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11th European LS-DYNA Conference

Salzburg, 2017

Ductile Failure in Large-Scale Analyses of Aluminium Structures
D. Morin, T. Berstad, O.S. Hopperstad, M. Langseth (NNTU)
Modelling of ductile failure in aluminium alloys is of high importance during the design of lightweight structures subjected to impact loading. Such designs are today based on numerical analyses and their credibility is crucial to reduce the development time and costs of such products. Under impact conditions, lightweight structures are most likely exposed to severe loadings and failure is a phenomenon which cannot be ignored. To accurately ...
DynaWeld-Equivalent-Energy-Method
T. Loose (DynaWeld)
 
Efficient Global Optimization Using LS-OPT and its Parallelization
A. Basudhar, N. Stander, I. Gandikota (LSTC)
Simulation-based design has evolved significantly in the past few decades. While the computing resources have advanced, model complexity has also increased considerably to capture the physics in greater detail. Therefore, reducing the number of “expensive” samples needed to obtain an optimal design is very important. Also, parallel computing has now become widely available, making the simultaneous selection of multiple samples desirable for ...
Enhancements to Implicit Mechanics
R. Grimes, R. Lucas, C. Weisbecker, C. Ashcraft, F. H. Rouet, J. Anton (LSTC)
Solving large sparse linear systems of equations is often the computational bottleneck for implicit calculations. The team of developers at LSTC is working on many aspects of this linear algebra. This is the first of two talks describing this body of work. While the second talk will focus on the performance of the distributed memory linear equation solver, this talk will focus on other aspects of the overall solution process, often ...
Equivalent Energy Method for Welding Structure Analysis
T. Loose; J. Rohbrecht (DynaWeld)
Simulation means real physical processes are calculated on computers with numerical methods. The real world is substituted by a virtual world. The benefits on welding are: - predict the state before manufacturing - complex high costly physical tests are replaced by low costly virtual tests, - visualization of states of work pieces, which are not or hardly able to be measured, - automation of analysis and evaluation, which cannot be realized ...
Evaluation of Advanced Element Formulations for Failure Prediction of Highly Complex 3D-Printed Parts
S.Mohapatra (Sabic)
Additive manufacturing has moved beyond rapid prototyping and is now starting to be used for manufacturing of functional parts such as in aircraft engines and medical transplants. This has resulted in a paradigm shift in design requirements for 3D printed parts from simply aiding in rapid physical visualization of designs to sustaining operating loads. Furthermore, along with the functional load bearing requirements, 3D printed designs ...
Evaluation of Debris Modeling Technique on Failure Simulation of Concrete Structures
S. Tokura (Tokura Simulation Research); K. Niwa (Terrabyte)
It is a crucial issue to protect important buildings, especially nuclear power plants against large natural disaster or terrorist attack. Nuclear power plant is a concrete structure and highly accurate prediction of the failure modes, e.g., crack propagation, penetration and spalling is required at the impact of projectile. In reality, when concrete material is failed, the failed material is not deleted and piles up as debris instead. In the ...
Evaluation of Different Thermo-Viscoplastic Material Models under Simultaneous Hot/Cold Forging Conditions
M. Nahrmann, P Kühlmeyer, A. Matzenmiller (Universität Kassel)
The simultaneous hot/cold forging is an innovative metal forming process, which takes advantage of low forming forces in heated parts of the workpiece respectively high geometric accuracy in cold forged areas. For the finite element analysis of such processes, material models are required that take temperature and rate dependent plasticity into account. The material models *MAT_BAMMAN and *MAT_EMMI are available in the material library of ...
Experimental Investigation and Numerical Characterization of the Bake-Hardening Effect of a Two-Phase Steel
D. Koch, A. Haufe (DYNAmore); M. Feucht (Daimler)
Typically, the material characterization for the simulation is performed based on the virgin material, which is used for the preparation of the corresponding component. However, due to the processing of the material, its properties may vary greatly. Exemplarily, in Fig. 1, experimental results are shown based on the same material. The test specimens belonging to the red curve were pre-stretched and heated prior to the experiment, while the test ...
