Damping Characterization Using Hysteresis on Static Nonrolling and Dynamic Rolling Behavior of Farm Tires4

2008 ◽  
Vol 36 (2) ◽  
pp. 108-128
Author(s):  
G. Song ◽  
B. Conard ◽  
S. K. R. Iyengar
Keyword(s):  
Finite Element ◽  
Material Model ◽  
Element Model ◽  
Hysteretic Behavior ◽  
Vertical Acceleration ◽  
Hysteresis Model ◽  
Vertical Loading ◽  
Damping Behavior ◽  
Load Displacement ◽  
Vehicle Test

Abstract This paper presents the characterization of damping behavior as characterized by hysteresis for farm equipment tires and time domain numerical simulation of off-road tire rolling using finite element techniques. The hysteretic behavior is characterized by the load-displacement curves from static nonrolling vertical loading tests. Using a highly simplified finite element model based solely on tire catalog information and general constructional information, a hysteresis material model is used to simulate the hysteretic load-displacement behavior of farm tires. By choosing appropriate parameters for the hysteresis model, the static nonrolling finite element analyses results correlate very well to the experimental results. The fitted hysteresis material model is then used to simulate the dynamic rolling of a tire dropping off a curb. The bouncing vertical acceleration is of great interest to off-road tires. First, implicit dynamics is used to simulate the rolling using the calibrated hysteresis model. Very good correlations between the simulation results and vehicle test results are obtained. For better off-road rolling performance, the hysteresis model is recalibrated to reduce the vertical acceleration of the tire after the first bounce following the drop-off. The hysteresis model is replicated in explicit dynamics using an Abaqus/Explicit VUMAT subroutine to simulate the dynamic tire rolling behavior. By introducing additional damping and creep dissipation, the vertical acceleration is attenuated in excess of 50% after the first bounce following the drop-off to improve riding comfort. This hysteresis characterization has been shown to give good agreement with test data on nonrolling tests and dynamic drop-off tests. All modeling and solutions were performed using commercially available Abaqus software.

Delamination in the scoring and folding of paperboard

TAPPI Journal ◽  
2012 ◽  
Vol 11 (1) ◽  
pp. 61-66 ◽  
Author(s):  
DOEUNG D. CHOI ◽  
SERGIY A. LAVRYKOV ◽  
BANDARU V. RAMARAO
Keyword(s):  
Finite Element ◽  
Plane Deformation ◽  
Strain Analysis ◽  
Local Strain ◽  
Uniaxial Stress ◽  
Material Model ◽  
Element Model ◽  
Plastic Behavior ◽  
Stress Strain ◽  
Strain Fields

Delamination between layers occurs during the creasing and subsequent folding of paperboard. Delamination is necessary to provide some stiffness properties, but excessive or uncontrolled delamination can weaken the fold, and therefore needs to be controlled. An understanding of the mechanics of delamination is predicated upon the availability of reliable and properly calibrated simulation tools to predict experimental observations. This paper describes a finite element simulation of paper mechanics applied to the scoring and folding of multi-ply carton board. Our goal was to provide an understanding of the mechanics of these operations and the proper models of elastic and plastic behavior of the material that enable us to simulate the deformation and delamination behavior. Our material model accounted for plasticity and sheet anisotropy in the in-plane and z-direction (ZD) dimensions. We used different ZD stress-strain curves during loading and unloading. Material parameters for in-plane deformation were obtained by fitting uniaxial stress-strain data to Ramberg-Osgood plasticity models and the ZD deformation was modeled using a modified power law. Two-dimensional strain fields resulting from loading board typical of a scoring operation were calculated. The strain field was symmetric in the initial stages, but increasing deformation led to asymmetry and heterogeneity. These regions were precursors to delamination and failure. Delamination of the layers occurred in regions of significant shear strain and resulted primarily from the development of large plastic strains. The model predictions were confirmed by experimental observation of the local strain fields using visual microscopy and linear image strain analysis. The finite element model predicted sheet delamination matching the patterns and effects that were observed in experiments.

Dynamic Characteristic Analysis of Irregularity under Turnout by Vehicle-Turnout Rigid-Flexible Coupling Model

2014 ◽  
Vol 945-949 ◽  
pp. 591-595 ◽  
Author(s):  
Meng Chen ◽  
Yan Yun Luo ◽  
Bin Zhang
Keyword(s):  
Finite Element ◽  
Longitudinal Direction ◽  
Element Model ◽  
Vertical Displacement ◽  
Coupling Model ◽  
Interaction Force ◽  
Vertical Acceleration ◽  
Characteristic Analysis ◽  
Flexible Coupling ◽  
Multi Body

Finite element model of track in frog zone is built by vehicle-turnout system dynamics. Considering variation of rail section and elastic support, bending deformation of turnout sleeper, spacer block and sharing pad effects, the track integral rigidity distribution in longitudinal direction is calculated in the model. Vehicle-turnout rigid-flexible coupling model is built by finite element method (FEM), multi-body system (MBS) dynamics and Hertz contact theory. With the regularity solution that different stiffness is applied for rubber pad under sharing pad of different turnout sleeper zone, analysis the variation of vertical acceleration of bogie and wheelset, rail vertical displacement and wheel-rail interaction force, this paper proves that setting reasonable rubber pad stiffness is an efficient method to solve rigidity irregularity problem.

