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LS-DYNA

Explicit Finite Element Analysis

Crashworthiness · Occupant and Pedestrian Safety · Road Safety · Metal Forming · Impact · Drop Testing · Building Safety · Biomechanics

International LS-DYNA Alliance

A Network of LS-DYNA Software and Service Providers originated by CADFEM

www.LSDYNA-portal.com

INTERNATIONAL LS-DYNA ALLIANCE

International LS-DYNA Alliance

A Network of LS-DYNA Software and Service Providers originated by CADFEM

The International LS-DYNA Alliance is a network of LS-DYNA distributors and service providers from Europe, China, and Japan, originated by long-term German LSTC partner, CADFEM. The network partners collaborate closely and exchange knowledge and expertise, all partners ­ and consequently customers all over the world ­ can profit from the very special skills of all members. The International LS-DYNA Alliance currently has more than 40 experienced LS-DYNA engineers. The aim of the network is to provide customers with one contact facility for all LS-DYNA matters. Thus, the network acts as a virtual company and customers have access to the same know-how and the same people at all times, no matter in which country their development center is located. All members of the network are independent companies. However, close cooperation, exchange of knowledge, and tight, long-term professional and personal relationships between the members are a solid foundation to act as one virtual company whenever it is appropriate in benefit of a customer. Furthermore the customer is attended by a country fellowman sharing the same mentality, which is a very important characteristic of an efficient interaction between a customer and a supplier. HOW IT WORKS Example: Knowledge Transfer The Turkish Alliance member Figes was asked by a Turkish bus manufacturer to implement a complete LS-DYNA softand hardware environment including all pre- and postprocessing tools. Beside the implementation of the softand hardware a bus rollover homologation according to ECE R66 and the training of two engineers within a project-related rollover analysis was requested. A tight collaboration between the customer, Figes and CADFEM GmbH was the basis to fulfil all demands in the estimated period of time. SPECIAL LS-DYNA E X P E RT I S E O F C A D F E M A N D I N T E R N AT I O N A L LS-DYNA ALLIANCE · · · · · · · · · · · · · · Seat Design Composite Materials Crashworthiness Simulation Bus Rollover Train Crash Crash Performance of Aircraft and Train Seats Numerical Homologation for Commercial Vehicles Airbag Simulation Optimization Validated LSTC Dummies Metal Forming & Deep Drawing Civil Engineering Applications (Bridges, Buildings, etc.) Drop Tests for Nuclear Containers Specific Types of Explosion Simulations

L S - D Y N A S E RV I C E S B Y T H E I N T E R N AT I O N A L LS-DYNA ALLIANCE · · · · · Software Sales Basic & Advanced Training User Support Consulting Software Customization & Development

www.LSDYNA-portal.com

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INTERNATIONAL LS-DYNA ALLIANCE

PA RT N E R S I N E U R O P E

Austria CADFEM Austria GmbH www.cadfem.at Belgium Infinite Simulation Systems B.V. www.infinite.nl Czech Republic SVSFEM s.r.o. www.svsfem.cz Germany CADFEM GmbH www.cadfem.de

SWITZERLAND NETHERLANDS

RUSSIA

POLAND GERMANY

BELGIUM

LUXEMBOURG

CZECH REPUBLIC SLOVAKIAN REPUBLIC

AUSTRIA

SLOVENIA

HUNGARY

Greece PhilonNet Engineering Solutions www.philonnet.gr Hungary CADFEM Austria GmbH www.cadfem.at Italy Numerica s.r.l. www.numerica-srl.it Luxembourg Infinite Simulation Systems B.V. www.infinite.nl

ITALY

TURKEY

GREECE

PA RT N E R S I N C H I N A A N D J A PA N

The Netherlands Infinite Simulation Systems B.V. www.infinite.nl Poland MESco www.mesco.com.pl Russia CADFEM Representation Russia www.cadfem.ru Slovakian Republic SVSFEM s.r.o. www.svsfem.cz Slovenia CADFEM Austria GmbH www.cadfem.at Switzerland CADFEM AG www.cadfem.ch Turkey Figes CAD-CAE www.figes.com.tr China CCA Engineering Simulation Software, Ltd. Japan Cybernet Systems Co., Ltd www.cybernet.co.jp

