10th European LS-DYNA Conference

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• A Fabric Material Model with Stress Map Functionality in LS-DYNA

  T. Borrvall (DYNAmore Nordic), C. Ehle, T. Stratton (Autoliv OTC)

  Material 34 (MAT_FABRIC) in LS-DYNA is the material model of choice for fabrics when simulating airbag deployment in the automotive industry. Over the years, the model has been subjected to continuous robustness improvements and incorporation of important application features and today it comes in several forms and with an extensive set of parameters. The state-of-the-art modelling approach is to use the FORM=14 option which allows for specifying uniaxial stress-strain curves in the fabric’s warp and weft directions.

• A Finite Element Investigation Into the Continuous Induction Welding of Dissimilar Material Joints

  M. Duhovic, J. Hausmann (Institut für Verbundwerk­stoffe), P. L´Eplattenier, I. Caldichoury (LSTC)

  Continuous induction welding is an advanced material processing method with a very high potential of providing a flexible, fast and energy efficient means of joining together thermoplastic composites to themselves and metals and alloys. However, selection of the processing parameters and optimization of the process is very difficult as it involves the interaction of up to four differen t types of physics. In addition, many different material combinations including materials with low or high electrical conductivity, thermal conductivity and heat capacity, make the intuitive selection of processing parameters impossible. In this work, a si mulation test - bed, setup for the continuous induction welding of two material partners and their corresponding physics interactions is used to investigate the induction welding possibilities for several combinations of hybrid material joints.

• A Graphical User Interface for Simulating Resin-Transfer-Molding Combining LS-DYNA and OpenFOAM

  M. Wagner, M. Martins-Wagner (OTH Regensburg), A. Haufe, C. Liebold (DYNAmore)

  The paper describes parts of the joint research project Swim-RTM including several industrial and academic partners. Its goal is to combine LS-DYNA and the open-source fluid-dynamics solver OpenFOAM® to simulate the production process for fiber reinforced plastics, particularly the resin-transfer-molding (RTM) process. In this process, the layers of dry fabric (uni-directional or woven) are formed in the mold (draping) and then filled with liquid resin with high pressure at injection points.

• A New Feature to Model Shell-Like Structures with Stacked Elements

  T. Erhart (DYNAmore)

  A computational method for the numerical simulation of stacked shell-like structures will be presented. These types of plane load-bearing components possess a thickness which is small compared to its other (in-plane) dimensions and physical properties vary in thickness direction in distinct layers. Such materials are made from two or more constituent materials with different physical or chemical properties, that when combined, produce a material with characteristics different from the individual components. The individual components remain separate and distinct within the finished structure.

• A Numerical Investigation of Turbulent Flow in Circular U-Bend

  A. Miloud, M. Aounallah, O. Imine, M. Guen (University of Science and Technology of Oran Algeria)

  A numerical investigation of Turbulent flows through a circular 180° curved bend with defined as the bend mean radius to pipe diameter for a Reynolds number of 4.45×104 is presented in this study . The computation domain is performed for a U-Bend with full long pipes at the entrance and at the exit. Two turbulence models were tested in this work.

• A Variable Finite Element Model of the Overall Human Masticatory System for Evaluation of Stress Distributions During Biting and Bruxism

  S. Martinez, J. Lenz, Prof. K. Schweizer­hof (Karlsruhe Institute of Technology), H. Schindler (University of Heidelberg)

  Simulating the masticatory system during chewing, clenching and bruxism, requires the model to capture the dynamical behavior of its different components: the mandibula and maxilla, the temporomandibular joint (TMJ) including the articular disc and the surrounding cartilage layers, the teeth, the periodontal ligaments (PDL), and the muscles

• A Weight Balanced Multi-Objective Topology Optimization for Automotive Development

  N. Aulig, S. Menzel (Honda Research Institute Europe), E. Nutwell (Ohio State Uiversity), D. Detwiler (Honda R&D)

• ACP Process Integrated 3B Forming Optimization

  A. Farahani, D. Mittal (Engineering Technology Associates), J. Shaw (US Steel)

  The automotive and steel industries have several initiatives such as the development of 3 rd Generation Advanced High Strength Steels (AHSS), the Nonlinear Strain Path Project and the A/SP AHSS Stamping Team Projects. These initiatives are efforts to expand the forming design space with AHSS to enable increased part complexity, which will allow AHSS to be incorporated into more vehicle components and enable mass reduction. The proposed approach discussed in this presentation will provide a new tool in the effort to expand the forming design space of AHSS.

• ACP_Forming_Brochure.pdf
• ACP_Natures_Way.pdf
• ACP_Process_Brochure.pdf
• Agenda.pdf
• Agile Dummy Model Development Illustrated by Refinement Activities of the WorldSID Shoulder Model

  R. Brown, G. Stokes (Jaguar Land Rover), U. Franz, S. Stahlschmidt (DYNAmore)

  The Agile Software Development is a method that promotes adaptive planning, evolutionary development, early delivery, continuous improvement, and encourages rapid and flexible response to changes. This method is established in the development of software and influences also many other development processes. The employees at DYNAmore are developing dummy models together with a consortium of car companies since decades. The models are used world wide by almost all automotive companies that run LS-DYNA to design their restraint systems.

• ALE/FSI AirBlast Modeling: On the Way to One Billion Elements

  The Arbitrarian Lagrangian Eulerian (ALE) method of LS-DYNA® software is the best actual solution to perform AirBlast simulation. Indeed, thanks to its coupling method (ALE/FSI), it allows to the user to model complex blast waves interaction with Lagrangian structures. Today, due to hardware advances (the computer power highly increased) and LS-DYNA technology enhancement (ALE Mapping, MPP), it becomes possible to consider models with a very large volume of air, while keeping a good accuracy with a small element size. These new possibilities lead to a quantity of elements never reached before, for which LS-DYNA and LS-PrePost® had to adapt. In this paper, based on work realized with the help of LSTC, we will explain what exactly are the issues of modeling an ALE/FSI model with more than 100 million elements and what solutions were found. We will present some facilities to pre-process such a big model, like the new LS-PrePost “Long Format” or an innovative way to create ALE mesh using a new LS-DYNA keyword. We will also discuss about other important points concerning MPP decomposition, memory needs and post- processing, in order to give LS-DYNA users a complete overview of the ins and outs.

• An Advanced Identification Procedure for Material Model Parameters based on Image Analysis

  L. Peroni, M. Scapin, C. Fichera (Politecnico di Torino)

  Inverse methods for the material strength model calibration are widespread techniques, which allow taking into account for the actual strain, strain-rate, temperature and triaxiality fields inside the specimen. An optimization procedure generally starts from experimental measurement of force-stroke time history and is based on the minimization of the difference between experimental and numerically computed quantities. In this work, the strength model identification is performed also on the basis of the specimen shape recorded during the test. This information is imposed as boundary condition, which forces the experimental profile to the external surface of the specimen.

• An Assessment of ALE Mapping Technique for Buried Charge Simulations

  I. Kurtoğlu (FNSS Savunma Sistemleri)

  In this work, the effects of ALE mapping technique developed by LSTC [1] are investigated for buried charge simulations. Before mapping studies, a mesh sensitivity study is performed for the pure ALE simulations to investigate the effect of 3D mesh size on the impulse. The ALE mapping is performed from a 2D axisymmetric model to full 3D model.

• An Investigation of AL7075-T651 Plate Perforation Using Different Projectile Nose Shapes

  B. Balaban, İ. Kurtoğlu (FNSS Savunma Sistemleri)

  In this study, the ballistic resistance of monolithic and double-layered plates made of AL7075-T651 are evaluated using the non-linear finite element code LS-DYNA®. Plate simulations are carried out using 20 mm diameter, 197g mass hardened steel projectiles with blunt and ogival nose shapes. Penetration simulations of 20 mm monolithic plates made of AL7075-T651 are performed with both Lagrange and ALE methods and the results are compared with literature experimental studies.

• An Investigation of Modeling Approaches for Material Instability of Aluminum Sheet Metal using the GISSMO Model

  G. Falkinger (Leichtmetallkompetenz­zentrum Ranshofen LKR), P. Simon (AMAG Rolling)

  The most generally accepted tool for the assessment of formability of sheet material up to the present date is the forming limit diagram (FLD). It allows the identification of critical areas in a sheet - forming simulation where critical thinning or the appearance of cracks is to be expected. The FLD is determined experimentally in Nakajima tests and is widely used in the design of sheet forming processes . However it is known that the assessment based on the FLD is incomplete.

• Analysis of Unsteady Aerodynamics of a Car Model with Radiator in Dyna­­mic Pitching Motion using LS-DYNA

  Y. Nakae, J. Takamitsu, H. Tanaka, T. Yasuki (Toyota Motor)

  This paper describes the numerical analysis of unsteady aerodynamics of a radiator mounted car model in dynamic pitching motion using LS-DYNA ICFD solver. Large-Eddy simulations with ALE method and porous media modeling were performed to clarify the unsteady aerodynamic forces acting on cars with engine compartment in dynamic motion.

• Application of the SPH Finite Element Method to Evaluate Pipeline Response to Slope Instability and Landslides

  A. Fredj, A. Dinovitzer (BMT Fleet Tech-nology), M. Sen (Enbridge Pipelines)

  Buried pipelines operating on active slopes can be subject to lateral and axial loads resulting from slope instability and landslides. The techniques to predict pipeline displacements, loads, stress or strains are not well described in design standards or codes of practice. Finite element analysis based soil-pipe interaction simulation has developed in recent years and is proving to be a useful tool in evaluating the pipeline behavior in response to slope movement. A description of the BMT pipe soil interaction modeling techniques, their validation against full scale trails and comparison to spring support models has been previously published.

• Assessment of Motorcycle Helmet Chin Bar Design Criteria with Respect to Basilar Skull Fracture using FEM

  S. Farajzadeh Khosroshahi, M. Ghajari (Imperial College London), U. Galvanetto (University of Padova)

  Statistical studies showed that the chin bar of full-face helmets is the region with the highest number of impacts. In an Australian research, fifty percent of severe impacts took place to the front of the helmet and forty percent of these resulted in Basilar Skull Fracture (BSF). There are two standards, which include criteria for assessing the performance of the helmet’s chin bar, Snell M2015 and ECE 22.05.

• Book of Abstracts.pdf
• CAE Analysis of Passenger Airbag Bursting through Instrumental Panel Based on Corpuscular Particle Method

  Y. Feng, M. Beadle (Jaguar Land Rover)

  The safety regulation requires that passenger airbag (PAB) to deploy into working position in time without causing any fragmentation of its surrounding structure. Due to the significant load of airbag deployment and its complex unfolding process, it is always a challenge to design a PAB system which enables airbag safely bursting through instrumental panel. A CAE based approach has been developed at Jaguar Land Rover (JLR) to lead the passenger airbag system design. The foundation of the CAE approach is to model the airbag bursting loading condition representatively.

• CAE as a Service as Cloud Platform for the Full LS-DYNA Simulation Process

  A. Geiger, K.-H. Hierholz, C. Neimöck (T-Systems)

  Mit CAE as a Service stellt T-Systems eine Cloud-basierte Lösung für den gesamten CAE Prozess vom Infrastruktur- bis zum Softwarelayer mit dynamisch skalierbarem Durchsatz und Leistungsfähigkeit. Use cases sind u.a. (a) HPC Spitzenlastabdeckung für Durchsatz- und Problemgrößen-Peaks, (b) Bereitstellung des vollständigen CAE Prozesses mit Pre-/Solver-/Postprocessing und Simulation Data Management als Service, (c) Bereitstellung von sicheren und skalierbaren Kollaborationsumgebungen für die gemeinsame Entwicklungsarbeit zwischen OEM und OES.