scholarly journals Response of the Flat Reinforced Concrete Floor Slab with Openings under Cyclic In-Plane Loading

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Eden Shukri Kalib ◽  
Yohannes Werkina Shewalul
Keyword(s):  
Finite Element ◽  
Reinforced Concrete ◽  
Lateral Displacement ◽  
Load Capacity ◽  
Element Model ◽  
Absorption Capacity ◽  
Hysteretic Behavior ◽  
Element Analysis ◽  
Floor Slab ◽  
Floor Slabs

The responses of flat reinforced concrete (RC) floor slabs with openings subjected to horizontal in-plane cyclic loads in addition to vertical service loads were investigated using nonlinear finite element analysis (FEA). A finite element model (FEM) was designed to perform a parametric analysis. The effects of opening sizes (7%, 14%, 25%, and 30% of the total area of the slab), opening shapes (elliptical, circular, L-shaped, T-shaped, cross, and rectangular), and location on the hysteretic behavior of the floor slab were considered. The research indicated that openings in RC floor slabs reduce the energy absorption capacity and stiffness of the floor slab. The inclusion of 30% opening on the floor slab causes a 68.5%, 47.3%, and 45.6% drop in lateral load capacity, stiffness, and lateral displacement, respectively, compared to the floor slab with no openings. The flat RC floor slab with a circular opening shape has increased efficiency. The placement of the openings is more desirable by positioning the openings at the intersection of two-column strips.

Substructure Coupling of a Machine Tool in Arbitrary Axis Positions Considering Local Linear Damping Models

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Thomas Semm ◽  
Michael B. Nierlich ◽  
Michael F. Zaeh
Keyword(s):  
Finite Element ◽  
Machine Tool ◽  
Dynamic Behavior ◽  
Element Model ◽  
Damping Behavior ◽  
Linear Damping ◽  
Virtual Prototypes ◽  
Damping Effects ◽  
Stiffness And Damping ◽  
Arbitrary Axis

Virtual prototypes, e.g., finite element models, are commonly used to reduce the development times of a new machine tool generation. However, the accuracy of these models is often limited by their representation of damping effects and the possibility to efficiently simulate the dynamic behavior in different axis positions. This paper shows the changing local damping distribution within a single-axis machine tool configuration for different axis positions. Based on this investigation, an approach to accurately model the position-dependent dynamics, while keeping the calculation times small, is presented. The virtual model of the machine is divided in several substructures, which consider the local damping behavior of each dissipation source. The reduced mass, stiffness, and damping matrices are coupled in the desired machine position by using multipoint constraints, which are generated at the desired machine position after the reduction of the substructures. Four different approaches to apply multipoint constraints on reduced substructures are compared, followed by an investigation of their influencing parameters. The most promising approach is compared with a model without local damping representation as well as a model without substructuring. By considering the local damping effects within the finite element model and coupling the reduced models of each component in arbitrary axis positions, an efficient analysis and optimization of the dynamic behavior of a machine tool over the whole workspace can be conducted.

A Virtual Model for Aluminum Hot Forging Using an Artificial Neural Network Material Model Within Finite Element Analysis

2005 ◽  
Author(s):  
B. Scott Kessler ◽  
A. Sherif El-Gizawy
Keyword(s):  
Finite Element ◽  
Effective Means ◽  
Hot Forging ◽  
Material Model ◽  
Element Model ◽  
Operating Conditions ◽  
Element Analysis ◽  
Preliminary Model ◽  
Wide Range ◽  
Artificial Neural

The accuracy of a finite element model for design and analysis of a metal forging operation is limited by the incorporated material model’s ability to predict deformation behavior over a wide range of operating conditions. Current rheological models prove deficient in several respects due to the difficulty in establishing complicated relations between many parameters. More recently, artificial neural networks (ANN) have been suggested as an effective means to overcome these difficulties. In the present work, a previously developed ANN with the ability to determine flow stresses based on strain, strain rate, and temperature is incorporated with finite element code. Utilizing this linked approach, a preliminary model for forging an aluminum wheel is developed. This novel method, along with a conventional approach, is then measured against the forging process as it is currently performed in actual production.

FE Modeling of the Three-Layer Human Carotid Artery Under Impact Loadings

2007 ◽  
Author(s):  
Aihong Zhao ◽  
Ken Digges ◽  
Mark Field ◽  
David Richens
Keyword(s):  
Finite Element ◽  
Carotid Artery ◽  
Model Simulation ◽  
Material Model ◽  
Element Model ◽  
Traumatic Rupture ◽  
Aortic Tissue ◽  
Fe Model ◽  
Arbitrary Lagrangian Eulerian ◽  
The Impact

Blunt traumatic rupture of the carotid artery is a rare but life threatening injury. The histology of the artery is key to understanding the aetiology of this injury. The carotid artery is composed of three layers known as the tunica intima, media, and adventitia, with distinct biomechanical properties. In order to examine the behaviour of the carotid artery under external load we have developed a three layer finite element model of this vessel. A rubber-like material model from LS-DYNA was selected for the FE model. The Arbitrary-Lagrangian Eulerian (ALE) approach was adopted to simulate the interaction between the fluid (blood) and the structure (carotid). To verify the FE model, the impact bending tests are simulated using this FE model. Simulation results agree with tests results well. Furthermore, the mechanical behaviour of carotid artery tissues under impact loading were revealed by the simulations. The results provide a basis for a more in-depth investigation of the carotid artery in vehicle crashes. In addition, it provides a basis for further work on aortic tissue finite element modeling.

