Airbag Tire Modeling by the Explicit Finite Element Method

1997 ◽  
Vol 25 (4) ◽  
pp. 288-300 ◽  
Author(s):  
S. R. Wu ◽  
L. Gu ◽  
H. Chen
Keyword(s):  
Finite Element ◽  
Computational Procedure ◽  
Ford Motor Company ◽  
Feasibility Trial ◽  
Closed Volume ◽  
Finite Element Code ◽  
Explicit Finite Element ◽  
Shell Elements ◽  
Concept Model ◽  
Tire Modeling

Abstract An explicit finite element code FCRASH has been applied to both static and dynamic tire modeling. The computational procedure for predicting tire loads has been investigated. The typical tire model used in the simulation consists of a tire and rim. The tire is defined by membrane elements and the rim by rigid body with shell elements. The tire and rim form a closed volume. The airbag functionality in FCRASH, an explicit finite element code developed by Ford Motor Company, has been employed to simulate the test and to monitor the pressure and volume changes in the tire. Three static tire models (Taurus spare tire, P145/75R12, and P225/60R16) have been studied and the force-deflection curves are compared with test data. All of them exhibit a very good agreement. The standard spindle test for the P145/75R12 tire at three different speeds (10, 20, and 30 mph) is also simulated. The prediction of vertical and horizontal forces at 30 mph shows an excellent agreement with the test. The results for 20 and 10 mph are also reasonably good. The simulations for complex road conditions and full vehicle over bumps with a concept model are also performed as a feasibility trial. The CPU time used in both HP735 and CRAY computers for all these cases are comparable with other major CAE jobs. The experiments show that the explicit finite element code has a lot of advantages and strong potential to perform durability road load analysis with affordable computer costs.

Tire Modeling Methodology with the Explicit Finite Element Code LS-DYNA

2004 ◽  
Vol 32 (4) ◽  
pp. 236-261 ◽  
Author(s):  
W. Hall ◽  
J. T. Mottram ◽  
R. P. Jones
Keyword(s):  
Finite Element ◽  
Model Development ◽  
Transient Behavior ◽  
Finite Element Code ◽  
Explicit Finite Element ◽  
Modeling Methodology ◽  
Physical Testing ◽  
Tire Modeling ◽  
Tire Models ◽  
Constitutive Material

Abstract A finite element modeling methodology capable of predicting the transient behavior inside of a rolling car tire is presented. Although the approach has been specifically developed using the explicit finite element code LS-DYNA, it will be suitable for other commercial codes. Attention is given to the role played in the model development by the computational resource, the mesh requirements, the constitutive material relationships, and the contact and friction phenomena. Two different radial tire models are described based on analysis of an experimental car tire from Dunlop Tyres Ltd., UK. The first model was developed for static loading and its results are favorably compared with data determined by full-scale physical testing. The methodology is developed further in the second model so that a simulation can cope with the rolling situation. Measured stresses at the contact patch are used to show that the rolling tire model predicts the dynamic response with a reasonable degree of accuracy.

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.

Modeling the Dynamic Frictional Contact of Tires Using an Explicit Finite Element Code

2005 ◽  
Author(s):  
Tamer M. Wasfy ◽  
Michael J. Leamy
Keyword(s):  
Finite Element ◽  
Frictional Contact ◽  
Time Integration ◽  
Friction Model ◽  
Finite Element Code ◽  
Normal Contact ◽  
Explicit Finite Element ◽  
Beam Elements ◽  
Coulomb Friction Model ◽  
Stiffness And Damping

A time-accurate explicit time-integration finite element code is used to simulate the dynamic response of tires including tire/pavement and tire/rim frictional contact. Eight-node brick elements, which do not exhibit locking or spurious modes, are used to model the tire’s rubber. Those elements enable use of one element through the thickness for modeling the tire. The bead, tread and ply are modeled using truss or beam elements along the tire circumference and meridian directions with appropriate stiffness and damping properties. The tire wheel is modeled as a rigid cylinder. Normal contact between the tire and the wheel and between the tire and the pavement is modeled using the penalty technique. Friction is modeled using an asperity-based approximate Coulomb friction model.

Design and Control of Forming Processes Using Optimization Techniques

1999 ◽  
Author(s):  
O. Ghouati ◽  
H. Lenoir ◽  
J. C. Gelin ◽  
M. Baida
Keyword(s):  
Finite Element ◽  
Sheet Metal ◽  
Thickness Distribution ◽  
Optimization Technique ◽  
Optimization Techniques ◽  
Finite Element Code ◽  
Optimal Process ◽  
Shell Elements ◽  
Numerical Examples ◽  
And Control

Abstract The paper deals with the design and control of forming processes. The finite element code used is based on isoparametric shell elements with three or four nodes, the workpiece being considered as a sheet metal. An optimization technique is used in order to achieve the design or the control of the process by determining the optimal process parameters. The criterion used in that purpose can be based on thickness distribution as well as the respect of the final shape desired for the product. Numerical examples are presented as illustration.

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.