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CONTENT

THE INTERNATIONAL LS-DYNA NETWORK

. . . . . . . . . . . . . . . . . page 1

LS-DYNA OVERVIEW

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 4

CRASHWORTHINESS SIMULATION . . . . . . . . . . . . . . . . . . . . . . . page 5

METAL FORMING SIMULATION . . . . . . . . . . . . . . . . . . . . . . . . . page 7

IMPACT SIMULATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . page 8

NON-STANDARD APPLICATIONS

. . . . . . . . . . . . . . . . . . . . . . . . page 9

LS-DYNA TECHNICAL OVERVIEW

. . . . . . . . . . . . . . . . . . . . . . page 10

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LS-DYNA OVERVIEW

LS-DYNA Overview

LS-DYNA is a multi-purpose, explicit and implicit finite element program used to analyze the nonlinear dynamic response of structures. Its fully automated contact analysis capability, a wide range of constitutive models to simulate a whole range of engineering materials (steels, composites, foams, concrete, etc.), error-checking features and the high scalability have enabled users worldwide to solve successfully many complex problems. LS-DYNA has many features to simulate the physical behavior of 2D and 3D structures: nonlinear dynamics, thermal, failure, contact, quasi-static, Eulerian, Arbitrary-Lagrangian-Eulerian (ALE), Fluid-Structure-Interaction (FSI), multi-physics coupling, etc.

www.lstc.com

Headquartered in Livermore, California, Livermore Software Technology Corporation (LSTC) develops LS-DYNA and a suite of related and supporting engineering software products. LSTC was founded in 1987 by John O. Hallquist to commercialize as LS-DYNA the public domain code that originated as DYNA3D. DYNA3D was originally developed at the Lawrence Livermore National Laboratory (LNLL), by LSTC's founder, Dr. John O. Hallquist.

separate processors and memories (MPP). The main advantage of MPP is the better performance in terms of CPU timing and scalability, when many CPU's are used. LS-DYNA's most prominent application areas are crashworthiness analysis and sheet metal forming analysis. Additionally LS-DYNA is extensively used to simulate impacts on structures from drop tests, underwater shock, explosions or high-velocity impacts. Explosive forming, process engineering, accident reconstruction, vehicle dynamics, thermal brake disc analysis or nuclear safety are further areas in the broad range of possible applications. In leading-edge research LS-DYNA is used to investigate the behaviour of materials like composites, ceramics, concrete, or wood. Moreover, it is used in biomechanics, human modelling, molecular structures, casting, forging, or virtual testing. The continual development of the implicit solver capabilities makes LS-DYNA an all-encompassing engineering tool for virtual product design and development.

LS-DYNA runs on a variety of platforms, including Intel based PC's (Windows, Linux), UNIX workstations, supercomputers, and massively parallel computers. The code is fully vectorized and takes advantage of multiple processors by shared-memory computing (SMP). In addition, domain decomposition is available. Parts of a job are distributed to several machines with

OVERVIEW OF LS-DYNA ANALYSIS CAPABILITIES · · · · · Nonlinear Dynamics Parallel Processing (SMP, MPP) Rigid Multi-Body Dynamics Quasi-Static Simulations Fluid Dynamics · Eulerian Capabilities · Arbitrary LagrangianEulerian (ALE) · · · · · · · · Fluid-Structure Interaction (FSI) Meshless Methods (EFG, SPH) Coupling to MADYM and CAL3D Underwater Shock Element-based Failure Analysis Design Optimization Structural-Thermal Coupling Adaptive Remeshing · Implicit Capabilities · Statics/Transient · Linear/Nonlinear · Eigenvalue Analysis · Automatic Implicit-Explicit Switching