Experimental Investigation on the Damage Behaviour of a Rubben-Toughend Polymer
M. Helbig (DYNAmore)
Rubber-toughened polymers such as ABS are composed of a thermoplastic matrix and small rubber particles e.g. [1]. Macroscopic effects of the rubber particles are a reduced overall stiffness and yield strength and an enhanced ductility and fracture toughness [2,3]. These macroscopic effects are caused by mechanisms on the micro scale such as shear yielding, void growth and crazing [4]. In the present work experimental investigations on an ...
Experimental Validation of Detecting Surface Deflections on Sheet Metal Parts with LS-DYNA
A. Weinschenk, A. Schrepfer, W. Volk (TU München)
The appearance of surface deflections on sheet metal parts is undesirable. When surface deflections are detected on a sheet metal part during tryout, the tool geometry has to be modified. This procedure is performed at a later stage of the product development process which leads to high costs and effort. Therefore, it is useful to detect surface deflections before the actual production in the finite element simulation. Then, it is much ...
Explicit and Implicit FE Simulations of Material Tests for Subsequent Durability Analyses
P. Thumann, M. Wagner (OTH Regensburg); B. Suck (BMW); S. Marburg (TU München)
To improve the efficiency in sheet metal manufacturing, more and more press systems with increased stroke rates are in use. Due to the increased stroke rates, the structural-dynamic loads too increase. Thereby, not only the press systems are highly loaded, but also the tools for manufacturing the blanks. This has to be accounted for in the early design phase of the tools in the virtual process chain. Because of safety requirements, high safety ...
Failure Models of Plastics - Material Characterization for *MAT_ADD_EROSION (DIEM)
A. Fertschej, B. Hirschmann, M. Rollant, P. Reithofer (4a engineering GmbH)
The tensile test is a standard testing method for many different materials to determine elasticity, plasticity and failure. Due to DIC (digital image correlation) these tests are time consuming and in the case of dynamic testing also cost intensive. To characterize the dynamic deformation behavior dynamic bending tests on 4a impetus are a cost-efficient alternative.
FE Implementation of AA6xxx Series Aluminium Pre-Strain Dependent Strengthening Response During Paint Bake
S. Jurendic, Z. Liang, R. Burrows (Novelis); S. Saha (RWTH Aachen)
As the drive for light-weight materials in the automotive industry increases, so does the use of heat-treatable AA6xxx series aluminium alloys in both body panels and structural components. These alloys have a distinct advantage in that they can be formed in a soft state of temper and later on heat treated in the paint bake process to achieve a higher overall component strength. The material maintains good formability throughout the forming ...
Finite Element Modelling of a NiTi SMA Wire
W. L. H. Wan A Hamid, L. Iannucci, P. Robinson (Imperial College London)
The development of a Finite Element Model of a NiTi shape memory alloy (SMA) wire in a commercial explicit finite element software, Ls-Dyna, is presented. A user-defined material (UMAT) model has been developed by implementing one of the earliest one-dimensional SMA constitutive models, the Tanaka model [1], into Ls-Dyna through a FORTRAN code. The aim is to apply this model to develop a SMA-actuated morphing wing. Morphing has attracted ...
Forming of Ultra-High-Strength Sheet Metals with Alternating Blank Draw-In
R. Radonjic, M. Liewald (Universität Stuttgart)
Reduction of the vehicle weight and improvement of the passenger safety are permanently defined requirements for design and manufacturing of the dedicated car body components. One possibility to fulfil before mentioned requirements is use of thin walled ultra-high-strength steel sheets for manufacturing of the car body structural parts. However, when forming such kind of sheet metal materials, severe problems may result from the large amount of ...
Forming Simulation, Meta Language and Input Decks
M. Fleischer, J. Sarvas, H. Grass, J. Meinhardt (BMW Group)
The use of finite element (FE) simulations for a virtual validation of the forming process for sheet metal parts has been introduced in the mid 1990s and is state of the art in the automotive industry today. Two challenging tasks for determining whether a tool design and its process parameters are feasible are the prediction of the material behavior during the forming process and the springback of the final part. For improving the predictive ...
