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7th International LS-DYNA Conference

Non-Penetrating Impact Simulation of Stitched Resin Film Infused Composites
A. M. Floyd, R. Vaziri, A. Poursartip - The University of British Columbia
The CODAM constitutive model has been implemented in LS-DYNA as a user-defined material model (UMAT). Using this material model, quasi-static over-height compact tension (OCT) tests on a stitched resin film infused (S/RFI) carbon/epoxy composite material were simulated, and the results demonstrated good agreement with the measured force and crack mouth opening displacement (CMOD). The same CODAM inputs were then used to simulate ...
Numerical Differences Observed Due to Different Binaries of LS-DYNA and Due to the Use of Various Compiler Options
Guangye Li, Wei David Chen, Jeff Zais - IBM
This paper compares the numerical results generated with different versions of LS-DYNA, including SMP versions ls950d, ls950e, ls960 (all with single precision), SMP version ls960 with double precision, and the MPI version mpp960. The car crash simulation model used in this study is the Neon model generated by the National Crash Analysis Center. The plotted results include internal energies, sliding interface energies, displacements, ...
Numerical Simulation of Light Armoured Vehicle Occupant Vulnerability to Anti-Vehicle Mine Blast
Kevin Williams - Defence R&D Canada - Valcartier
Francois Fillion-Gourdeau - Université Laval
An ongoing program at Defence R&D Canada to reduce the vulnerability of Light Armoured Vehicle (LAVs) to anti-vehicular blast mines is relying heavily on numerical simulation to help design and optimize add-on armour systems. One of the greatest challenges faced during the evaluation of the vulnerability of a given vehicle to blast mines is not only assessing the structural response of the vehicle but also evaluating the injuries sustained by ...
ON THE APPLICATION OF LS-OPT TO IDENTIFY NON-LINEAR MATERIAL MODELS IN LS-DYNA
David J. Benson,Morten R. Jensen - University of California, San Diego
Nielen Stander - Livermore Software Technology Corporation
Kenneth J. Craig - University of Pretoria
A response surface optimization algorithm for structural material or parameter identification is evaluated. The algorithm used is the Successive Response Surface Method (SRSM) available in LS-OPT. To illustrate the robustness of SRSM as a material identification tool, two test cases are presented. The first concerns the identification of the power-law material parameters of a simple tensile test specimen. The second test case involves the ...
Optimum Design of a Cellular Phone Using LS-OPT Considering the Phone Drop Tes
Jung Woo Kim - R & D Center
In-Yong Jo, Young-Gu Chung, Jae Moon Lim - KOSTECH Inc.
The main factor of the cellular phone fracture is the impact due to the phone drop. Two cases of design criteria are assigned to reduce the damage of the phone for the drop test. One is that the main part and the battery should not be separated, being dropped at a height of 30 cm. The other is that they should be separated, being dropped at a height of 150 cm. The separation between them could reduce the damage of the cellular phone. However, ...
Optimum Design of a Steel Bar Breaking System in a Sled Test Facility Using LS-OPT
In-Yong Jo, Young-Gu Chung, Hyung-Joo Lee, Jae Moon Lim - CAE Team, KOSTECH Inc.
The steel bar breaking system is a component of sled test system for the automobile crashworthiness. The purpose of this study is to optimize the steel bar breaking system in order to extract the crash pulse close to the barrier test result. The design variables are the height, the thickness and the number of each array of the steel bar plates. The optimum design is obtained using DOE (design of experiments) and RSM (response surface method) ...
PAB Deployment Simulation with Curved Retainer
Linhuo Shi - TG North America Corporation
Some passenger side airbags (PAB) are mounted on the cylindrical inflator directly through retainer with similar curvature of the inflator. To accurately simulate the deployment of such a PAB, a fine-tuned model using additional constraints in LS-DYNA are employed in this paper to simulate the curved mounted PAB. The results from the fine-tuned model are compared with the simulation results from the PAB models with simply fixed bag mouth. It ...
PARAMETRIC FINITE ELEMENT MODEL OF A SPORTS UTILITY VEHICLE - DEVELOPMENT AND VALIDATION
Gustavo A. Aramayo - Computation Materials Science Group
Matthew H. Koebbe - XYZ Scientific Applications, Inc.