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CRASHWORTHINESS SIMULATION

Crashworthiness Simulation

Automotive ° Truck/Bus ° Ship Building ° Aerospace ° Part Design

Requirements of the crashworthiness analysis have always been an integral part of the development of LS-DYNA. The powerful features of LS-DYNA helped manufacturers' natural desire to shorten vehicle design cycles and have significantly contributed to engineering modern vehicles, and improving their crashworthiness safety. At present, several crash cases must be investigated in order to develop a new design such as frontal impact with different off-set values, side impact of barriers at varying speeds, low speed collisions or the flip over of a car. Nowadays, highly detailed models with far more than one million of finite elements enable engineers to make extremely reliable predictions regarding the structural damage of a vehicle and danger to its occupants. The costs of simulation form only about 60% of the physical test. Costs can be as low as 10% for subsequent simulations. The time required for numerical simulation is only about 25% of that needed for physical testing procedures, a figure which drops to 6% for subsequent simulations. (Source: Dr.-Ing. h.c. F. Porsche AG, Entwicklungszentrum Weissach). The outstanding advantages of crash analysis, especially in terms of time and money savings, have also been acknowledged in other vehicle industries, including trucks, busses, ships, aircrafts and guided vehicles such as trains. Train, ship or aerospace crashworthiness assessments have specific, additional constraints compared to the automotive field. On the one hand, physical testing procedures are too expensive and make it possible to carry out only a very limited number of fullscale testings. On the other hand, it is difficult to obtain reliable results with small-scale tests. The sheer size of the structures involved, and the long duration of crash events, require finite element calculations of huge proportions. However, modern computers can handle large problems like this. LS-DYNA guarantees superior features in all these applications. Moreover, LS-DYNA is widely used by part manufacturers to reduce time-tomarket and costs for new products. This is typically done by reducing the traditional prototype- and test development cycle times. For instance, bumpers are designed with LS-DYNA to fulfill the specific regulations provided by the automotive industry. Examples include car body panels, steering columns, steering wheels, seats, airbag modules, bumper systems, car boots, cockpits, and tire design. Many tests in this area involve low speed impact. Quasi-static simulations, such as roof crushing, where buckling and post-buckling behavior of shell structures occurs, can be carried out in LS-DYNA. Moreover, it is advantageous that post-buckling loads of complex structures and contact problems with changing contact regimes involving friction can be dealt within LS-DYNA.

Calculation of the Collision and Grounding Behaviour of a double-hall Tanker

Courtesy LINDENAU GmbH, Schiffswerft & Maschinenfabrik, Germany

Swedish Cab Test

Courtesy MAN Nutzfahrzeuge AG, Germany

Front Crash Analysis

Bus Rollover Analysis

Courtesy TEMSA, A.S., Turkey

Developm Securest

Courtesy K Germany

Rinspeed Splash: Behaviour of Back Seat during Front Crash

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Engineered by ESORO, Switzerland www.esoro.ch

CRASHWORTHINESS SIMULATION

Occupant Safety ° Pedestrian Safety ° General Road Safety

Providing crash protection for the occupants of a vehicle is an integral part of development. Fully validated LS-DYNA finite element dummy models are available for most physical test devices. The range of frontal impact dummies includes Hybrid III 50th percentile male, 5th percentile female, 95th percentile male, 3 year old child and 6 year old child models. Free Motion Head form models for FMVSS 201 (Federal Motor Vehicle Safety Standard) vehicle interior head impact are also available. Current research also includes the development of an FE-model of a real human body to study the influence of crash impact on the occupants in even greater detail, e.g. to investigate the influence of a crash on passenger's internal organs. Biomechanics related structural and material models are thereby essential.