• CAE Validation Study of a Side Window Impact using Plexiglas Materials

  D. Lopez Ruiz (Tecosim Technische Simulation), A. Rühl, Prof. S. Kolling (THM Giessen), E. Ruban, B. Kiese­wetter, S. Ulzheimer (Evonik Industries)

  An experimental and numerical study regarding the head impact on a side rear window was performed. Based on several years of material development and manufacturability (Evonik Industries AG), the expert knowhow in material testing and LS-DYNA material implementation (Giessen Institute of Mechanics and Materials) and the CAE user experience (TECOSIM Technische Simulation GmbH) and in closer cooperation between all parties, it was decided to start a development study. The outcome of the study should show the behavior of different PLEXIGLAS® (PMMA) windows using different PLEXIGLAS® grades and possible feasible combinations.

• Calculation and Validation of Material Tests with Specimens Made out of Filled Elastomers

  P. Thumann, K. Swidergal, Prof. M. Wagner (OTH Regensburg)

  In deep-drawing dies for steel sheet parts of car bodies huge masses are moved. To prevent vibrations, which occur by sudden acceleration or stopping of those masses, elastomeric tubular dampers [1] are used. The dampers are made out of carbon filled elastomers. A good knowledge about the material behaviour of metals is available.

• Characterizing LS-DYNA Performance on SGI Systems using SGI MPInside MPI Profiling Tool

  T. DeVarco, O. Schreiber, A. Altman, S. Shaw (Silicon Graphics)

  SGI delivers a unified compute, storage and remote visualization solution to manufacturing customers reducing overall system management requirements and costs. LS-DYNA integrates several solvers into a single code base. In this paper, the explicit solver is hereby studied for better matching with the multiple computer architectures available from SGI, namely, multi-node Distributed Memory Processor clusters and Shared Memory Processor servers, both of which are capable of running in Shared Memory Parallelism (SMP), Distributed Memory Parallelism (DMP) and their combination (Hybrid) mode. The MPI analysis tool used is SGI MPInside.

• Chemically Reactive Flows in Airbag Inflator Chambers

  Chemically Reactive Flows in Airbag Inflator Chambers, K. Im, G. Cook Jr., Z. Zhang (LSTC)

  Airbags are part of an important vehicle safety system, and the inflator is an essential part that generates a specific volume of gas to the airbag for a short duration of time. Recently, we have developed numerical models of automotive airbag inflators in conjunction with the LS-DYNA® chemistry solver. In this study, detailed and comprehensive descriptions for theoretical models are developed for a conventional pyrotechnic inflator (PI) and a compressed, heated gas inflator (HGI).

• Classification-based Optimization and Reliability Assessment using LS-OPT

  A. Basudhar, I. Gandikota, N. Stander (LSTC), A. Svedin, C. Belestam (DYNAmore Nordic), K. Witowski (DYNAmore)

  Simulation-based design often involves the use of metamodeling techniques that provide a cheap surrogate model to replace expensive evaluations. Several types of metamodels are available in LS-OPT, e.g. Radial Basis Function Networks, Feed Forward Neural Networks, Kriging etc.

• Cloud-Enabled CAE Solutions: Requirements, Basic Concepts and Usability

  A. Heine (CPU 24/7)

  Up-to-date, particularly commercial methods of numerical simulation are able to meet requirements of modern product development and optimisation processes. However, essential prerequisite is not only the application software but also the appropriate High Performance Computing (HPC) resources. Specific applications, like simulation of large models with a very high number of grid points, CFD-driven design optimisation with necessary innumerable variations as well as complex, multidisciplinary problems regarding the simulation of iterative interactive effects are typical examples of getting efficient, high-quality, prompt and precise results only through appropriate High Performance Computing.

• Cohesive Contact Modeling in Thermoforming Simulations of Metal-CRFP-Metal Sandwich Sheets

  Ö. Cebeci, A. Zeiser (Inpro Innovations­gesellschaft für fortgeschrittene Produk­tionssysteme in der Fahrzeug­industrie), M. von Scheven (University of Stuttgart)

  A novel carbon fiber reinforced metal laminate based on thermoplastic polymer is investigated in the project LEIKA. For the safeguarding of the production of the parts made of this material, coupled thermo-mechanical simulations have to be carried out. Experiments show a large relative sliding, separation and re-sticking behavior between layers during the forming of the heated sheets. Hence, each layer of the laminate needs to be modeled as an individual shell in order to represent the different forming behavior.

• Collaboration for Future HPC-based Simulation Technologies

  A. Walser (Automotive Simulation Center Stuttgart)

  The use of Numerical Simulation and High Performance Computing (HPC) in vehicle development has already been established for years. Nowadays it is the third pillar of vehicle development along with construction and testing. Computer Aided Engineering (CAE) methods in combination with HPC technologies enable engineers to solve complex problems in a quick and cost-effective way long before hardware prototypes are available. Furthermore it opens up the possibility to analyze not just a single concept idea, but many concept variations parallel.

• Comparison of Crash Models for Ductile Plastics

  B. Croop, M. Lobdell, H. Lobo (DatapointLabs)

  There is interest in quantifying the value of different material models being used in LS-DYNA today for the modeling of plastics. In our study, we characterize two ductile, yet different materials, ABS and polypropylene, for rate-dependent tensile properties, and we use the data to develop material parameters for the material models commonly used for plastics: MAT_024 and its variants, MAT_089 and MAT_181. We then perform a falling dart impact test, which produces a complex multi-axial stress state, and we simulate this experiment using LS-DYNA. For each material model, we are able to compare simulation to actual experiment, thereby obtaining a measure of fidelity of the simulation to reality. In this way, we can assess the benefits of using a particular material model for plastics simulation.

• Comprehensive Correlation of Seat Track Assembly – From Forming to Assembly Test

  S. Sinne, H. Klose, V. J. Dura Brisa, P. Partheymüller (Brose Fahrzeugteile)

  The dimensioning of seat structure including its adjusting components is always a challenge between comfort, lightweight and strength. The main interface between seat structure and vehicle is the s eat track assembly . It enables the length adjustment and transfers a significant amount of the crash load. The increased demands to lightweight , reduction of development time and cost efficiency require a continuous improvement of simulation models regarding accuracy in p redictability.

• Cost-Effective Sizing of Your HPC Cluster for CAE Simulations

  N. Henkel, S. Treiber (GNS Systems)

  The use of CAE techniques as an integral part of product development has become indispensable in the automotive industry. The investigation of different problems with the help of virtual simulation is used daily by development teams. They need considerable computing power, which is provided by HPC (High Performance Computing) clusters. Typical cluster installations in the automotive industry can range from local resources with 50 to 200 cores up to centralized cloud computing installations with more than 10,000 cores.

• Crashworthy Design of Composite Structures Using CAE Process Chain

  M. Chatiri (Cadfem), T. Schütz (Adam Opel), Prof. A. Matzenmiller (University of Kassel)

  The materials used in automotive industry should play key role in overcoming the current challenging demands such as increased global competition, need for vehicles with highest efficiency, reduction in costs, stringent environmental and safety requirements. This eventual usage of lighter materials mean lighter vehicles and low greenhouse gas emissions. Composites are getting more recognition and hence being used increasingly in the automotive industry due to their excellent weight specific characteristics such as strength and stiffness.

• Creation and Validation of Material Cards for Aluminium Sheet Metal Materials

  R. Hennig (Aleris Rolled Products Germany)

  While many simulation programs contain sufficient material cards for most of the steel materials, the aluminum cards often aren’t available yet. Therefore many of the aluminum processing suppliers have to create their own cards but aren’t willing to change them with other suppliers or customers because of the necessary high effort to get them. This leads to a higher uncertainty of the ability to process aluminum sheet metal materials in the automotive industry especially for small and medium-sized enterprises which aren’t able to create their own cards and simulate their forming processes with sufficient reliability and prevents a higher distribution of aluminum sheets in the market in general. Therefore Aleris - one of the leading Aluminum Suppliers in the world - has decided to create their own material cards for all of their sheet materials to help their customers to simulate their forming processes with the Aleris aluminum sheets with ease and reliability.

• Current Status of LS-PrePost and the New Features in Version 4.2

  P. Ho (LSTC)

  LS-PrePost is an advance pre and post-processor that is delivered free of charge with LS-DYNA. It is designed and developed specially to support LS-DYNA in pre-processing and post-processing all in one single code. The main features in the pre-processing include CAD geometry creation and manipulation. A wide range of meshing capabilities including automatic mesh generation for surfaces, hexahedron and tetrahedron elements generation for solid

• Damage in Rubber-Toughened Polymers – Modeling and Experiments

  M. Helbig DYNAmore), T. Seelig (Karlsruhe Institute of Technology)

  The superior ductility and toughness of rubber-toughened polymers relies on microscale deformation and damage mechanisms such as void growth, shear yielding and crazing. In the present work, a micromechanical model for the inelastic deformation behavior of rubber toughened polymers is developed which focuses on the effect of crazing, i.e. the formation of localized cohesive zones of fibrillated material.

• Damping Modeling in Woven Lattice Materials

  S. Szyniszewski (University of Surrey), S. Ryan, S. Ha, Y. Zhang, T. Weihs, K. Hemker, J.K. Guest (The Johns Hopkins University Baltimore)

  Woven lattice materials were modelled to develop thin sheet dampers for attenuation of vibrations in high temperature environments. 3-D weaving has enabled manufacturing of woven lattice materials from metallic fibers that are suitable for high temperature applications. Such materials offer promising dynamic characteristic such as high vibration damping that can be combined with cooling and adequate stiffness. Dynamic tests of NiCr woven samples were simulated using LS-DYNA software in order to examine the energy dissipation mechanisms.

• Development of a Fully-Tabulated, Anisotropic and Asymmetric Material Model for LS-DYNA (*MAT_264)

  S. Haight, C.-D. Kan (George Mason University), P. Du Bois (Consultant)

  The purpose of this research is to develop a fully-tabulated, anisotropic, asymmetric and rate dependent material model for solid elements. Physical tests of several metallic materials have shown to have anisotropic (or orthotropic) characteristics. While many material models in LS-DYNA currently have anisotropic modeling options, they are typically focused on the material forming applications – not crash and impact analysis. Unlike most anisotropic forming material models, this model will have: rate dependency, temperature dependency, tabulated hardening (as opposed to parameterized inputs), associated flow, directional tensile compressive asymmetry and the ability to maintain stability for large deformations.