As part of the NCAP (New Car Assessment Program) a finite element model of a Ford Explorer SUV has been developed using a formulation that results in a model with arbitrary element size and element size distribution. This correct Abstract. model enables the developer and analyst to choose a finite element model most applicable to the specific crash scenario under study. The element size and element distribution are parametrically defined at ...
PARAMETRIC STUDY ON IMPROVEMENT OF G4(1S) STRONG POST GUARDRAIL SYSTEM
Jin Wu, Ala Tabiei - Department of Aerospace Eng. & Eng. Mechanics
The G4(1S) strong post guardrail system is the most common guardrail system in the USA. Full- scale crash testing indicated that the vehicle rolled onto its impact side after exiting the guardrail system. This collision behavior of the roadside structure increases the occupant risk and is considered unsatisfactory for safety. Improvement of the G4(1S) guardrail system becomes an important issue concerned by the FHWA. The subject of this ...
Performance Analysis and Tuning of LS-DYNA* for Intel® Processor-Based Clusters
George Chaltas - Intel Corporation
W. R. Magro - Intel Americas
Using Intel software tools, including Intel® VTuneTM Performance Analyzer and Intel® Fortran Compiler, we analyze and tune the performance of MPP LS-DYNA* for clusters of Intel processors. We discuss the impact of various performance features of Intel processor-based systems, including vector/streaming instructions, on real LS- DYNA workloads. We compare single-precision performance and measure the impact of various cluster interconnect ...
Performance Evaluation on the ALE Formulation in MPP LS-DYNA
Yih-Yih Lin - Hewlett-Packard Company
The ALE fluid-structure coupling capability in LS-DYNA has become the main tool to accurately simulate the airbag-inflating process. However, it is very time-consuming: Running serially, it has been observed to take more than ten days on various computer platforms. Hoping to obtain speedup by parallelization, LSTC has been making efforts to implement the ALE formulation with MPP LS-DYNA. In this paper, the scalability of this implementation, ...
PROCESS PARAMETER SENSITIVITY STUDY ON TUBE HYDROFORMING
X.M. Chen - United States Steel Corporation
K. Palanisamy - ETA, Inc.
X.H. Zhu - Livermore Software Technology Corporation
Finite element analysis (FEA) has proven to be a useful tool for stamping process analyses. FEA has also been used increasingly for hydroforming analysis in the industry. In this paper, some examples for various hydroforming process simulations using LS-DYNA are presented. The effects of material characteristics and process parameters on tubular hydroforming are discussed. A sensitivity study has been conducted on a simple geometry. Three ...
Processing of Equality Constraints for Implicit in LS-DYNA v. 970
C. Cleve Ashcraft, Roger G. Grimes, Bradley N. Maker - Livermore Software Technology Corporation
LSTC is committed to building an implicit capability into LS-DYNA that is as capable as the flagship explicit capability. Over the years LSTC has added many different types of constraint handling capabilities in explicit that now have to be handled by implicit. The vast majority of these constraints are equality constraints imposed on the linear or nonlinear solution required at each time step. We will describe a new approach for handling ...
Quasi-Static Finite Element Analysis (FEA) of an Automobile Seat Latch Using LS-DYNA
Song Chen, Yuehui Zhu - Fisher Dynamics Engineering
In the present automotive industry, all suppliers and OEMs are focusing on designing, developing and manufacturing products and automobiles with higher quality, lower cost and faster delivery to the customers. The automobile industry has placed a significant amount of efforts including time and funding into developing products that can meet these challenges. This is probably one reason that in recent years Finite Element Analysis (FEA) has ...
Recent Developments in LS-DYNA for Civil Engineering
Brian Walker - ARUP
• LS-DYNA has well-known applications for earthquake and blast/impact engineering – Building design development – Site response studies – Development of isolators and energy absorbers • Arup have recently added new features: – Damping model for vibration studies – Material model - Rock and general Mohr-Coulomb – Staged construction – Pore water pressure analysis • This paper will show some applications of the new ...