Huge efforts are undertaken to increase safety of other road users as well. The EEVC (European Enhanced Vehicle-safety Committee) is currently reviewing legislation for improving pedestrian safety in the case of direct impact with a vehicle. A full range of pedestrian impactor models, including head and leg shapes, has been modeled in LS-DYNA. This enables engineers to conduct research studies when designing e.g. the front-end structure of a vehicle. Studies using complete pedestrian dummy models can also be carried out for further research. Roadside safety features, such as guardrails and crash terminals, are designed to interact with all vehicle types in different ways. Simulationbased design is both efficient and cost effective in the prediction of vehicledevice interaction.

S P E C I A L C A PA B I L I T I E S F O R C R A S H W O RT H I N E S S S I M U L AT I O N · Seat Belts (Accelerometer, Pretensioner, Retractor, Sensor, Slip Ring) · Airbags (Elements, Materials, Inflating Models, Unfolded Reference Geometry, Sensor, Breakout, Bag-to-bag Venting, Leakage, Eulerian Deployment) · Dummies (Rigid and Deformable Hybrid III, Third-Party Dummies Available) · Coupling with Madymo

Airbag Deployment

Courtesy DYNARDO GmbH, Germany

Seat Development

Courtesy KEIPER GmbH & Co. KG, Germany

Evaluation of "Kaiser Bridge Railing System H2"

Courtesy KAISER Brückengeländer - Lärmschutz, Germany

ment of crash-active 2000 Headrest Pedestrian Safety: Male and Female Adults and Child Collision with Car Hood

Courtesy ihf Ingenieurbüro Huß & Feickert GbR mbH, Germany

EIPER GmbH & Co. KG,

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METAL FORMING SIMULATION

Metal Forming Simulation

Deep Drawing ° Rolling ° Forging ° Casting ° Multi Stage Processing ° Hydro Forming

Sheet metal component designers have turned to computer-based simulation in order to meet the demand for a quicker supply of better quality products. The goal is to produce tools which design the product "right first time". Simulation was initially used to "troubleshoot" a production problem but is now being utilized to design and test the tools before any metal is cast. LS-DYNA has been used for sheet metal stamping simulation since the late 1980s and is useful in assessing a proposed forming process and tool design. Assessment includes not only formability, e.g. cracking or wrinkling, but also quality in terms of impact line location, movement of features, springback, and surface conditions such as "teddy bear's ears". Complex forming sequences with multiple operations, including trimming, can be analyzed. Simulation allows the designer not only to confirm formability but also to optimize a given process, e.g. by examining different materials, blank shapes, tool loads, lubrication, draw beads, etc. Forming processes within the scope of a LS-DYNA simulation include rigid tool stretch and draw forming (with multiple tool action), sheet and tube hydro forming (including bending operations), flex forming, roll forming, and super-plastic forming. A LS-DYNA simulation can also be applied to bulk forming problems such as rolling, forging, and casting. Moreover, design results considering true thicknesses, initial stresses, and strains can be included in a structural analysis in order to assess the true response of the component. The software tool eta/DYNAFORM has been developed to provide a dedicated system for metal forming problems. This system provides comprehensive preprocessing (automeshing, tool positioning, draw bead representation) and postprocessing (animation, formability plot, forming limit diagram) features in one integrated package, making the application of forming simulation both fast and simple. S P E C I A L C A PA B I L I T I E S F O R S H E E T M E TA L F O R M I N G S I M U L AT I O N · Highly Accurate Material Models and Element Formulations · Rigid Tooling with Tool Movement Control · Adaptive Mesh Refinement with Look Ahead · Simplified Draw Bead Modeling · IGES/VDA Surface Contact · Multi-Stage Tooling · Hydro Forming, Hydro Mechanical Deep Drawing · Trimming · Implicit Springback · Thermal Coupling

Wire Grouting into a Clamp

Courtesy Robert Bosch GmbH, Germany

Sheet Hydroforming of Hood with segmented elastic Blank Holder

Courtesy IFU Stuttgart, Germany

Cracking and Wrinkling Results of Sheet Metal Forming Simulation matching with those of the physical Prototype

Courtesy ThyssenKrupp Umformtechnik GmbH Bielefeld, Germany

Forming Limiting Diagram (FLD)