Forming Simulations of Niobium Sheets - Upgrade of the Numerical Model and Outcome for Novel Productions
A. Amorim Carvalho, M Garlaschè, A. Dallocchio, O. Capitana, L. Prever-Lori, M. Marduzzi, J. Brachet, B. Bulat (CERN); L. Peroni, M. Scapin (Politecnico di Torino)
The installation of superconducting Radio Frequency (RF) Crab Cavities is one of the key upgrades in the framework of the High Luminosity Large Hadron Collider (HL-LHC) at CERN. These devices – built out of niobium sheets – are shaped into a complex geometry entailing very tight tolerances, in order to comply with strict RF requirements. Numerical simulations via LS-DYNA proved to be a useful tool to optimize the fabrication process of these ...
Free Fall Movement Decomposition of a Payload Released by Aircraft: Study of the Aerodynamic Coefficients Using the LS-DYNA ICFD Solver
E. Grippon, M. Seulin, V. Lapoujade, T. Maillot, C. Michel (DynaS+)
Through its multiphysics aspect, the airdrop domain is chosen to demonstrate the new FSI capacities recently developed within the LS-DYNA software (more specifically using the ICFD solver). To do this, DynaS+, French, Spanish and Portuguese distributor of LS-DYNA and associated services got a research and innovative subvention from the French Government, RAPID financing. The main goal of this project, PARAFLU, is to succeed in modeling the ...
Free-Form Shape Optimization on CAD Models
D.Baumgärtner, M. Breitenberger, K.-U. Bletzinger (TU München)
A novel approach for the free-form shape optimization on CAD models is presented. The optimization workflow consists of three steps: - Creating a finite element mesh of the CAD model - Vertex-morphing for exploring the best design (Millions of DOFs possible) - Isogeometric B-Rep mapping for updating the CAD model The output of the proposed optimization workflow is a complete high-quality CAD model. The presented techniques allow ...
FSI with the Detailed Chemistry and their Applications in LS-DYNA® CESE Compressible Solver
I. Kyoung-Su, Z. Zhang, G. Cook (LSTC)
Recently, we have developed a new module of the modeling fluid structure interaction with the finiterate chemistry in compressible CESE solver, which is based on the immersed bounday FSI method, and fully coupled with the LS-DYNA® structual FEM solver. In the CESE fluid structure interaction solver, we have two principal treatment methods, i.e., the immersed boundary method with a directforcing strategy and the moving mesh method. Although ...
Generalized Porous Media Flow in ICFD-LS-DYNA: FSI, Free-Surface, RTM and Parachute Modeling
R. Paz, F. Del Pin, I. Caldichoury (LSTC); H. 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 ...
Head Impact Analysis Validation for Aluminium Bonnet
O. Çolpan, F. Aras (Tofas)
In recent years, vehicle manufacturers are making improvements to find more reliable solutions to pedestrian accidents. The manufacturers have to confirm these studies on some tests to carry out the requirements of international regulations. one of important these tests is head impact test. In the head impact test, one of the most important factors that affect the injury or fatality is bonnet. The subject of this article; in recent years, ...
Hierarchical Multi-Level-Optimization of Crashworthy Structures Using Automatic Generated Submodels
H. Singh, Prof. A. Schumacher (Bergische Universität Wuppertal); C. Falconi, A. Walser (Automotive Simulation Center Stuttgart); S. Trentmann, L. Benito (Iges. Für numerische Simulation); H. Müllerschön (Scale)
The optimization of large crashworthy systems like a vehicle body in a crash loaded case is a time consuming and costly process. Extensive computer simulations are required to improve the crashworthiness of such large systems using an optimization technique. The simulation time can be reduced by dividing the large system into small subsystems also known as submodels. The submodels are used in the optimization to shorten the response time. But ...
High-Dynamic Drop Test Simulation for Fiber Reinforced Plastics in Automotive Electronic Control Units
T. Zhao, D. Papathanassiou (Bosch Automotive Products)
Short fiber reinforced plastics (SFRP) are widely utilized for electronic control units (ECU) in automotive fields. Failures in plastic parts often lead to re-tooling hence unpredicted increase in cost of manpower and time. Simulation indeed can offer the chance to virtual investigation without real samples therefore can deeply contribute in early development phase. As well known anisotropic material behavior induced by non-trivial fiber ...