Reduction in Time to Market of Automotive Seating System Using LS-DYNA
Hurshkumar G. Donde, Rakesh K. Lad, Prabal Kumar Biswas, Praveen B. Patil - Infosys Technologies Limited
Gordon Stace - Johnson Control Automotive UK Limited
The worldwide automotive industry is going through a sea change in order to get the share in the global market, which is becoming highly competitive & dynamic. The automotive OEM’s are faced with conflicting demands & challenges. There is an increasing demand for cost & weight reduction, fuel economy & reduction in time to market on one hand and on the other hand there is even more increasing demand towards assuring improved occupant ...
RESPONSE SURFACE AND SENSITIVITY-BASED OPTIMIZATION IN LS-OPT: A BENCHMARK STUDY
Nielen Stander - Livermore Software Technology Corporation
K.J. Craig - University of Pretoria
This paper evaluates the robustness of LS-OPT for response surface and design sensitivity-based optimization. The methodology uses linear response surfaces constructed in a subregion of the design space. These are constructed using either a design of experiments approach with a D-optimal experimental design or the available analytical or numerical gradient. The approach utilizes a domain reduction scheme to converge to an optimum. The scheme ...
SHAPE OPTIMIZATION OF CRASHWORTHY STRUCTURES
D. J. Eby, R. S. Sidhu - Applied Computational Design Associates, Inc.
R.C. Averill, E.D. Goodman - Department of Mechanical Engineering
Crashworthiness problems, which are highly dynamic and nonlinear, do not lend themselves well to classical gradient optimization techniques. Evolutionary-based design approaches that employ a form of guided stochastic search algorithm have been successfully applied to these problems. While many design optimization approaches are limited to a small number of continuous design variables, the approach described here can productively search ...
SHIP STRUCTURES SUBJECT TO HIGH EXPLOSIVE DETONATION
Mark Z. Vulitsky, Zvi H. Karni - John J. McMullen Associates
Predicting the structural response of a naval vessel to a high explosive detonation is an important requirement in naval shipbuilding. Unfortunately, current analysis methods do not provide high level of confidence leading to the utilization of large structural design safety factors. As a result, ships are heavier and more expensive to construct and maintain than may actually be required. Moreover, more reliable predictions can support ...
Simulation and Validation of FMVSS 207/210 Using LS-DYNA
Vikas Patwardhan, Tuhin Halder, Frank Xu, Babushankar Sambamoorthy - Lear Corporation
Federal Motor Vehicle Safety Standard 207 and 210 applies to automotive seats, their attachment assemblies, and seat belt anchorage assemblies. These regulations ensure their proper location for effective occupant restraint, and it also minimizes the possibility of anchorage failure due to the forces resulting from a vehicle crash. These requirements are the most critical in seat development process and are generally considered the ...
SIMULATION OF AIRBAG DEPLOYMENT USING A COUPLED FLUID-STRUCTURE APPROACH
Per-Olof Marklund - Linköping University
Larsgunnar Nilsson - Engineering Research Nordic AB and Linköping University,
This paper explores simulation techniques for airbag inflation using a coupled fluid-structure approach. The application is to be seen as an initial study on the phenomena occurring in an airbag during an Out of Position occupant impact. The application problem is an airbag that is set to impact a head form. The head form is positioned at a very short distance from the airbag. A Multi Material Arbitrary Lagrangian Eulerian technique in ...
Stochastic Analysis and Optimization of Full Vehicle System for Offset Crush
Hassan El-Hor, Nagappan Sekappan, Hamid Keshtkar - DaimlerChrysler Corporation
This paper attempts to account for the uncertainties inherited in the parameters involved in the offset crush of full vehicle system. The main objective of this work is to perform a reliability-based analysis to obtain the statistical characteristics of dash and toe intrusion responses in a 40 mph offset crush for a full vehicle system due to manufacture, material and design variability that will be defined in this study. Monte Carlo ...
Strain Rate Dependent Micro-Mechanical Composite Material Model for Finite Element Impact Simulation
Ala Tabiei, Weitao Yi - University of Cincinnati
Robert Goldberg - NASA Glenn Research Center
The present study aims at implementation of a strain rate dependent, non-linear, micro- mechanics material model for laminated, unidirectional polymer matrix composites into the explicit finite element code LSDYNA. The objective is to develop an accurate and simple micro- mechanical, rate dependent material model, which is computationally efficient. Within the model a representative volume cell is assumed. The stress-strain relation ...