Hydromechanical Deep Drawing of a stepped Cup

Courtesy IFU Stuttgart, Germany

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IMPACT SIMULATION

Impact Simulation

Drop Test ° Bird Strike ° Blade Containment ° Sloshing ° Building Safety

For many years, LS-DYNA has been used to simulate impact events of different containers. Sizes range from small shock absorber castings to heavy nuclear containers or spent fuel flasks. Cross-sections vary from impact of thin-gauge steel storage drums to thick-walled transport containers. Furthermore, drop test simulations are performed for consumer products, e.g. mobile phones, pagers, portable computers, coffee machines, and drilling machines. LS-DYNA assists in designing products so that certain components act as energy absorbers, in case of accidental damage. These damaged components can then be economically repaired or replaced. New features, such as Fluid-Structure Interaction (FSI) and Arbitrary Lagrangian-Eulerian (ALE), are used to investigate the impact of birds against turbine blades or windshields of aircrafts, or impact against a fuel-filled tank (tank sloshing). What these simulations have in common is that one part is highly deformed (bird, fuel) and can not be handled using the classical element formulations (Lagrangian Elements) without encountering problems in highly distorted elements. Therefore, Eulerian Element approaches are introduced as they are well-suited to finding a solution. Impact simulations are not only limited to consumer and industrial goods. High-risk buildings, such as nuclear plants, embankment dams or bridges are investigated with respect to impact, from aircrafts for example. Simulation can be of great help in these situations as it is impossible to carry out real tests.

Droptest Simulation of a Coffee Machine

Courtesy ihf Ingenieurbüro Huß & Feickert GbR mbH, Germany

Impact Simulations of a Mobile Phone: Drop Test and Ball Drop

Courtesy Motorola, Inc., Italy

Droptest Simulation of a technical Measurement Device

Courtesy Rohde & Schwarz GmbH & Co. KG, Germany

Head Injury Assessment due to an Impact on a stiffened Sheet Metal

Courtesy ZHW Zurich University of Applied Sciences, Winterthur, Switzerland

Development of an Impact Protection of a Cleaning Machine

Courtesy JohnsonDiversey, Switzerland

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NON-STANDARD APPLICATIONS

Non-Standard Applications

Earthquake ° Hydroplaning ° Avalanches ° Biomechanics ° Blast Loading

The scope of LS-DYNA is much broader than the "classical" applications, such as crashworthiness, metal forming, and impact simulation. Many other physical phenomena can be analyzed using LS-DYNA for dynamics and high nonlinearities. Different features available in LS-DYNA, like Fluid-Structure Interaction (FSI), Arbitrary Lagrangian-Eulerian (ALE), and Smooth Particle Hydrodynamics (SPH) enable the simulation of complex tasks such as hydroplaning or blast loading. Long term dynamics as required for earthquake simulations can also be performed. Buildings, bridges, and tunnels are just a few of the possible applications. In the biomechanic industry LS-DYNA is used to investigate the behaviour of artificial heart valves, or to model the complete human body, which can then be used in occupant safety analysis.

Response of a Tank Container to a lateral Blast

Courtesy TNO Defence, Security and Safety, The Netherlands

Hydroplaning Simulation

Courtesy of Marangoni SpA, Italy

Earthquake and Airplane Impact Simulation of a Nuclear Power Station

Courtesy DYNARDO GmbH, Germany

Blast Simulation of an explosive Material against a Metal Structure using advanced ALE and FSI Capabilities