• Development of a Tool for Automatic Calibration of Material Models in LS-DYNA

  A. Mardalizad ( Polytechnic University of Turin), E. Sadeghipour, M. Lienkamp (Technical University Munich)

  LS-DYNA offers a wide variation of material cards to cover different needs in diverse applications. However, choosing the most proper material model among 250 keywords can be quite deceptive. Therefore, an algorithm has been developed to suggest proper material keywords depending on users’ applications. The algorithm is also coupled with a database of material models to look for proper material cards among the existing ones

• Development of an Anisotropic Material Model for the Simulation of Extruded Aluminum under Transient Dynamic Loads

  A. Smith (Honda R&D Americas), P. Du Bois (Consultant), T. Borrvall (DYNAmore Nordic)

  The movement towards lightweight mate rials in the construction of automotive bodies is leading to an increase in parts made from extruded aluminum and other materials with a large degree of anisotropic behavior. The need to model these anisotropic properties and predict the behavior of these materials is increasing rapidly. A review of the anisotropic material models available in LS - Dyna including Material types 36, 133, 135, and 243 led to the decision that Material type 36 with option “Hardening Rule 7“ (HR7) was the most appropriate choice for application towards analysis of extruded aluminum parts under both static and dynamic loads. Material type 36 ( *MAT_3 - Parameter_Barlat ) has a history of use in forming applications and shows promise as a valuable tool for modeling anisotropic behavior in high strain, high velocity simulation applications as well.

• Developments in LS-DYNA for Metal Forming Simulations

  X. Zhu, L. Zhang (LSTC)

  One - step simulation with keyword *CONTROL_FORMING_ONESTEP has been widely in use in crash and safety for forming stress and strain initialization. It has also being used for initial estimating of blank size in stamping application. One problem stamping users face is the position of the blank after unfolding can be undesirable. Also, the shifted unfolded blank is not easy to align relative to the tooling position.

• Digimat Material Model for Short Fiber Reinforced Plastics at Volvo Car Corporation

  M. Landervik (DYNAmore Nordic), J. Jergeus (Volvo Car)

  A pilot study has been done at Volvo Cars Corporation (VCC) to explore the potential of Digimat as material model for car components made of short fiber reinforced thermoplastics. It has been a joint project between Safety and Durability departments. It thus spans several types of analyses using both LS-DYNA, Abaqus and Nastran as finite element solvers. Additionaly, nCode DesignLife is used for evaluation of fatigue.

• Discrete Element Analysis of Idealized Granular Geometric Packing Subjected to Gravity

  M. Faraone, J. Chung, M. Davidson (University of Florida, Bridge Software Institute)

  This paper presents discrete element analysis models for studying quasi-static stress states in idealized granular materials subjected to gravity, and utilizes geometric packings and contact mechanics. The theoretical description of granular materials in assemblies of microscopic particles is a challenging task. The particle assemblies characterize in-situ initial and boundary conditions. In turn, the conditions are used in solving the equations of motion of the particulate system under stress equilibrium states (via a network of particle contact forces and various degrees of dissipative interparticle friction).

• Drop Test Simulation and Verification of a Dishwasher Mechanical Structure

  O. Mulkoglu, M. A. Guler (TOBB University of Economics and Technology), H. Demirbag (Arcelik)

  It is critical for dishwasher manufacturers to design the front door hinge system and the structural components of a dishwasher assembly in terms of appearance and satisfying functional requirements. Since dishwasher users and customers request receptive quality elements from front door, it is necessary for example to know how many kilograms of decorative wooden door can be assembled to the built-in front door without endangering the durability on every single opening state.

• Ductile Fracture Prediction with Forming Effects Mapping of Press Hardened Steels

  L. Knoerr, T. Faath, S. Sikora (ThyssenKrupp Steel NA), P. Woelke, B. Benowitz, B. Hiriyur (Weidlinger Associates)

  The escalating usage of Advanced High Strength and Press Hardened Steels to enhance crashworthiness while improving fuel efficiency through light-weighting of vehicles, has become a surmountable challenge to the auto industry. Furthermore, the expanded safety assessment like the IIHS-Small Overlap crash test greatly intensify the need for an accurate and reliable fracture prediction model, that will take into account the forming effects of the structural components critical to the inherent load cases. In this study, a press hardened steel component with ultimate tensile strength of 1500 MPa with initial 1.5mm gage thickness, is investigated under experimental and virtual three point bending load conditions.

• Dummy-Positioning for a Whiplash Load Case using LS-DYNA Implicit

  A. Hirth (Daimler), A. Gromer (DYNAmore), T. Borrvall (DYNAmore Nordic)

• Edge-to-Edge Cohesive Shell Elements in LS-DYNA

  J. Karlsson (DYNAmore Nordic), M. Fagerström (Chalmers University)

  This paper presents a new cohesive element in LS-DYNA for edge-to-edge connection of quadrilateral thin shells. Cohesive elements are an important tool for simulating the propagation of cracks in materials.

• Enabling Effective and Easy to Access Simulation

  E. Schnepf (Fujitsu Technology Solutions), S. Gillich (Intel)

• EngineeringBrochure.pdf
• Evaluation of Kinematic Hardening Models for Multiple Stress Reversals under Continuous Cyclic Shearing and Multi-Step Bending

  S. Suttner, M. Rosenschon, Prof. M. Merklein (University of Erlangen-Nürnberg)

  In complex sheet metal forming processes the material undergo es various strain path changes, for instance, during the passing of a drawbead or a radius. Based on the Bauschinger effect that describes the material’s specific decrease of the yield stress after a load reversal, the resultant hardening behavior significantly differs from that o f a monotonic loading condition. For a reliable numerical process design, especia lly in springback analysis, a consideration of this effect is essential. Within this contribution , the evolution of the material behavior under cyclic loading is investigated with consecutive cyclic shearing of DP - K54/78+Z in a modified ASTM shear test. Mo reover , the kinematic hardening models according to Chaboche - Rousselier and Yoshida - Uemori are identified. In this context , the influence of the yield criterion and the capability of the different hardening models are analyzed. The applicability of the ide ntified parameters is finally evaluated in a multi - step bending process.

• Failure of Thermoplastics – Part 1: Characterization and Testing

  A. Fertschej, P. Reithofer, M. Rollant (4a engineering)

  Complex material models are much more used nowadays. The reasons are the increasing usage of plastics in high security relevance automotive and the resulting demand for virtual modeling including damage and failure.

• Failure of Thermoplastics – Part 2 Material Modeling and Simulation

  A. Fertschej, M. Rollant, P. Reithofer (4a engineering)

  Complex material models are much more used nowadays. The reasons are the increasing usage of plastics in high security relevance automotive and the resulting demand for virtual modeling including damage and failure.

• Fast Road Barrier Car Safety Calculations on a Cray XC

  J. Cholewinski, A. Findling, G. Clifford (Cray), M. Piechnik (Stalprodukt)

  Despite progress achieved in the last decade, 70 people die and more than 650 are seriously injured every day on Europe’s road. As one of the most cost-effective safety infrastructure solutions available to policy makers, vehicle restraint systems can greatly contribute to alleviating the consequences of road accidents and increase levels of safety on European roads.

• Forming Simulation of Textile Composites Using LS-DYNA

  M. Nishi, T. Hirashima (JSOL)

  The primary focus of this paper is on FE modeling and simulations performed to capture the material behaviors during a textile preform and a thermoplastic pre-preg forming manufacturing using LS-DYNA. Although an out-of-plane bending stiffness of textile reinforcement is often ignored as it is very low compared to in-plane stiffness, more accurate simulation, especially prediction of wrinkles, is achievable by considering out-of-plane bending stiffness in forming simulation. We propose a hybrid model which consists of a membrane and shells that can describe out-of-plane bending stiffness which is independent from in-plane behavior. In order to extend the textile reinforcement model to a thermoplastic pre-preg model for thermoforming simulation, temperature dependent stress contribution of thermoplastic is added to the textile reinforcement by applying Reuss model which can take the volume fraction of fiber into account.

• Fujitsu-HPC-cluster-link-collection.pdf
• Generalized Anistropic/Isotropic Porous Media Flows in LS-DYNA

  R. R. Paz, F. Del Pin, I. Caldichoury (LSTC), H. G. Castro (Conicet)

  In recent years industries like aerospace, automotive and those related to oil production have increased their trustfulness on numerical models and codes for the design, research, production and verification of highly critical parts and production processes. Most of these industries have adopted manufacturing procedures involving composites materials in liquid state, like the Liquid Composite Molding (LCM) and the High Pressure Resin Transfer Molding (HPRTM) methods, where a Newtonian (or Non- Newtonian) fluid flows through highly anistropic matrices filling an initially empty container.

• GOM Company Overview.pdf
• Ground Vehicle Aerodynamics using LS-DYNA

  F. Del Pin, I. Caldichoury, R. R. Paz (LSTC)

  The use of software for the simulation of airflow around ground vehicles plays an important role in the design of a vehicle. Traditionally companies within the automotive industry sector have a Computational Fluid Dynamics department dedicated to the analysis of drag and lift with the objective of improving fuel efficiency, safety, passenger comfort, cooling systems and heat exchangers and minimizing noise. In recent years the increased pressure from government regulators for dramatic improvements in fuel efficiency has pushed the automotive industry to start innovating in lighter materials and hybrid or full electric cars.

• H-Point Machine and Head Restraint Measurement Device Positioning Tools – Extended Capabilities

  B. Walker, L. Cowlam, J. Dennis (Arup), S. Albery, N. Leblanc (Futuris)

  The H-point of a seat is an important parameter for in the design process of a vehicle, and in particular the design of a seat. This can be estimated empirically, but this method is usually not sufficient to accurately determine how the manikin’s position is affected by subtle yet complex interactions within the seat and its trim. To aid this process, Arup have developed a positioning tool kit for use in conjunction with the Oasys PRIMER software [1]. The positioning tool kit calculates the H-Points of the automotive seats, as well as the backset measurement, thus providing the scores of the head restraint.

• Hail Impact Problem in Aeronautical Field

  A. Prato, M. Anghileri, L. Castelletti (Politecnico di Milano)

  Crashworthiness is one of the aspects that must be taken into account till the design phase, especially in aeronautical field. Some bodies, impacting against structures, can be considered as soft body. Soft bodies are highly deformable and flow over the structure spreading the impact load. Among them, hail impact can be considered as one of the most dangerous event during the operative life of aircrafts.

• Highly Advanced M&S System for Marine Accident Cause Investigation using FSI Analysis Technique

  S. Lee (Korea Maritime and Ocean University)

  Investigation of marine accident causes usually depends on the judgments of maritime experts, based on the statements of the concerned persons in the case where there is no navigation equipment, such as AIS and VDR. Scientific verification also has a limitation in the case of their conflicting statements. It is necessary to develop a highly advanced Modeling & Simulation (M&S) system for the scientific investigation of marine accident causes and for the systematic reproduction of accident damage procedure. To ensure an accurate and reasonable prediction of marine accident causes, full-scale ship collision, grounding, flooding and sinking simulations would be the best approach using hydrocode, such as LS-DYNA, with its Fluid-Structure Interaction (FSI) analysis technique and propulsion force for ship velocity

• HPC Manufacturing White Paper.pdf
• HPC on the Cloud: Gompute Support for LS-DYNA Simulations

  I. Fernandez, R. Díaz (Gridcore)

  Gompute delivers comprehensive solutions for High Performance Computing, in-house, in the cloud or both. With over 10 years’ of experience providing solutions and services to the Engineering communities, Gompute delivers a collaborative and productive infrastructure to either manage your HPC environment or burst out into the Gompute data center , ranging from 1 > 1000’s of cores. Keywords: Cloud Computing, LS-Dyna on demand, HPC simulations, flexible capacity.