STRUCTURAL OPTIMIZATION USING SPACE MAPPING AND SURROGATE MODELS
Marcus Redhe - Linköping University
Larsgunnar Nilsson - Engineering Research Nordic AB and Linkoping University
The aim of this paper is to determine if Space Mapping technique using Surrogate Models in combination with the Response Surfaces Methodology (RSM) is useful in optimization of crashworthiness applications. In addition, the efficiency of optimization using Space Mapping will be compared to conventional structural optimization using the Response Surface Methodology (RSM). To determine the response surfaces, several evaluations must be ...
Study on Optimal Design of Automotive Body Structure Crashworthiness
Wang Hailiang, Lin Zhongqin, Jin Xianlong - Shanghai Jiao Tong University
In this paper the optimal model of thin-walled sections of automotive body for structural crashworthiness is built. With computer design of experiment (DOE), the response surface model (RSM) of design can be obtained by carefully choosing a small quantity of samples in the design space. Pareto genetic algorithm (GA) is used in subsequently optimal design. With optimal design of thin-walled sections, the effects of the section parameters ...
The Future of CAE Software How to Achieve Process Automation
Brian Huf - Ford Motor Company
Achieving Process Automation is goal of all software – Automatically do what a user needs to get done. CAE software is no exception. In previous years, technological advances have driven most of the progress in CAE software. CAE software development is now starting to follow the lead of many other software companies by leveraging the concept of Process Guidance (a.k.a. Wizards). This approach has been found to be very effective as well being ...
USE OF MPP-DYNA FOR SIMULATING SHEET METAL FORMING PROCESSES
P. Christopher Galbraith, Dylan N. Thomas - Medusa Computing Corporation
Sheet forming simulations have been shown to have a profound impact on the tool and die industry, but accurate solutions for large panels often require large amounts of CPU time. The development of MPP-DYNA has allowed a large number of CPUs to be applied to a single problem thus reducing total elapsed time. This paper discusses the use of MPP-DYNA for obtaining accurate solutions in small amounts of elapsed time using inexpensive ...
USE OF STOCHASTIC ANALYSIS FOR FMVSS210 SIMULATION READINESS FOR CORRELATION TO HARDWARE TESTING
Amit Sharma, Ashok Deshpande, Raviraj Nayak - General Motors Corporation
The FMVSS210 regulation establishes requirements for seat belt assembly anchorage. The Federal government mandate requires use of Pelvic and Torso Body Blocks for testing belt anchor strengths for lap and shoulder belts respectively. The belt anchorages are to be designed to withstand loads of 13.34 kN if both lap and shoulder belts are used and 22.24 kN if only lap belts are used. The analytical simulation of the hardware test is done using ...
USGA Rule 4-1e Optimization of a Golf Driver Head Using LS-DYNA and Altair HyperStudy®
Tom Mase - Michigan State University
Eric Nelson, Jeff Brennan - Altair Engineering
Bruce Pettibone - Independent Consultant
A simulation of USGA’s test procedure for Rule 4-1e was optimized using 3 shape and 10 size design variables. The optimized solution increased the coefficient of restitution from 0.845 to 0.917 while maintaining stresses below 150 ksi and club head mass at 200 g.
Validation of a Loading Model for Simulating Blast Mine Effects on Armoured Vehicles
Kevin Williams, Robert Durocher, Benoit St-Jean, Jocelyn Tremblay - Defence R&D Canada - Valcartier
Scott McClennan - University of British Columbia
An ongoing program at Defence R&D Canada to reduce the vulnerability of Light Armoured Vehicle (LAVs) to anti-vehicular blast mines is relying heavily on LS-DYNA to help design and optimize add-on armour systems. A significant challenge in the numerical modelling work is the development of an accurate, or at least representative, loading history for the pressure and momentum transfer from the detonation of a buried blast mine. ...
Web-Centric LS-DYNA - Development of a Technical Computing Portal
Dan Fraser, Youn-Seo Roh, Henry H. Fong - Sun Microsystems, Inc.
The development of a Technical Computing Portal (TCP) for monitoring and managing of LS- DYNA runs is described. The Sun TCP is a new collaborative tool for High Performance and Technical Computing. It facilitates access, workload distribution, job monitoring, and management of LS-DYNA and other technical application jobs in a heterogeneous computing environment. It can be easily customized by LS-DYNA users, and by LSTC and its ...