Hot Rolling Simulation of Aluminium Alloys using LS-DYNA
P. Simon, G. Falkinger (AMAG); S. Scheiblhofer (Leichtmetallkompetenzzentrum Ranshofen )
Aluminium and its alloys are widely used and applications of aluminium alloys can be found in all kind of industries, from packaging to transportation, from consumer electronics to architecture and lighting. In order to obtain a better understanding of the production process of aluminium alloy plates and sheets AMAG rolling GmbH strengthens the use of coupled thermo-mechanical finite element methods in combination with microstructure based user ...
Hybrid Laminated Glass: Material Characterisation and CAE Modelling
B. Feng (JaguarLandRover)
Different from standard laminated glass which is made of from soda-lime glass, hybrid laminated glass comprises layers of standard soda-lime glass, PVB and chemically toughened glass. Hybrid laminated glass has advantage of weight saving, so it has drawn great attentions to the automotive industry recently. However, its application may have impacts not only to the performances of many attributes, safety, NVH, etc., but also to the CAE ...
Hydrodynamic Drag Force Predictions for Amphibious Military Vehicles
I. Kurtoglu (FNSS Savunma Sistemleri)
Amphibious military vehicles are very important in the battle field due to their flexible operating environment. In general, amphibious military vehicles are designed for water operations in still lakes and rivers with low current speed. There are also some examples of amphibious military vehicles operating in open water environment with harsh sea state conditions. Having this operational flexibility makes the amphibious military vehicles ...
Impact of Soft Body Materials, an Experimental and Numerical Approach using a Hopkinson Tube: Application to Substitute Bird
J. Pernas-Sánchez, R. del Caurillo, J.A. Artero-Guerrero (University Carlos III of Madrid)
Aeronautic and Aerospace industries permanently seek to optimize structural components due to the high safety and reliability requirements. These improvements in the structures should withstand severe case of loads to accomplish the certification processes; traditionally the designers use experimental tests to validate it. The use of virtual testing could reduce the development times and costs but this needs reliable material models to produce ...
Improvement of Response Surface Quality for Full Car Frontal Crash Simulations by Suppressing Bifurcation using Statistical Approach
M. Okamura (JSOL)
In recent years, it has become increasingly important to take into account dispersion of product quality in automotive industry. Liability and performance has been guaranteed by adding safety margin to its target in the past. However, needs in cost reduction and trade-off of conflicting requirements do not allow manufacturers enough amount of safety margin anymore. A common way to assess robustness of the structure in full car crash is to ...
Improving LSTC’s Mulitfrontal Linear Equation Solver
R. Lucas, R. Grimes, F. Rouet, C. Weisbecker (LSTC)
Solving large sparse linear systems of equations is often the computational bottleneck for implicit calculations. LSTC is continuously improving its existing solvers, as well as looking for new technology. This talk describes improvements to the default multifrontal distributed memory linear solver used by LSTC. Changes in semiconductor technology have transformed microprocessors and their memories. In collaboration with Intel, LSTC has adapted ...
Investigating the Influence of Local Fibre Architecture in Textile Composites by the Help of a Mapping Tool
M. Vinot, M. Holzapfel (DLR); C. Liebold (DYNAmore)
Standard approaches for the modelling and simulation of composite structures rely on the homogenisation of material properties on unidirectional plies. Doing so, simulations lose the ability to precisely describe local phenomena and complex failure mechanisms. In the research campus ARENA2036, the project DigitPro (Digital Prototype) develops a method based on a closed simulation process chain to take into account potential production effects by ...
Investigation on the Dynamic Behavior of AlgoTuf 400F Steel
G. Toussaint (Defence Research and Development Canada)
In order to improve finite element simulation predictions of a dynamic event such as a blast or a ballistic impact on a structure, the dynamic behavior of the materials involved has to be investigated. The information gathered from this investigation can then be further used to choose the constitutive material model as well as identified its parameters. In this paper, the main objective is to share the findings from this investigation for ...