• Impact Simulations on Home Appliances to Optimize Packaging Protection: A Case Study on a Refrigerator

  D. Hailoua Blanco, A. Ortalda (Engin­soft), F. Clementi (Electrolux Italia)

  Numerical simulations were used to investigate the impact behavior of complex products such as home appliances. LS-DYNA® is a powerful tool for performing repeat analysis of large assembled parts of the final product, including the packaging. The main goal of the simulations was to verify the performance and suitability of the packaging and its interaction with the structure in case of damage occurring during transportation or delivery. The studies were carried out to guarantee the integrity of the product from factory to customer and therefore to reduce customers service calls.

• Implementation of Peridynamic Theory to LS-DYNA for Prediction of Crack Propagation in a Composite Lamina

  T. Kahraman (MAN Turkey/ TOBB University of Economics and Technology), U. Yolum, M. A. Guler (TOBB University of Economics and Technology)

  Composite materials are commonly used in aerospace and automotive industry due to their high specific strengths. However, damage tolerance assessment of composite parts is done experimentally since there is no single criterion that is capable of predicting all of the failure modes. Thus numerical estimation of crack propagation in composite structures has been considered as an important research topic in academia and especially in aerospace industry. Composite materials are sensitive to stress raisers such as fastener holes and defects.

• Improvement of Domain Decom­position of LS-DYNA R7 and R8

  M. Makino (Dynapower)

  The domain decomposition is important for get the good performance by mpp version. The calculation of ls-dyna is mainly two parts; element calculation and contact calculation. For element calculation, ls-dyna can distribute the elements equally based on the cost evaluation. Until r6, the cost for solid element was not correctly treated, but r7, the cost of element including the solid element are re-evaluated.

• Improvements to LS- DYNA Implicit Mechanics

  R. Grimes (LSTC)

  LSTC is continually improving the capabilities and performance of Implicit especially in the distributed memory computing environment. This talk will review recent improvements such as (a) removing serial memory restrictions with a new matrix ordering algorithm, (b) reusing the matrix ordering when the matrix structure has not changed from the previous factorization (c) general improvements to performance of the numerical factorization. We will demonstrate these improvements with a series of industrial benchmark problems.

• Improving Robustness of Chevrolet Silverado with Exemplary Design Adaptations Based on Identified Scatter Sources

  D. Borsotto (Sidact)

  The investigations described here are related to the unstable behavior of crash-simulations due to minor changes in the model. As a consequence the received simulation results become in some way unpredictable, whereby the causes can be various: e.g. modeling failure, contact issues, numerical instabilities, physical instabilities, etc

• Increasing Efficiency of the Design Process with an Isogeometric Analysis Plugin for Siemens NX by Analyzing the CAD Model Directly

  M. Breitenberger, B. Philipp, R. Wüchner, K.-U. Bletzinger (Technical University Munich), S. Hartmann, A. Haufe (DYNAmore)

  The bottleneck for today’s integrated CAD and CAE tools or for the design-through-analysis process in general is the fact that for each product at least two different geometry representations are used. On the one hand side there is the CAD model and on the other hand side there is the finite element mesh, both representing the same object. The conversion between CAD model and FE model are named meshing and CAD reparameterization, respectively. These operations are error prone, time consuming and cannot fully be automatized.

• Influence of Variations in a Mechanical Framing Station on the Shape Accuracy of S-Rail Assemblies

  K. Wiegand, T. Konrad, (Daimler), M. Merklein (University of Erlangen-Nürnberg)

  In virtual production planning, recent publications showed the possibility of creating a digital process chain of body parts including the process steps in the press shop and body-in-white shop. The digital process chain is used to get an early impression of the shape accuracy of assemblies regarding the used single parts. Within the entire process chain a huge variety of factors influence the shape accuracy of (sub)assemblies. However, not every parameter of the deep drawing and assembly process exerts significant influence on the assembly quality and on process stability.

• Investigation of Seat Modeling for Sled Analysis and Seat Comfort Analysis with J-SEATdesigner

  N. Ichinose, H. Yagi (JSOL)

  Recently vehicle model is becoming more detailed and complex. Due to refinement of vehicle model, automotive companies are demanding to directly evaluate dummy injury criteria in crush analysis. To evaluate injury criteria, more detailed seat model is needed, because injury criteria are highly depending on seat structure and restraint system. Seat structure consists from metal frame, foam pad, covering fabric and complex mechanism.

• Isogeometric Analysis in LS-DYNA: Using CAD-Geometry for Numerical Simulation

  Prof. D. Benson (University of California), D. Bhalsod, P. Ho, L. Li, W. Li, A. Nagy, I. Yeh (LSTC), S. Hartmann (DYNAmore)

  In the last decade numerous research has been done in the area of Isogeometric Analysis (IGA). The intention of this rather new technology is the wish to have a stronger integration of Computer Aided Design (CAD) and Finite Element Analysis (FEA). Its basic idea is to use the same mathematical description for the geometry as well in the design process (CAD) as in the later analysis (FEA). One of the wide spread geometry description methodology in CAD-systems is the usage of Non-Uniform Rational B-Splines (NURBS) as basis functions.

• Joint Analytical/Experimental Constitutive and Failure Model Development

  P. Du Bois (Consultant); J. Seidt (Ohio State University)

• Keep the Material Model Simple with Input from Elements that Predict the Correct Deformation Mode

  Prof. T. Tryland (Sintef Raufoss Manufactu­­ring), T. Berstad (Norwegian University of Science and Technology)

  The 64 km/h frontal offset test is run with a deformable barrier, and the first numerical model of this barrier was made with solid elements to represent the honeycomb blocks. However this required development of a special element formulation to handle the severe deformation of the solid elements together with a special material model that could be calibrated to handle the extreme anisotropy. It is herein important to notice the amount of work, the uncertainties with the test specimens and the test procedure to get a proper representation of the honeycomb material.

• Lenovo Solution for Engineering Analysis.pdf
• LS-DYNA Air Blast Techniques: Comparisons with Experiments for Close-in Charges

  L. Schwer (Schwer Engineering), H. Teng (LSTC), M. Souli (University of Lille)

  Numerical simulations used to predict events are always challenging. Among the challenges is establishing some basis for confidence in the results when no experimental results exist, i.e. a prediction.

• LS-DYNA Model Development of the Harmonized Hybrid III 05F Crash Test Dummy

  C. Shah (Humanetics Innovative Solutions), C. Kleeßen, R. Kant, P. Lemmen (Humanetics Europe)

  Starting per January 2015 Euro NCAP requires use of the HIII-5th percentile small female for its full width frontal barrier test procedures. The dummy should be according to the latest agreed FTSS / Denton brand harmonization and thereby eliminates brand variability effects. The dummy configuration includes a neoprene neck shield, the SAE harmonized jacket (SAE J2921) and the Denton lower leg cavities. In addition, the thorax pendulum certification should be done for both 3.

• LS-DYNA Model Development of the THOR-M

  I. Maatouki, P. Lemmen (Humanetics Europe), Z. Zhou (Humanetics Innovative Solutions)

  Developments on the THOR dummy over the past years resulted in the THOR-M version which is foreseen for introduction into regulatory and Consumer tests in the 2020 timeframe. NHTSA considers to use the THOR-M dummy in an angled impact test while Euro NCAP includes plans for the development of a frontal barrier test with THOR-M in their roadmap for 2020. To support the development of restraint systems for both test configurations Humanetics is developing a Finite Element model of the THOR-M dummy.

• LS-DYNA-Brochure.pdf
• LS-TaSC Product Status

  K. Witowski, P. Schumacher (Dynamore), W. Roux (LSTC)

  The LS-TaSC Version 3.1 topology and shape design tool is presented. The presentation introduces the multi-point numerical derivatives scheme that allows constrained optimization using the mass fractions and load case weights as variables. This allows constrained optimization using any response or mathematical expressions as constraints or objectives.

• Machine Learning Approaches for Repositories of Numerical Simulation Results

  Prof. J. Garcke, R. Iza Teran (Fraunhofer SCAI)

  Simulations are used intensively in the developing process of new industrial products and have achieved a high degree of detail. In that workflow often up to thousand finite element model variants, representing different product configurations, are simulated within a few days. Currently the decision process for finding the optimal product parameters involves the comparative evaluation of large finite element simulation bundles by post-processing each one of those results using 3D visualization software. This time consuming process creates a severe bottleneck in the product design and evaluation workflow.

• Macroscopic Modeling of Flow-Drill Screw Connections

  J. K. Sønstabø, D. Morin, M. Langseth (Norwegian University of Science and Technology)

  In the last decades, the use of polymeric materials in the automotive industry has increased dramatically. This demand is linked to the good ratio between cost, density and mechanical properties for this class of materials . Moreover, injection modelling allows a very large range of shapes for the polymeric parts used in a car body. This combination of advantages makes polymers an ideal choice for automotive applications such as interior body parts as well as exterior bumpers.

• Macroscopic Modeling of Flow Drill Screw Connections

  J. K. Sønstabø, D. Morin, M. Langseth (Norwegian University of Science and Technology)

  Flow-drill screws (FDS) are used in the automotive industry to join parts in the load-bearing structure of cars. The process is a simple one-step procedure, which requires access only from one side of the assembly, and a variety of dissimilar materials may be joined. As it is easy to automate, the FDS technology is well suited for the production lines in the automotive industry.

• Making HPC Accessible for SMEs

  A. Wierse (Sicos BW)

  Numerical computation, often also named simulation, plays nowadays in many enterprises an important role in the development process. Especially in large companies in the automotive or aerospace industry it is actually impossible to develop a new product without simulation technology. In recent decades the necessary know-how and personnel has been built up, but there have also been and will be significant investments into the infra structure. Investments of a size, that can easily be handled by large companies, can be a real challenge for an SME.

• Mechanical Response Modeling of Different Porous Metal Materials

  Prof. M. Vesenjak, M. Borovinšek, A. Kovačič, M. Ulbin, Z. Ren (University of Maribor)

  Porous metals have been increasingly used in modern engineering applications over the past decades due to their multi-functionality and attractive combination of mechanical and thermal properties [1]. The understanding of their mechanical behaviour is of crucial importance for their use in engineering applications.

• Meta-Model Based Optimization of Spot-welded Crash Box using Differential Evolution Algorithm

  A. Serdar Önal, Beyçelik Gestamp Kalip ve Oto Yan San. Paz ve Tic.), N. Kaya (Uludağ University)

• Micro-Meso Draping Modeling of Non-Crimp Fabrics

  O. Vorobiov, T. Bischoff, A. Tulke (FTA Forschungsgesellschaft für Textiltechnik Albstadt)

  Composite materials with textile reinforcements are showing rapid growth of integration in aerospace, automotive, sport and other industrial sectors. Especially non-crimp fabrics (NCF) are widely spread because of their high drapeability and good in-plane mechanical properties in main fibre directions. For prediction of mechanical response of composite parts in particular with high curvature it is important to consider the local orientations and gaps in textile structures obtained after draping. Draping simulations are performed on meso-scale structure for this reason.

• Model Based Design of Pressure Profiles for Pyrotechnic Actuator using SPH Method & LS-OPT Solution

  E. Kantor, Y. Lev (Rafael)

  Pyrotechnic Pistons are communally used as fast reacting actuators in many elds and applications, such as seat belt pretensioners, wire and cable cutters and power disconnect devices. The design of such devices is subjected to many unknowns and the design methodology sometimes consists of many experiments in a trial & error methodology. This paper presents the design process of such a device. In this work a MBD process was applied using LsDyna® model and LsOpt® optimized solution for reaching upper and lower bounds for the pressure proles of a pyrotechnic device. The numerical solution decreases the number of required experiments in the design process and cuts its costs.