Numerical analysis of energy absorption in expanded polystyrene foams

2019 ◽  
Vol 56 (4) ◽  
pp. 411-434
Author(s):  
Alejandro E Rodríguez-Sánchez ◽  
Héctor Plascencia-Mora ◽  
Elías R Ledesma-Orozco ◽  
Eduardo Aguilera-Gómez ◽  
Diego A Gómez-Márquez
Keyword(s):  
Finite Element ◽  
Stress Response ◽  
Finite Element Model ◽  
Energy Absorption ◽  
Material Model ◽  
Element Model ◽  
Expanded Polystyrene ◽  
Polystyrene Foam ◽  
Loading Rates ◽  
Expanded Polystyrene Foam

The expanded polystyrene foam is widely used as a protective material in engineering applications where energy absorption is critical for the reduction of harmful dynamic loads. However, to design reliable protective components, it is necessary to predict its nonlinear stress response with a good approximation, which makes it possible to know from the engineering design analysis the amount of energy that a product may absorb. In this work, the hyperfoam constitutive material model was used in a finite element model to approximate the mechanical response of an expanded polystyrene foam of three different densities. Additionally, an experimental procedure was performed to obtain the response of the material at three loading rates. The experimental results show that higher densities at high loading rates allow better energy absorption in the expanded polystyrene. As for the energy dissipation, high dissipation is obtained at higher densities at low loading rates. In the numerical results, the proposed finite element model presented a good performance since root mean square error values below 9% were obtained around the experimental compressive stress/strain curves for all tested material densities. Also, the prediction of energy absorption with the proposed model was around a maximum error of 5% regarding the experimental results. Therefore, the prediction of energy absorption and the compressive stress response of expanded polystyrene foams can be studied using the proposed finite element model in combination with the hyperfoam material model.

Finite Element Analysis on Behavior of the Joint with Steel Tube Confined Concrete (STCC) Column to Reinforced Concrete Beam

2011 ◽  
Vol 243-249 ◽  
pp. 527-530 ◽  
Author(s):  
Wen Da Wang ◽  
Zhi Feng Guo ◽  
Yan Li Shi
Keyword(s):  
Finite Element ◽  
Mechanical Performance ◽  
Material Model ◽  
Element Model ◽  
Reinforced Concrete Beam ◽  
Steel Tube ◽  
Confined Concrete ◽  
Composite Joints ◽  
Element Analysis ◽  
Composite Joint

The steel tube confined concrete (STCC) column exhibits excellent mechanical performance. A 3-D finite element model (FEM) using ABAQUS was established to simulate the performance of the composite joints with STCC column and RC beam. Accurate material model, rational element type, and solution method were discussed. Some STCC columns and composite joints with concrete-filled steel tubular (CFST) column and STCC column were modeled based on the model, respectively. The results from FEM are good agreement with the test results. The mechanism of the composite joint was investigated based on the FEM.

Rail Dynamic Vibration Absorber Design and Vibration Reduction Analysis

2011 ◽  
Vol 42 (11) ◽  
pp. 15-19
Author(s):  
Linya Liu ◽  
Bin Zhang ◽  
Jin Wang
Keyword(s):  
Finite Element ◽  
Degrees Of Freedom ◽  
Element Model ◽  
Vertical Displacement ◽  
Vibration Absorber ◽  
Vertical Acceleration ◽  
Dynamic Vibration Absorber ◽  
Finite Element Software ◽  
Dynamic Vibration ◽  
Damped System

The rail between two adjacent fasteners is regarded as the research object, and the rail is simplified as the main vibration system of undamped single degree of freedom, which supports the elastic components. The dynamic vibration absorber is simplified as a spring and damped system of 3-DOF(three degrees of freedom), to establish a mathematical model of rail dynamic vibration absorber. Through relevant theories, the parameter values of dynamic vibration absorber can be deduced when it achieves the best absorption effect. In accordance with the parameters, the scantlings of the structure of the dynamic vibration absorber can also be designed. Through the finite element software, the finite element model CRTS _ Ballastless Track system is established; with consideration of the value of irregularity, we load it variously. Analysis results showed that: compared to the rail and track where the dynamic vibration absorber is not installed, the maximum vertical displacement of the rail and track where a dynamic vibration absorber is installed was reduced by 65% and 67% respectively, the maximum vertical acceleration decreased by 75% and 70% and around, which reveals that the rail dynamic vibration absorber has a good vibration-reducing effect.

Sign in / Sign up

Export Citation Format

Share Document