3 and the next revision of NRC Regulatory Guide 7.6 as a means by which the quality of a finite element model may be judged. One portion of the document will be devoted to a series of element convergence studies that can aid designers in establishing the mesh refinement requirements necessary to achieve accurate results for a variety of different elements types in regions of high plastic strain. These convergence studies will also aid reviewers in evaluating the quality of a finite element model and the apparent accuracy of its results. In this paper the authors present the results of a convergence study for an impulsively loaded propped cantilever beam constructed of LS-DYNA thin shell elements using both reduced and full integration. Three loading levels are considered; the first maintains strains within the elastic range, the second induces moderate plastic strains, and the third produces large deformations and large plastic strains.

Sign in / Sign up

Export Citation Format

Share Document