Simulation of the Behaviour of a Container in a Water Basin

Courtesy Framatome ANP GmbH, Germany

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TECHNICAL OVERVIEW

Technical Overview

FUNCTIONALITY · Explicit Time Integration · Nonlinear Dynamics · Nonlinear Quasi-static · Implicit Analysis · Linear and Nonlinear Static · Transient Dynamic · Implicit Springback · Eigenvalue Analysis · Thermal Analysis · Steady State and Transient · Thermal-Mechanical Coupling · Fluid Analysis · Eulerian Capabilities · Arbitrary Lagrangian-Eulerian (ALE) · Fluid-Structure Interactions (FSI) · Meshfree Methods · Smooth Particle Hydrodynamics (SPH) · Element-Free Galerkin (EFG) · Adaptive Remeshing · Failure Analysis · Rigid Body Dynamics · Coupling to MADYMO, CAL3D · Underwater Shock Analysis (USA Coupling) · Design Optimization (LS-OPT) · Extensive Restart Capabilities · Parallelization and Vectorization · Fully Vectorized · Shared Memory Parallel (SMP) · Distributed Memory Parallel (MPP) · Keyword Input · User Programmable Features ELEMENTS · Shells and Membranes · Reduced Integrated for very Fast and Robust Simulations · Fully Integrated for most Detailed Investigations · Thin and Thick Shells · Composite Shell for Laminates and Sandwiches · Solids · Reduced Integrated for very Fast and Robust Simulations · Fully Integrated for most Detailed Investigations · Lagrangerian, Eulerian, ALE, and EFG · Linear Hexahedron, Quadratic Tetrahedron · 2-D Solids and Shells · Reduced Integrated for Fast and very Robust Simulations · Fully Integrated for most Detailed Investigations · Beams, Trusses, Cables · Arbitrary Cross Section Integration or Resultant Formulation · Discrete Elements · Springs/Dampers · Lumped Inertias · Seat Belts, Slip Rings, Retractors, Pretensioners · Weld Modelling · Mesh Independent Spotwelds with Failure · Fillet and Butt Welds with Failure M AT E R I A L S More than 150 Materials Models are available for · Metals with Plasticity and Damage · Plastics and Elastomers · Foams and Honeycombs · Fabrics · Glass · Composites · Geological · High Explosives and Propellants · Viscous Fluids · Biomechanical Tissues · User-defined Materials · Equation of States

C O N TA C T D E F I N I T I O N · Powerful, Efficient and Robust Contact Definitions · Penalty Formulation for Complex "over all" Contact · Constraint Formulation for most Accurate Solution · Flexible and Rigid Body in Arbitrary Combination · Edge-to-edge and Beam-to-beam Contact · Contact for Eroding Surfaces · Tied Surfaces with Failure · CAD and Analytical Surfaces · Rigid Walls and Rigid Road Surfaces · Friction Models (Velocity and Pressure Dependent, User-defined)

RIGID BODY DYNAMICS · Extensive Joint Definitions (Cylindrical, Planar, Cylindrical, Universal) · Implicit Multi-Body Dynamics · Deformable-to-Rigid Switching and vice versa

Impact Simulation of different Composite Crash Boxes

Courtesy Jacob Composite GmbH, Germany

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www.cadfem.de

DISTRIBUTORS

DEVELOPER

CADFEM GmbH Marktplatz 2 85567 Grafing b. München Germany Phone +49 (0) 80 92-70 05-0 Fax +49 (0) 80 92-70 05-77 E-Mail [email protected] Internet www.cadfem.de

LSTC Livermore Software Technology Corp. 7374 Las Positas Road Livermore, California 94550 USA Phone +1 (0) 925-4 49 25 00 E-Mail [email protected] Internet www.lstc.com

Since the founding days of the company in 1985, the CADFEM name has always stood for excellence in software solutions and customer services. The CADFEM expertise, long-standing experience, 90 highly motivated engineers, tight partnerships with major software makers, such as LSTC, ANSYS, or Moldflow, and connections to numerous research institutes take us one step ahead in a highly competitive market. The close cooperation between CADFEM and customers builds a solid foundation of efficient engineering.

Contacts of International LS-DYNA Alliance · Please see inside page 2 or visit www.LSDYNA-portal.com Contacts of LS-DYNA Distributors in other Countries · Please visit www.lstc.com

International LS-DYNA Alliance

A Network of LS-DYNA Software and Service Providers originated by CADFEM

www.LSDYNA-portal.com

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LS-DYNA2005.pdf

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