Isogeometric Models for Impact Analysis with LS-DYNA
M. Montanari, N. Petrinic (University of Oxford); L. Li (LSTC)
The advent of isogeometric analysis (IGA) opened new horizons for reducing design and optimisation costs. By employing the same mathematical formulation to describe CAD and simulation models, IGA integrates design and analysis into a new paradigm. Our work is part of a technology validation effort that aims to assess IGA for the analysis of impacts. Case studies of (i) wave propagation, (ii) model calibration and (iii) ballistic impact are ...
Laminated Amorphous Polymers Subjected to Low-Velocity Impact
A. Rühl, S. Kolling (TH Mittelhessen); J. Schneider (TU Darmstadt); B. Kiesewetter (Evonik Industries)
The substitution of conventional glass products by polymeric structures bears a huge weight reduction potential for the automotive and aviation industry. Against this background, a polymeric laminate consisting of poly(methyl methacrylate) (PMMA) and thermoplastic polyurethane (TPU) was investigated experimentally and numerically with regard to its impact behavior and applicability. Basic experiments with PMMA and TPU were used to identify the ...
LS-TaSC Product Status
K. Witowski (DYNAmore); W. Roux (LSTC)
The LS-TaSC Version 3.2 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. In addition, the capabilities currently under development such as designing to maximize the ...
Manufacturing Simulation as Part of the Digital Prototype
P. Böhler, J. Dittmann, D. Michaelis, P. Middendorf (Universität Stuttgart); C. Liebold (DYNAmore)
The research project Active Research Environment for the Next generation of Automobile (ARENA2036) is a long term project funded by the Federal Ministry of Education and Research Germany. Within this project four sub-projects are located. DigitPro, one of those sub-projects, deals with the development of a Digital Protoype. A closed simulation process chain is built which not only covers different simulation disciplines such as crushing or ...
Marine Accident Integrated Analysis System using Highly Advanced M&S System of FSI Analysis Technique
S. Lee, J. Lee, J. Park, T. Jung (Korea Maritime & 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 Marine Accident Integrated Analysis System (MAIAS) using highly advanced Modeling & Simulation (M&S) system of ...
Material Characterization of a 3D-Woven Carbon Fiber Preform at Macro-Scale Level for Manufacturing Process Modelling
G. Scarlat, R.Ramgulam, P. Martinsson, H. Bayraktar (Albany Engineered Composites)
The latest generation of CFM LEAP aero engines that power the Boeing 737-MAX and Airbus A320neo have their fan blades and fan-cases made out of 3D woven carbon fiber and epoxy composites. These composites are manufactured using preforms that are 3D woven and undergo a complex forming process during manufacturing prior to being injected with resin during the RTM process. The present paper showcases the work done at Albany Engineered ...
Maximizing Cluster Scalability for LS-DYNA
P. Lui, D. Cho, G. Lotto, G. Shainer (Mellanox Technologies)
High performance network interconnect is an integral component that enables all compute resources to work together. It is the key to scaling the LS-DYNA simulation in a cluster environment for both network compute and network storage to accelerate CAE simulations. The latest Mellanox InfiniBand adapters have introduced a novel high-performance and scalable architecture for high-performance clusters. This architecture was enhanced to provide ...
MDO Collision/NV/Stiffness Optimization with LS-OPT
R. Ishii (JSOL); Y. Tanaka (Toyota Auto Body); M. Nishi (Nihon Emsco); M. Takeda, (JSOL)
LS-DYNA is heavily used to analysis transient phenomenon like car crash and makes a huge achievement about physical simulation in a wide variety of industry. For the goal of LS-DYNA, gone-model , one-codeh as solution it give you, a wide variety of function has been developed at each section. Nowadays, LS-DYNA has been developed further and become possible to evaluate Frequency domain analysis and Acoustic analysis as FRF/SSD/AcousticBEM/FEM ...
Mechanical Modeling of Li-Ion Cell Crush Experiments using LS-DYNA
M. Seulin, C. Michel, V. Lapoujade (DynaS+);
Electric vehicles (EVs) and hybrid vehicles (HEVs) sales have grown spectacularly in the last few years. Safety has become an increasingly pressing issue in large-format, energy dense Li-Ion batteries used in electric and hybrid cars. The anticipation of the response to abuse conditions becomes a critical factor in designing optimized systems. Internal short circuit is one of the most dangerous scenario and has been the root cause of several ...