• Model Reduction Techniques for LS-DYNA ALE and Crash Applications

  K. Kayvantash, A.-T. Thiam (CADLM), S. B. Chaabane, J. Touzeau (Silkan)

  Model Reduction Techniques (MRT) are algebraic approximation solutions allowing for fast (real- time) interpolations (reconstruction) or extrapolations (prediction), based on previously existing DOE-type results, obtained either from FE computations or directly from constructions of reduced FE solutions. In a sense reduced models are subsets or decomposed domains of the solutions allowing for reconstruction of all spatial or temporal domain response. Contrary to FE where global interpolations are based on local "shape" (geometrical) functions, reduced models are based on basis functions which include not only geometrical but also material, boundary conditions and loading. This contributes greatly to fast solver solutions for on-board computing and may be used for time dependent approximations.

• Modeling Adhesively Bonded Joints with *MAT252 and *MAT_ADD_COHESIVE for Practical Applications

  F. Burbulla (Dr. Ing. h.c. F. Porsche), A. Matzenmiller, U. Kroll (University of Kassel)

  The new material model *MAT_TOUGHENED_ADHESIVE_POLYMER ( *MAT_252 ) has been developed at the Institute of Mechanics of the University of Kassel [1], [2] and become available for the use with solid elements since LS-DYNA R7.1.1 . The theoretical framework of the model equations is based on continuum and damage mechanics in order to predict the complex mechanical behaviour of crash optimized high-strength adhesives under combined shear and tensile loading.

• Modeling Non-Isothermal Thermoforming of Fabric-Reinforced Thermoplastic Composites

  D. Schommer, M. Duhovic, J. Hausmann (University of Kaiserslautern)

  The correct modeling of the sheet forming of fabric reinforced thermoplastic composites, so called organosheets, is still a challenge. In the past it was possible to predict accurately and efficiently the fiber orientation during the draping of dry reinforcement or constant temperature organosheet (reinforcement and molten polymer) using the explicit FEM-Software LS-DYNA®. Until now, the developed model was only able to simulate the right material behavior for an isothermal process. However, the draping of an organosheet is in reality a non-isothermal process that takes place at elevated temperatures.

• Modeling of Ballistic Impact of Fragment Simulating Projectiles against Aluminum Plates

  T. Fras, L. Colard, B. Reck (French-German Research Institute of Saint-Louis)

  In this paper, the ballistic impact test is described in which fragment simulating projectiles (FSPs) have been used against thick plates made of an aluminum alloy. To perforate the plates, the projectiles must have reached velocities higher than 890m/s.

• Modeling of Self-Piercing Riveted Joints for Crash Simulation – State of the Art and Future Topics

  M. Bier, S. Sommer (Fraunhofer IWM)

  The requirements for energy efficiency and lightweight construction in automotive engineering rise steadily. Therefore a maximum flexibility of different materials is necessary and new joining techniques are constantly developed. The resulting large number of joints with different properties leads to the need to provide for each type of joint an appropriate modeling method for crash simulation.

• Modeling of Strain-Rate Dependence of Deformation and Damage Behavior of HSS- and UHSS at Different Loading States

  A. Trondl, D. Sun (Fraunhofer IWM)

  The predictive capability of crash simulation concerning material failure is still in need of improvement due to the coupled complex influences of triaxiality, strain rate and temperature. Because of their lower ductility the use of high- and ultra high strength steels (HSS&UHSS) requires a more accurate prediction of failure. This subject commonly leads to more complicated material- and failure models to describe complex interactions between deformation, strain rate and temperature, which usually results in longer computational time. On the other hand, due to the high complexity of crash simulation structures, simpler and less time-consuming material models and numerical methods are required to keep simulation times in an acceptable frame.

• Modeling of Thick UD Composites for Type IV Pressure Vessels

  R. Matheis, H. Murnisya (fka Aachen), T. Johansson (DYNAmore Nordic)

  Increasing energy costs, limitation of crude oil resources as well as constantly intensifying emission targets (especially w.r.t. CO 2 ) are a pivotal driver for current automotive research and development.

• Modeling the Behavior of Dry Sand with DEM for Improved Impact Prediction

  S. Sridhar, S. K. Vishwakarma (Whirlpool of India)

  Pumpkin ball impact test is similar to simple pendulum impact test. It represents a rough handling test conducted on user interface parts to check its robusteness in case of abuse loading. The objective of this work is to create a standard simulation model that would capture the behavior of sand particles inside a rubber ball and scope is limited to create and validate a finite element model used to replicate a pumpkin ball impact test. Pumpkin ball is a rubber ball filled with dry sand up to 3/4th of its volume.

• Modeling the Press Hardening Process

  Prof. M. Oldenburg (Luleå University of Technology)

• Modelling of Adhesively Bonded Joints with *MAT252 and *MAT_ADD_COHESIVE for Practical Applications

  F. Burbulla (Porsche AG), A. Matzenmiller, U. Kroll (IfM, University of Kassel)

• MPP Contact: Options and Recommendations

  B. Wainscott (LSTC)

  There are many different contact algorithms currently implemented in LS-DYNA, each having various options and parameters. I will discuss only a few of them. Much of what is covered will only apply to the MPP version of LS-DYNA. I will start with some general background information, and then give details about some of the more interesting recent options that you might find useful.

• Multi-Scale Material Parameter Identi­fication using LS-DYNA and LS-OPT

  N. Stander, A. Basudhar, U. Basu, I. Gandikota (LSTC), V. Savic (General Motors Company), X. Sun, K. Sil Choi, X. Hu (Pacific Northwest National Labora­tory), Prof. F. Pourboghrat, T. Park, A. Mapar (Michigan State University), S. Kumar, H. Ghassemi-Armaki (Brown University), F. Abu-Farha (Clemson University)

  Ever-tightening regulations on fuel economy and carbon emissions demand continual innovation in finding ways for reducing vehicle mass. Classical methods for computational mass reduction include sizing, shape and topology optimization. One of the few remaining options for weight reduction can be found in materials engineering and material design optimization. Apart from considering different types of materials by adding material diversity, an appealing option in automotive design is to engineer steel alloys for the purpose of reducing thickness while retaining sufficient strength and ductility required for durability and safety.

• Multidisciplinary Design Optimisation Strategies for Lightweight Vehicle Structures

  A. Prem, C. Bastien, M. Dickison (Coventry University)

  The future of automobiles will be driven by lightweight structures and highly efficient powertrains. The TARF-LCV EPSRC funded project (Towards Affordable, Closed-Loop Recyclable Future-Low Carbon Vehicle Structures) aims to provide a strong scientific and technological underpinning to future LCV development in areas of advanced materials, low carbon manufacturing technologies, holistic mass-optimised vehicle structure design and closed-loop recycling of End of life vehicles.

• New Developments in LoCo – the Innovative SDM System

  M. Thiele (SCALE)

  DYNAmore GmbH has founded a new wholly-owned subsidiary known as SCALE GmbH. The aim behind this move is to offer software solutions and IT services for process and data management and for FE methods development in the automotive industry. In the past years, DYNAmore has created a variety of different software products under contract of AUDI. The reason for establishing SCALE GmbH is to further develop and market LoCo and other software products both within the Volkswagen group and beyond it as well.

• New Technologies for Side Impact Model Set-Up

  T. Fokylidis, A. Lioras (BETA CAE Systems)

  During the development and design process of a vehicle, Occupant protection in side impact studies has become a standard analysis. One of the most important issues that analysts face in side impact is how the passenger’s seat and the dummy will be adjusted in the proper position for the laboratory tests. This makes the application of numerical simulations inevitable. Simultaneously, as new legal tests and regulations are continuously introduced, the amount of relative loadcases has increased dramatically.

• Non-Linear Fracture Mechanics in LS-DYNA and LS-PrePost

  P. Lindström (University West/DNV GL Materials Laboratory), A. Jonsson, A. Jernberg (DYNAmore Nordic), E. Østby (DNV GL Materials Laboratory)

  In non-linear fracture mechanics, an energy based criterion is used for assessing the risk for crack growth: if the energy release rate at the crack tip exceeds what is required for creating new surfaces in the material, crack growth will occur. Under certain assumptions the energy release rate at the crack tip can be calculated by a path independent integral, the so-called J-integral.

• Non-Structural Mass Modeling in Aircraft Impact Analysis using Smooth Particle Hydrodynamics

  M. Kostov, M. Miloshev, Z. Nikolov, I. Klecherov (Risk Engineering)

  The non-structural mass in the large commercial airliners includes fuel, cargo, passengers, luggage, seats, lockers, etc. The straightforward approach for modelling of this non-structural mass is to include it as additional mass density to the corresponding structural elements. This approach would lead to conservative results in case of impact as the non-structural mass remains attached to the aircraft for the entire duration of the calculation, resulting into an overestimated impact effects. Alternative approach for modelling of non-structural mass is the application of the Smooth Particle Hydrodynamics (SPH) method.

• Nonlinear Analysis 1980 - 2020

  M. Lawson (Rolls-Royce)

• Numerical Analysis of Multistep Ironing of Thin-Wall Aluminium Drawpiece

  L. Brodawka, M. Kociolek, M. Siedlik, R. Budzyn, A. Furman (Can-Pack), A. Rekas, T. Latos (AGH University of Science and Technology)

  This work presents results obtained from numerical analysis of ironing with use of finite element mesh. The base drawpiece, that was a starting point in the analysis, includes a full history of deformation that resulted from simulations of preceeding operations, that is drawing and redrawing. Such a complex approach allows for a complete analysis of each successively conducted process. In the case of materials of thicknesses smaller than 0.

• Numerical Analysis of Relationship between Height and Geometry of Bottom of a Beverage Can and its Resistance to Increase in Internal Pressure

  L. Brodawka, M. Kociolek, M. Siedlik, R. Budzyn, M. Fijalkowski (Can-Pack), T. Latos, A. Rekas (AGH University of Science and Technology)

  Dome reversal pressure test is one of crucial quality tests required of such products as beverage cans. It gives information about resistance of a bottom in conditions of increased internal pressure. The information is important both for producers of carbonated beverages and final users. The test identifies the maximum internal pressure, which does not cause reversal buckling of a dome.

• Numerical Investigation of Carbon Braided Composites at the Mesoscale: Using Computer Tomography as a Validation Tool

  M. Vinot, M. Holzapfel, R. Jemmali (German Aerospace Center)

  So far analytical and, to a lesser extent, numerical approaches have been limited in their ability to predict the properties of braided composites because of the high complexity of the rovings’ interlacing. While many analytical theories have been developed to approach the stiffness of braided composites, only few models are able to reproduce their behaviour up to the global failure. As part of the research campus ARENA2036, which groups together partners from the industry and from research facilities, the DigitPro (Digital Prototype) project aims to develop a closed process chain for the manufacturing of braided composite parts, including, amongst others, braiding, draping and infiltration simulations as well as virtual material testings. The numerical material characterisation relies on the generation of an idealised geometrical model, using the open-source software TexGen, as a basis for finite-element simulations.

• Numerical Investigation of the Nozzle Number on the Performance of Conical Vortex Tube

  M. Guen, O. Imine, A. Miloud (University of Science and Technology of Oran Algeria)

  A three dimensional computational fluid dynamic is used to analyze the mechanisms of flow inside a vortex tube. The K- ω SST turbulence model was applied to predict the performance and turbulent flow behavior inside the tube. The performance is related to the nozzle number. Five different nozzles as two, three, four, five and six were tested.