Study on the collapse of tapered tubes subjected to oblique loads

2008 ◽  
Vol 222 (11) ◽  
pp. 2025-2039 ◽  
Author(s):  
P Hosseini-Tehrani ◽  
S Pirmohammad ◽  
M Golmohammadi
Keyword(s):  
Finite Element ◽  
Cross Section ◽  
Numerical Models ◽  
Point Of View ◽  
Finite Element Code ◽  
Energy Absorber ◽  
Explicit Finite Element ◽  
Bending Deformation ◽  
Oblique Loading

In this work, several antisymmetric tapered tubes with an inner stiffener under axial and oblique loading are studied and optimum dimensions of the tapered tube are derived from a crashworthiness point of view. The importance of detecting these dimensions is optimizing the weight while the crashworthiness of tube is not damaged. By using an internal stiffener, crashworthiness is improved against oblique loads, and the sensitivity of tubes with respect to oblique loads and bending deformation is diminished. The numerical models have been developed using the explicit finite element code LS-DYNA. The crashworthiness of the optimized tapered tube is compared with that of an octagonal-cross-section tube which is known as the best energy absorber model in the literature. It is shown that an optimized tapered tube has an average of 29.3 per cent less crushing displacement in comparison with octagonal-section tube when both tubes have the same weights and the same peaks of crushing load. Finally, the orientation of loading is changed and the best orientation is proposed.

Finite element study into the effects of fiber orientations and stacking sequence on drilling induced delamination in CFRP/Al stack

2018 ◽  
Vol 25 (3) ◽  
pp. 555-563 ◽  
Author(s):  
Gong-Dong Wang ◽  
Stephen Kirwa Melly ◽  
S.K. Kafi Ahmed
Keyword(s):  
Finite Element ◽  
Composite Laminates ◽  
Research Work ◽  
Stacking Sequence ◽  
Finite Element Code ◽  
Model Surface ◽  
Shell Elements ◽  
Push Down ◽  
The Individual ◽  
Delamination Behavior

Abstract This research work has been aimed at understanding the effects of different fiber orientations and different stacking sequences of composite laminates on their damage during drilling of CFRP/Al stack. Finite element code Abaqus/CAE has been used for the implementation and analysis of the numerical model. Surface-based cohesive behavior available in Abaqus/CAE contact pairs has been used to simulate delamination behavior in the adhesive interfaces. In order to use the Hashin damage criterion (for intra-laminar damage) available in the finite element code, continuum shell elements have been used for laminates. Three stacking sequences each with 24 layers including [0°]24, [0°/90°]12s, and [−45°/90°4/45°2/−45°]3s have been considered for this study. The display group manager available in Abaqus/CAE visualization module enabled the individual access of the damage in each layer. Two layers both at drill entry and at CFRP/Al interface were used to study peel-up and push-down delamination, respectively. Sequence [0°]24 was found to have the largest damaged in both entry and interfaces, while sequence [−45°/90°4/45°2/−45°]3s was found to show better resistance to delamination damage.

Prediction of System Natural Frequencies Using an Explicit Finite Element Code With Application to Belt-Drives

2004 ◽  
Author(s):  
Tamer Wasfy ◽  
Michael Leamy ◽  
Rick J. Meckstroth
Keyword(s):  
Finite Element ◽  
Multibody Systems ◽  
Natural Frequencies ◽  
System Response ◽  
Finite Element Code ◽  
Frequency Range ◽  
Harmonic Force ◽  
Explicit Finite Element ◽  
Belt Drives ◽  
Time Histories

A time-accurate explicit finite element code is used to predict the natural frequencies of a typical class of flexible multibody systems — automotive accessory belt-drives. The system considered consists of a belt, two pulleys, and a tensioner. Two techniques are used to find the system natural frequencies: (a) applying a sharp impulse to the system and extracting the system natural frequencies from the resulting displacement/strain time-histories via an FFT; and (b) applying a harmonic force to the system and sweeping through a frequency range, while at the same time, monitoring for large system response. In the present paper a comparison between these two techniques is presented for a typical accessory drive. Also, recommendations are offered on how to best use each technique to efficiently extract the system’s natural frequencies.

Shell Elements Performance in Crashworthiness Analysis

2004 ◽  
Author(s):  
Shen Rong Wu ◽  
Nripen Saha ◽  
Ping Chen
Keyword(s):  
Finite Element ◽  
Lower Order ◽  
High Speed ◽  
Explicit Finite Element ◽  
Shell Elements ◽  
High Speed Impact ◽  
Finite Element Software ◽  
Refined Meshes ◽  
Triangular Elements ◽  
Crashworthiness Analysis

Crashworthiness analysis, a type of large deformation transient dynamics, has been an important and active area of researches and engineering applications. Several shell elements have been implemented in the finite element software for crashworthiness analysis. Among them, the 4-node quadrilateral Belytschko-Tsay element, using lower order integration technique is most commonly employed, due to its efficiency, robustness and overall accuracy. However, the lower order integration brings in some uncertainty. This paper is to conduct an engineering evaluation on performance of various shell elements, including Belytschko-Tsay, Belytschko-Leviathan (QPH), Bathe-Dvorkin, discrete Kirchhoff triangular elements, available in the commercial explicit finite element software. The study uses several linear and nonlinear benchmark examples and high-speed impact examples, to investigate the performance of these elements. Results of engineering interest and efficiency of computation are reported. Also, the behavior of finite element convergence, observed from the results by a sequence of refined meshes is investigated.

Sign in / Sign up

Export Citation Format

Share Document