Modeling of a Cast Aluminium Wheel for Crash Application
Y. Leost (Fraunhofer Insitut EMI)
The modeling of wheels might have a strong influence on the vehicle response in crash simulation. The present work is about the development of a predictive cast aluminium wheel model for crash application. Coupons were directly extracted from the rim, spokes and the hub regions and experimental tensile and pressure tests were carried out to determine the material properties. The damage model GISSMO (Generalized Incremental Stress-State dependent ...
Modeling of Curing Adhesives between Jointed Steel and Aluminum Plates using MAT_277 in LS-DYNA
S. Dong (Ohio State University); A. Smith, A. Sheldon (Honda)
In this paper, a sandwich structure of two jointed plates with an adhesive layer in between is simulated. A top plate of aluminum, and bottom plate of steel are jointed with rivets. Then the plates go through the oven for paint baking, which lasts for approximately 60 minutes with oven temperature increasing in the beginning, then keeping constant, and decreasing towards the end. The difference in thermal properties between the aluminum and ...
Modelling of Ductile Polymer Model for Crash Application
Y. Ngueveu, S. Miyagano (Toyota); F.Lauro Universite de Valenciennes); R. Balieu (KTH Royal Institut of Technology)
Due to their lightweight and mechanical properties, ductile polymers are widely used in automotive industry. Those polymers play an important role during pedestrian protection performance as they are designed to absorb some of the energy induced by the collision with the pedestrian. To achieve a good and robust design fulfilling our target, CAE simulations are used. However, a mismatch between CAE results and experimental test can arise, leading ...
Modelling of Hot Rotary Kiln
D. Ramanenka, G. Gustafsson, P. Jonsen (Lulea University)
Rotary kilns are the central part in the production of many important materials, such as: cement clinkers, lime for paper production and iron-ore pellets for steel making. The main design of a rotary kiln is rather simple – consisting of a cylindrical steel casing and one or several layers of refractories in order to protect the casing from high service temperatures. The dimensions of a rotary kiln vary between some 10 to 180 m in length and 2 ...
New Features for Metal Forming in LS-DYNA
X. Zhu, L. Zang (LSTC); B. Hochholdinger (DYNAmore Swiss)
 
New Generation Modeler for LS-DYNA Material Parameter Conversion
H. Lobo, E. Strong, A. Beckwith (Matereality)
We describe a new software component that takes into consideration the unique multi-variate nature of LS-DYNA material models. Rate-dependent models require adjustment and tuning of many material parameters to fit the rate-dependent tensile properties. Drawing upon a robust back-end data model, a graphical user interface provides drag and drop capability to allow the user to perform tasks such as model extrapolation beyond tested data, modulus ...
Novel Simulation of Composite Material behavior Subjected to Hyper-Velocity Impact (HVI) and Produced Secondary Debris by using Smoothed Particle Hydrodynamics Code (SPH) Methodology in LS-DYNA
E. Giannaros, Prof. A. Kotzakolios, S. Tsantzalis, V. Kostopoulos (University of Patras); G. Campoli (ESA /ESTEC)
The escalating usage of composite materials to improve fuel efficiency while reducing the structural mass of satellites and manned spacecrafts has become high priority target to the space industry. On the other hand, high moving space debris such as old satellites, spent rocket stages and fragments from collision can devastate the composite structures producing thousand secondary debris. Therefore, the prediction of impact behavior of composites ...
Numerical and Experimental Investigation of Asymmetrical Contact Between a Steel Plate and Armor-Piercing Projectiles
T. Fras (French-German Research Institute of Saint-Louis); P. Pawlowski (Polish Academy of Sciences)
The study presents the discussion on modeling of interactions between armor-piercing (AP) projectiles and add-on perforated plates realized by the experimental investigation, numerical finite-elements simulation and the simplified modeling based on the integration of the equations of motion of a rigid projectile. It is known that relatively thin steel plates with an array of holes, i.e. perforated plate, are efficient against impacts of ...