• Numerical Methodology for Thermal-mechanical Analysis of Fire Doors

  A. Bozzolo, C. Ferrando (D’Appolonia - RINA Group), A. Tonelli, E. Cabella (RINA Group)

  The certification process of a fire door implies that the structure is subjected to a standard fire test, to evaluate its resistance to thermal load. In particular, the door must fulfil specific requirements, such as, that the gaps among the door labyrinths and frame are able to stop flame propagation and that the mean and maximum temperature on the unexposed surface does not exceed defined values. The present paper describes the numerical methodology used to assess the fire performance of large fire doors (single leaf and double-leaf sliding doors), having a length of the order of 15-25m, commonly used for civil/industrial applications. These fire doors cannot be tested at lab scale, due to their size, and the only way to verify their structural integrity when subjected to fire is via numerical simulations

• Numerical Simulation of Impact Welding Processes with LS-DYNA

  C. Pabst, P. Groche (Technical University Darmstadt)

  Impact welding enables metallurgical bonding even between dissimilar metals. The bond is formed during a high speed impact between the two workpieces to be joined. In the application, the accelerating force is provided by an explosive (explosion welding, EXW) or by an electromagnetic field (electromagnetic pulse welding, EMPW). One workpiece is usually accelerated within a few millimeters up to 200m/s and above

• Numerical Simulation of the Laser Scoring Line Behavior in Airbag Deployment

  M. Nutini, M. Vitali (Basell Poliolefine Italia), S. Bianco, D. Brancadoro, A. Luera, D. Marino (FCA), M. Olivero (CRF)

  The airbag door system is one of the most delicate aspects in the design phase of a car instrument panel: seamless systems are increasingly used, which combine styling criteria with good functional performances. These systems typically include a tear seam, which may be obtained through laser scoring , to pre - determine the location of the opening during airbag deployment. The desig n of the scoring line is currently validated through experimental tests on real life exemplars, submitted to airbag deployment, resulting in high development times and relevant costs. This is the main reason which suggests proposing numerical simulation in the design phase, not to substitute actual part homologation by testing but in order to limit the scope and complexity of the experimental campaign, thus reducing the development costs and the time to market.

• On Automatic Crash Model Translation

  E. Di Pasquale (SimTech/ Université de Valenciennes)

  This paper discusses some issues relevant to automatic crash model translation (conversion), based on SimTech experience. Automatic crash model conversion is in many ways similar to automatic language translation. The first level of conversion is “literal” translation, where each entity in the source model is translated into a corresponding entity in the target model. This issue is already complicated because such a target entity may not exist or may not be uniquely defined.

• Optimal Forces for the Deceleration of the ES-2 Dummy

  J. Fehr, J. Köhler, C. Kleinbach (University of Stuttgart)

  The purpose of this project is to improve the development process of vehicle safety systems by introducing a new analytic approach. Today, the development of vehicle safety systems, especially the airbag design process, requires many iteration loops via simulations and experiments. In this process, parameters are changed, a new simulation is conducted and the injury values are evaluated. We have a different, two folded approach: First we calculate the optimal forces to decelerate a dummy or human body.

• Optimization of a Lower Bumper Support regarding Pedestrian Protection Requirements using ANSA and LS-OPT

  I. Wetzstein, B. Lauterbach, N. Erzgräber, L. Harzheim (Adam Opel)

  A variety of pedestrian protection requirements must be considered during the vehicle development process, in order to improve the protection of vulnerable road users. The lower bumper support, which is located at the vehicle front (s. Fig. 1), is designed to generate beneficial leg kinematics from early in the impact.

• Optimization of the Blank Holder Stiffness in Deep Drawing Processes by using FEA

  R. Radonjic, Prof. M. Liewald, F. Han (University of Stuttgart)

  When deep drawing the parts with complex geometry, changeable thickening can occur in the flange area. Extreme thickening of the part flange will cause pressure peaks at the contact surface between blank holder and part. This undesired occurrence during deep drawing will reduce process window and process robustness as well. In this paper, an approach to optimize the blank holder stiffness in deep drawing process is presented.

• Optimization of Turbine Blade Fir Tree Root Geometry Utilizing LS-PrePost in Pre- and Postprocessing

  J. Jankovec (Research and Testing Institute Plzen)

  This paper describes geometry parameterization of turbine blade fir tree root prepared in LS-Prepost. The generated FE model utilizes LS-OPT in optimization loop. Simulation results of LS-DYNA implicit solver were used to extract required responses. Some problems arising during solving the task will be discussed in the article.

• Parameter Identification for Forming Simulations of High-Strength Steels

  M. Thomisch, Prof. M. Kley (University Aalen)

  Im Rahmen eines Forschungsvorhabens an der Hochschule für Technik und Wirtschaft in Aalen wird das plastische Umformverhalten von hochfesten Stählen, insbesondere Federstählen, untersucht. Im Detail stehen neben der klassischen Kenngrößen wie Fließgrenze und plastischer Verformung die Ver- und Entfestigungseffekte im Vordergrund der Betrachtung. Bei wechselnder Belastung im plastischen Bereich ist speziell bei hochfesten Stählen der Bauschingereffekt zu beobachten. Dieser lässt sich wie folgt charakterisieren.

• Performance Optimizations for LS-DYNA with Mellanox HPC-X Scalable Software Toolkit

  P. Lui, D. Cho, G. Shainer, S. Schultz, B. Klaff (Mellanox Technologies)

  From concept to engineering, and from design to test and manufacturing, the automotive industry relies on powerful virtual development solutions. CFD and crash simulations are performed in an effort to secure quality and accelerate the development process. The modern-day engineering simulations are becoming more complex and high in accuracy in order to model closely to the real world scenario. To accomplish such design simulations virtually on a cluster of computer systems, LS-DYNA® would decompose large simulation into smaller problem domains.

• Practical Failure Criterion of Spot Weld for Crash Simulation

  J.-H. Lim, J. Ha, C.-Y. Oh (Posco)

  This paper proposed a practical failure criterion of spot welds for combined loading condition for crash simulation. The tests were designed to obtain the failure load of a spot weld under combined loading condition. The seven types of experimental test were conducted to obtain the component of spot weld failure criterion. The failure criterion consists of moment component including normal and shear force.

• Predicting Mechanical Behaviour of Reinforced Plastic and Composite Parts

  S. Calmels (e-Xstream engineering)

  All the main industries worldwide are progressively adopting the usage of reinforced plastic and composite material for their product and have to face one major difficulty when it comes to design them: predicting the mechanical behavior of multi-phases and heterogeneous materials. On the structural side, each of these materials show a specific heterogeneous and anisotropic behavior in terms of stiffness, failure or electrical behavior as well as strain rate or thermal dependency fully driven by the microstructural organization of the reinforcements in the matrix. On the other side, the manufacturing process drives the final fibers orientation and distribution throughout the part. This means the design teams need a material and structural engineering technology able to create the link between the manufacturing process and the structural behavior of the components.

• Prediction of Dynamic Material Failure – Part I: Strain Rate Dependent Plastic Yielding

  M. Feucht (Daimler), R. Böhm (Karls­ruher Institut für Technologie), P. Du Bois (Consultant), F. Andrade, A. Haufe (DYNAmore)

  The dynamic behavior of materials plays a major role in crashworthiness. During a high speed crash event, the material undergoes different strain rates that may affect its constitutive behavior. For instance, in the first milliseconds of such an event, the strain rates near the contact region between the impacting and the impacted areas are extremely high. The strain rate then tends to rapidly decrease as energy is progressively dissipated during the crash.

• Prediction of Dynamic Material Failure – Part II: Application with GISSMO in LS-DYNA

  F. Andrade, A. Haufe (DYNAmore), M. Feucht (Daimler), R. Böhm (Karls­ruher Institut für Technologie), P. Du Bois (Consultant)

  As alluded in the first part of the present contribution, strain rate effects are quite relevant during a high speed crash event. If one intends to accurately predict failure under such conditions, it is important to properly understand and depict the underlying phenomena involved in such a scenario. For instance, the adiabatic heating that takes place during the plastic deformation process at high strain rates softens the material in such manner that the local plastic strain increases in critical zones. Also, localization is more pronounced in such critical zones due to the softening caused by adiabatic heating.

• Probabilistic Analysis of Process Chain “Forming to Crash“ Regarding Failure Prediction

  B. Özarmut, H. Richter (ThyssenKrupp Steel Europe), A. Brosius (Technical University Dresden)

  Numerical analysis of forming and crash processes is usually carried out deterministically. However, the variations of the parameters describing materials and processes cause significant deviations in the prediction quality. This observation becomes more important if the failure prediction in process chains like forming to crash is considered. Usually, the material and process parameters are identified by means of an inverse or a direct identification procedure using experimental data.

• Recent Advances on Surrogate Modeling for Robustness Assessment of Structures with Respect to Crashworthiness Requirements

  Prof. F. Duddeck, E. Wehrle (Technical University Munich)

  Due to the inherent nonlinearity, crashworthiness is one of the most demanding design cases for vehicle structures. Recent developments have enabled very accurate numerical simulations and corresponding optimizations. Therefore, structural concepts are now much better adapted to the specific requirements. This has led to designs in which redundancies are reduced and highly effective car concepts have been derived.

• Recent Developments for Thermo-Mechanically Coupled Simulations in LS-DYNA with Focus on Welding Processes

  T. Klöppel (DYNAmore), T. Loose (Ingenieurbüro Tobias Loose)

  With increased mechanical and functional requirements put on many parts produced by the manufacturing industry, the numerical simulation of the process has gained importance within the last years. The main objective when applying numerical tools is an accurate prediction of the finished geometry. In order to allow for an efficient optimization procedure in the design phase of the process the complete manufacturing process chain has to be included in the simulation. For many processes in sheet metal forming this is state of the art.

• Recent Developments in LS-DYNA – Part I

  J.O. Hallquist, B. Wainscott and other developers (LSTC)

• Recent Developments in the Electromagnetic Module: A New 2D Axi-Symmetric EM Solver

  P. L‘Eplattenier, I. Çaldichoury (LSTC)

  An electromagnetism module has being developed in LS-DYNA for coupled mechanical/thermal/electromagnetic simulations. More recently, a new 2D axi-symmetric version of this solver was introduced, allowing much faster simulations. In this solver, the EM equations are solved in a 2D plane, and the 2D EM fields, Lorentz force and Joule heating are then expanded to 3D elements by rotations around the axis. This allows to couple the 2D EM with 3D mechanics and thermal, thus keeping all the LS-DYNA 3D capabilities available.

• Recent Enhancements on Short-Fiber Reinforced Plastics Modeling in LS-DYNA

  C. Liebold, A. Erhart (DYNAmore)

  A two-scale constitutive model for short-fiber reinforced plastics is currently being realized in LS-DYNA associated with an appropriate data-mapper (DYNAmap). For reliable structural analysis of heterogeneous materials like SFRP, the anisotropic and locally varying effective elastic properties are determined through a homogenization process of the microstructure and provided for the structural analysis.

• Recent Updates in LS-DYNA Frequency Domain Solvers

  Y. Huang, Z. Cui (LSTC)

• Robustness Analysis of a Vehicle Front Structure Using Statistical Approach

  M. Okamura (JSOL)

  In this study, a process for assessing the robustness of designs has been presented, and the results are discussed using front structures of a vehicle FE model as an example. Statistical approaches have been introduced in order to assess the robustness of the structural design. Dozens of numerical simulations have been conducted taking into account uncertainties in input parameters such as spotweld failure criteria. The scatters in input parameters and the resultant deformations are statistically analyzed using a tool DIFFCRASH in order to capture the timing and location of bifurcations, and to understand the mechanisms inducing scatters in results.

• RollerPaG – a Tool for the Automatic Path Generation for Roller Hemming Simulation using LS-DYNA

  B. Boll (DYNAmore), O. Ghouati (Ford Research & Advanced Engineering)

  Compared to tool or table-top hemming, the roller hemming is unique by its specific kinematic. A robot guides a roller along the flange to perform the hemming, with more than one robot used for an assembly in order to speed up the process. Main advantages of the roller hemming are low investment for a new product and short lead time to design and manufacture product specific equipment. Application of roller hemming was up to now restricted to low and middle volume production, though new developments made it more suitable for higher production volumes as well.

• Scaling LS-DYNA on Rescale – HPC Cloud Simulation Platform

  J. Poort, I. Graedel (Rescale)

  Engineering and science simulations demand an increasing amount of computing resources. The majority of those resources consist of high performance computing (HPC) hardware, which are adaptable and highly efficient for running simulation software. Enterprises strive to create a lean and agile IT structure that both meets the current and unanticipated future needs of the various internal teams — without creating a cost structure that is unsustainable or disconnected from justifiable activities.

• Shock Response Analysis of Blast Hardened Bulkhead in Naval Ship under Internal Blast

  S.-G. Lee, H.-S. Lee, J.-S. Lee (Korea Maritime & Ocean University), Y. Y. Kim, G. G. Choi (Korea Advanced Institute of Science and Technology)

  It is necessary to restrict the damage area for the enhancement of ship survivability under the internal blast of a Semi-Armor Piecing (SAP) warhead inside a ship’s compartment, and to develop design guidance and performance verification technique of Blast Hardened Bulkhead (BHB) for the protection of its damage diffusion to adjoining compartment and continuous flooding.

• Short and Long Fiber Reinforced Thermoplastics Material Models in LS-DYNA

  S. Hartmann, T. Erhart, A. Haufe (DYNAmore), P. Reithofer, B. Jilka (4a engineering)

  In the last years the demand on weight reduction in the automotive industry has led to a strong interest for various composite applications. Due to the complexity of those usually highly anisotropic materials virtual product development is one of the key factors to understand the load carrying behavior of such parts. Furthermore enhanced CAE tools and models are necessary to ensure an efficient and robust product development.

• Simplified Integrative Simulation of Short Fibre Reinforced Polymers under Varying Thermal Conditions

  C. Witzgall, Prof. S. Wartzack (University of Erlangen-Nürnberg)

  The use of injection moulded, short fibre reinforced structural parts in vehicle design is increasing due to their low density and outstanding mechanical properties. As the distribution and orientation of fibres within the components are heavily dependent on the moulding process, product devel-opers do well to take process simulations into consideration before performing anisotropic struc-tural analyses. To enable the use of these integrative simulations within early design stages, a simplified approach has been developed by SCHÖPFER and extended by GRUBER/WARTZACK. It considers the material's anisotropy by using the fibre orientation data gained from the injection moulding simulation.

• Simulating the Induction Spot Welding of Hybrid Material Joints

  M. Didi, D. Wind, M. Duhovic, J. Hausmann (Technical University Kaiserslautern)

  Spot welding is a very common process used to join sheet metal components in the automotive industry mass production environment. Recently, thermoplastic composites as light weight alternatives to metals have begun to make their way into production. The induction spot welding of hybrid materials, in particular aluminum or steel to thermoplastic based composite materials, is one promising method to create the required connections between these dissimilar materials and maintain productivity. As opposed to continuous welding, the spot welding of two materials with different thermal properties can help prevent heat distortion and internal stresses in parts.

• Simulation Aspects for the Application of High Strength Steel Materials in Forming Processes

  L. Keßler, T. Beier, H. Richter (ThyssenKrupp Steel Europe)

  High-strength, cold-formable steels offer great potential for meeting cost and safety requirements in the auto industry. In view of strengths of up to 1200 MPa now attainable, some aspects need to be analyzed and evaluated in advance when designing with these materials. In addition to early assessment of crash properties, it is also highly important to design the forming process to match the material potential. To address the material potential by simulation a complete row of different tasks has to be fullfilled

• Simulation of Bird Strike on Airplane Wings by Using SPH Methodology

  M. Guler (TOBB University of Economics and Technology), T. Kiper Elibol (Turkish Aerospace), I. Uslan (Gazi University), M. Buyuk (Turkish Standards Institution)

  According to the FAA report, 142603 bird strikes were reported for a period of 24 years, between 1990 – 2013. Bird strike with aerospace structures not only threaten the flight security but also cause financial loss and puts life in danger. The statistics show that most of the bird strikes are happening with the nose and the leading edge of the wings. Also, a substantial amount of bird strikes are absorbed by the jet engines and causes damage on blades and engine body.

• Simulation of Circular Sawing Proccesses

  H. Vazquez Martinez (Fraunhofer IPA)

  Spanende Prozesse sind durch sehr hohe Dynamik und Verformungszuständen gekennzeichnet. Mit Hilfe der Simulationstechnologie sind bereits verschiedene Zerspanungsprozesse mit guten Ergebnissen analysiert worden. Obwohl sich Kreissägeprozesse durch sehr hohe Zerspanungsleistungen auszeichnen, wurden bisher kaum Simulationen auf diesem Gebiet durchgeführt. In der folgenden Arbeit werden Simulationen von Kreissägeprozessen mit LS-Dyna durchgeführt, bei denen die Einflüsse von Prozessparametern und Schneidgeometrien untersucht worden sind. Durch die Auswertung von FESimulationen sind geeignete Modellparameter sowie Optimierungspotenziale für die Simulation von Kreissägeprozessen ausführlich dargestellt.

• Simulation of Forming of Paperboard Packaging using LS-DYNA

  M. Schill, J. Karlsson (DYNAmore Nordic), J. Tryding (Tetra Pak)

  Paperboard is widely used as a package material for food and beverage. The ability to simulate the forming of the packages is of great interest, due to the variety in shapes and paperboard material structure combined with production speed. T

• Simulation of the Electromagnetic Flux Compression using LS-DYNA Multi-Physics Capability

  K. Takekoshi (Terrabyte)

  The Electro-Magnetic Flux Compression system can generate ultra-high magnetic flux over 700 T with an electromagnetically imploded coil and is employedto study electronic physical properties of condensed matterssuch as carbon nano-tubes.Predicting the generation of electro-magnetic flux using computer simulation techniquesrequires electro-magnetic –thermal –structural coupling analysis. Since the electromagnetism (EM) module has been introduced into LS-DYNA starting from Ver. R7.

• Simulation of the Manufacturing Process of Self-Piercing Rivets with LS-DYNA with Focus on Failure Pediction for Sheets and Rivet

  M. Buckley (Jaguar Land Rover), H. Gese, M. Reissner, G. Oberhofer (Matfem Partnerschaft)

  There are many two-sheet and three-sheet material combinations in a body-in-white which can be joined via self-piercing rivets (SPR). A physical trial-and-error approach to ensure the feasibility of all combinations would be very time consuming and expensive. In addition the physical manufacturing test will not deliver the amount of accumulated damage in the sheets which is relevant for the strength of the SPR in a successive crashworthiness load case. An appropriate virtual simulation of the manufacturing process can be used to assess manufacturability and to evaluate the accumulated damage.

• SimWeld and DynaWeld Software tools to setup simulation models for the analysis of welded structures with LS-DYNA

  Tobias Loose (Ingenieurbüro Tobias Loose), Oleg Mokrov (ISF Aachen)

  The analysis of residual stresses or distortion of welded structures requires a welding structure analysis. This kind of analysis incorporates some specifics compared to other FEM-simulations. Apart from the definition of geometry (mesh) and clamps, the welding structure analysis requires the definition of heat sources, trajectories and time schedules. The heat source applies the heat in the model according to the welding process. An equivalent heat source is used which needs to be calibrated for tests or predictively calculated from a welding process analysis. The trajectories describe the path of the moving welding heat source in the simulation model. Most welding heat sources are not rotational symmetric. Their trajectories require a path to define the local origin of the heat sources and a reference line to define the orientation of the heat source. Welding is a transient process where the time schedule of the actions - welding time, intermediate time - has an impact on the result. The process plan defines the welding time schedule and has to be considered in the simulation model.

• Small-overlap Crash Simulation Challenges and Solutions

  S. R. M. Arepalli, G. Kini, A. Gittens (ESI Group)

• Smart Manufacturing: CAE as a Service, in the Cloud

  W. Gentzsch (The UberCloud)

  The benefits for small and medium size businesses (SMBs) and research departments of using High Performance Technical Computing (HPTC) within their design and development processes can be huge. For example enormous cost savings; reducing product failure during design, development, and production; develop optimized processes; achieve higher quality products; and shorten the time to market or scientific result. Potentially, all this can lead to increased competitiveness, deeper insight, and more innovation. However, the vast majority of SMBs perform virtual prototyping or large-scale data modeling still on their desktop computers.

• Solving of Crash Problems of the Fuel Supply Modules in the Fuel Tank

  M. Dobeš, J. Navratil (Robert Bosch)

  This article in the first part deals with the experimental measurement of the material data used for explicit computational FEM analyses. The second part of this paper devotes practical application of the FEM simulation in fuel tank domain and fuel supply modules (FSM). The main focus is on the material computational models, especially material models with strain rate dependence. These computational models are used for polymer materials, like TSCP (Typical Semi-Crystal Polymer).

• Speeding up the Pedestrian Protection CAE Process

  G. Newlands, C. Archer (Arup)

  Pedestrian protection is increasingly important to the design and development of the front end of vehicles. The various protocols, impactors and methods relating to pedestrian protection mean that the CAE process can be complex and time consuming. Arup has developed various tools to aid in this process which are used internally within Arup when working on automotive consultancy projects as well as being available externally in the Oasys LS-DYNA® environment software. These tools are available for both head and leg impact analyses. This paper describes the tools and also how they have been used on real world projects.

• SPH Modeling of Cutting Forces while Turning of Ti6Al4V Alloy

  A. A. Olleak, H. El-Hofy (Egypt-Japan University of Science and Technology)

  A growing interest in modelling and simulation of machining processes has been witnessed in the past few decades. Smoothed particles hydrodynamics (SPH), one of the latest and developing methods used for that purpose, is a powerful technique that can be efficient in handling problems in which large deformation occurs. This technique is able to overcome the shortcomings of the traditional finite element methods. One of these shortcomings is the need to adopting a damage model that artificially initiates the crack, and therefore, the accuracy will be affected.

• Stability of THUMS Pedestrian Model and its Initial Trauma Response Against a Real-Life Accident

  L. Wen, C. Bastien, M. Blundell, C. Neal-Surgess (Coventry University), K. Kayvantash (CADLM)

  With dramatically rapid development of computing and modelling technology, occupant and pedestrian safety models went through the development of crash test dummies and multi-body mathematical dynamic modelling to finite element pedestrian human model (THUMS 4.0). THUMS 4.0 is a state of art human model which includes a skeleton structure, as well as internal organs and soft tissues, which makes it a suitable candidate to analyse accident trauma.

• Statistical Energy Acoustic for High Frequencies Analysis

  M. Souli, R. Messahel (University Lille), Y. T. Zeguer (Jaguar Land Rover), Y. Huang (LSTC)

  For high frequency analysis, Statistical energy analysis (SEA) has proved to be a promising approach to the calculation of sound transmission in complex structures. In automotive industry and also in civil engineering, most of noise transmission is due to high-frequency structural vibrations, where the characteristic wavelength is small compared to the dimensions of the structure.

• Stochastic Simulations for Crash Worthiness and Occupant Protection

  T. Yasuki (Toyota Motor)

  Reduction of mass of vehicle is a high priority of design targets in automotive industries. To achieve the design targets, several quality control methods are employed in crashworthiness and occupant simulations by LS-DYNA at Toyota Motor Corporation. Some topics using quality control methods in the simulations including LS-TASC are introduced, and its effectiveness and limitations are discussed.

• Strain-Rate Dependant Damage Material Model for Layered Fabric Composites with Delamination Prediction for Impact Simulations

  S. Treutenaere, F. Lauro, B. Bennani (University of Valenciennes and Hainaut Cambrésis), T. Matsumoto, E. Mottola (Toyota Motor Europe)

  The use of carbon fabric reinforced polymers (CFRP) in the automotive industry increased very significantly due to their high specific stiffness and strength, their great energy absorption as well as the reduced manufacturing cost. The behaviour understanding and modelling of these materials become essential for their implementation into the design loop, needed for the deployment on mass-produced vehicles. In order to ensure the protection of pedestrians and drivers/passengers in case of collision with a CFRP panel, a model dedicated to the finite element analysis (FEA) of impacts is needed. The nonlinear material behaviour which leads to differences in the impact response of composites is attributed to fibre failure, intra- and interlaminar matrix cracking, fibre-matrix debonding and strain rate sensitivity of the matrix

• Structural Analysis of an Automotive Forming Tool for Large Presses Using LS-DYNA

  K. Swidergal , Prof. M. Wagner (OTH Regens­burg), C. Lubeseder, I. von Wurmb, J. Meinhardt (BMW Group), S. Marburg (University of the Federal Armed Forces)

  To improve efficiency in automotive press shops, press systems with increasingly high stroke rates are being implemented, raising thereby the structural dynamic load on the press and especially on the forming tool. A detailed knowledge of the vibrations and resulting critical loads is thus essential for accurate and reliable designs of forming tools. In this paper, dynamic finite element method (FEM) simulation of a selected automotive tool is presented enabling the identification of the vibration of its components. Furthermore regions of critical stress of those structures can be determined.

• Textile and Composite Modeling on a Near Micro-Scale: Possibilities and Benefits

  O. Döbrich, T. Gereke, C. Cherif (Technical University Dresden)

  Textile materials are increasingly used in civil engineering for the purpose of reinforcing high performance composites, acting as membranes or fulfil technical tasks like filter contaminated media. Therefore, the demand for accurate numerical models which are able to predict the textile mechanics and the forming behaviour of dry and consolidated textiles is increasing and the requirements on the models accuracy and fineness rises. Many numerical models have been introduced in the literature for the different levels of objectivity. For macro-scaled models, complex material models have been carried out to account for the various deformation mechanisms and the anisotropic mechanic of textile fabrics.

• The CASIMIR Model for Simulation in Seating Comfort Applications – A Status Update for LS-DYNA

  N. Lazarov, D. Fressmann (DYNAmore), A. Siefert (Wölfel Beratende Ingenieure)

  For those who spend a lot of ti me driving, issues of comfort can become issues of health and safety. Therefore seating comfort is an important point in the seat development. Currently, the OEM and Tier - 1 are mainly using experimental setups with test drivers for the evaluation of seating comfort.

• The Effects of Active Muscle Contrac­tion into Pedestrian Kinematics and Injury During Vehicle-Pedestrian Collision

  I. Putra, J. Carmai, S. Koetniyom (King Mongkut’s University of North Bangkok), B. Markert (RWTH Aachen/University of Agder)

  The objective of this study is to develop a finite element model of active human skeletal muscle, which can mimic the contraction behavior of the skeletal muscle and also to analyze the effects of active muscle contraction into pedestrian kinematics and pedestrian injuries during vehicle-pedestrian collision. The skeletal muscles are modeled by combination of solid tetrahedral elements and line beam elements.

• The Influence of Johnson-Cook Parameters on SPH modeling of Orthogonal Cutting of AISI 316L

  A. A. Olleak, H. El-Hofy (Egypt-Japan University of Science and Technology), M. N. A. Nasr (Alexandria University)

  Over the past few decades, there has been a growing interest in modelling of machining processes. In this regard, smoothed particle hydrodynamics (SPH) is one of the latest methods used for that purpose. SPH is a powerful technique that can be used in handling problems of large deformation that are difficult to be tackled using traditional finite element methods. The current work aims to present and evaluate the use of SPH in modelling the machining process.

• The Numerical Failure Prediction by the Damage Model GISSMO in Various Materials of Sheet Metal

  S. Chinzei, J. Naito (KOBE Steel)

  Responding to continuous demands for weight saving and enhancement of collision safety of vehicles, high-strength steel sheets are widely used for car bodies. Also, the applications of aluminum sheets are increasing for seeking more lightweight, recently. In applying sheet metals with thinner thickness and higher strength to car bodies, numerical fracture predictions are strongly required to ensure collision safety, since the reduction of ductility becomes key issure for these materials. As a failure model, we use a well examined damage model GISSMO which includes incremental formulation for the description of material instability and localization.

• Three-Point Bending Crack Propagation Analysis of Beam Subjected to Eccentric Impact Loading by X-FEM

  T. Tsuda, Y. Ohnishi, R. Ohtagaki (Itochu Techno-Solutions), K. Cho, T. Fujimoto (Kobe University)

  When analyzing a failure or crack propagation problem by FEM, there are the following challenges to solve. (1)It’s necessary to make element boundary match to the failure surface or the crack surface. (2)The failure shape and the crack propagation direction depend on the mesh. (3)It’s necessary to express a singularity of crack tip field.

• Topology Optimization of Transient Nonlinear Structures – A Comparative Assessment of Methods

  E. J. Wehrle, F. Duddeck (Technical University Munich), Y. H. Han (Hyundai Motor Group)

  Topology optimization considering transient nonlinear behavior of mechanical structures, e.g. automotive crash, remains a challenge in both the implementation as well as computational effort. In recent years, efficient optimization algorithms and increased computer technology has begun to allow the development of methodologies to examine optimal topology of structures undergoing such behavior.

• Topometry and Shape Optimization of a Hood

  Y. H. Han (Hyundai Motor Group), K. Witowski, N. Lazarov, K. Anakiev (DYNAmore)

• Towards Location Specific Statistical Fracture Prediction in High Pressure Die Castings

  R. Watson, W. Griffiths (Univerity of Birmingham), T. Zeguer (Jaguar Land Rover); S. Ruffle (JVM Castings)

  High pressure die casting is an economical means of producing a high volume of aluminium parts, with a design freedom that can enable lighter structures to be envisioned, compared with wrought assemblies. However, cast aluminium parts have been shown to be vulnerable to damage by defects caused by the entrainment of air during the casting process. A recently developed entrainment prediction algorithm, which is believed to more quantitatively predict the distribution of entrainment defects within a casting, was used to predict the distribution of these defects for two variants of the casting process for a commercial part. Using a novel fuzzy statistical correlation method, the predicted distribution of entrainment damage was correlated with the statistical distribution of entrainment damage, as determined by tensile testing

• Usage of LS-DYNA in Metal Forming

  M. Fleischer, A. Lipp, J. Meinhardt, P. Hippchen, I. Heinle, A. Ickes, T. Senner (BMW Group)

• Use of Forming Limit Curve as a Failure Criterion in Maritime Crash Analysis

  B. Atli-Veltin, L. Vredeveldt (TNO)

  The crashworthiness of marine structures is one of the main area of interest of several parties active in maritime area. The ability of structural material to absorb mechanical energy without fracture, is a very important safety feature. For offshore structures, the general approach towards a fracture criterion is based on the Norsok standards. For inland waterways, it is based on ADN Guidelines.

• Using JFOLD & LS-DYNA to Study the Effects of Folding on Airbag Deployment

  R. Taylor (Arup), S. Hayashi (JSOL)

  Today's engineers and designers need accurately folded airbags in their deployment simulations. Minor changes in the way the airbag is folded can cause different deployment behaviour, which can lead to trim fracture, hang-ups and unintended injury. There is a growing demand for robust, accurate analysis to study and mitigate these problems, but creating an accurate model of a folded airbag is still a challenge. JFOLD is a software tool developed to meet the growing demand for fast and easy simulation based airbag folding.

• Using LoCo for Multi Run Simulations

  R. Luijkx (AUDI), M.Thiele (SCALE)

  For several years now AUDI and DYNAmore (now SCALE) have been working on a new generation of SDM-System called LoadcaseComposer, Short: LoCo. This SDM-System applies several new approaches to Simulation Data Management, such as strict offline capabilities with permanent synchronization of relevant data, consequent and strict version management of all related objects of simulations, novel ontology based approaches for the assembly of components as well as easy customizability and supporting a sustainable process by means of a “continuous integration” approach for frequent upgrades of the entire LoCo deployment.

• Validation of Fluid Analysis Capabilities in LS-DYNA Based on Experimental Result

  S. Tokura (Tokura Simulation Research)

  The latest LS-DYNA provides several excellent capabilities for modeling of fluid like materials. These capabilities contains ALE, SPH and CESE for compressible fluid and ICFD for incompressible fluid. Each capability has its own numerical method for computation and characteristics, and is used properly for different target of modeling and purpose of each simulation. For example, ALE and SPH can treat free surface problem automatically without any additional definition of free surface boundary, whereas, explicit definition of free surface boundary is required in ICFD computation.

• Verification of the Part-Composite Approach for Modeling the Multi-Layered Structure of a Rolling Truck Tire

  S. Shokouhfar, S. Rakheja (Concordia University)

  Accurate modeling of a truck tire for predicting dynamic characteristics requires an adequate representa- tion of its composite plies. This study compares two approaches in modeling the multi-layered structure of a rolling radial-ply truck tire using LS-DYNA. In the first approach, different layers in the tire structure are modeled using individual elements; whereas, in the second, all layers are represented by a single element with layered configuration managed by the PART_COMPOSITE keyword. Hence, in this article, these tire models are named as the Individual-Element (IE) model versus the Part-Composite (PC) model.

• Virtual Vehicle Company Overview.pdf
• Volume-Averaged Stress States for Idealized Granular Materials using Un­bonded Discrete Spheres in LS-DYNA

  M. T. Davidson, J. H. Chung, V. Le (Bridge Software Institute), H. Teng, Z. Han (LSTC)

• X760 Bumper Automation and Optimization Process

  T. Zeguer (Jaguar Land Rover)

  Currently the bumper system is developed through a wide variety of individual virtual test methods, the majority of which also have to be verified with physical testing. This paper will describe a new process that produced a one combined virtual process to encompass the full bumper as a system development method by creating One model for a bumper as one system with multiple attributes and requirements and using only one code “ LS-DYNA and LS-OPT”.