INSIGHTS - · PDF fileABAQUS Insights Feb/March 007 INSIGHTS In this issue: ABAQUS Training Schedule and Web Seminars Letter from Scott Berkey, Vice President, Worldwide Operations

INSIGHTS February/March 2007

Fatigue Analysis at Schaeffler Group

Kidney Cooling Technology at Argonne Labs

Innovative Crashworthiness Strategy

Advanced Composites Modeling

2007 ABAQUS Users’ Conference

� ABAQUS Insights Feb/March �007

INSIGHTS

In this issue:ABAQUS Training Schedule and Web SeminarsLetter from Scott Berkey, Vice President, Worldwide OperationsABAQUS “In the News”Product UpdatesSolution Update: Powertrain Noise & VibrationStrategy Overview: Crashworthiness and Occupant SafetyCustomer Case Study: Argonne Labs Uses ABAQUS to Guide Development of Ice Slurries for Kidney Cooling Technology BriefsResearch Application: Simulating Earthquake Fault-SlipAcademic UpdateAlliances Update: Schaeffler Group Analyzes Fatigue of Roller Bearing SteelsEvents Update

ABAQUS Insights is published by

Rising Sun MiIls166 Valley Street, Providence, RI 0�909-�499Tel. +1 401 �76 4400 Fax. +1 401 �76 4408

[email protected]

www.simulia.com

Editor:Tim Webb

Associate Editor: Lisa Miller

SIMULIA Contributors:Tom Battisti, Scott Berkey, Karen Curtis, Jan Demone,

Karen Donovan (The Parker Group), Brad Heers, Asif Kahn,

David Palmer, Marc Schrank, Jon Wiening, Eric Weybrant, Helen Yu

Graphic Designer:Todd Sabelli

Copyright © Dassault Systèmes, �007, All rights reserved.The following are trademarks or registered trademarks of ABAQUS, Inc., a wholly owned subsidiary of

Dassault Systèmes: ABAQUS, ABAQUS/Standard, ABAQUS/Explicit, ABAQUS/CAE, ABAQUS for CATIA V5, and the ABAQUS logo. The 3DS logo and SIMULIA are trademarks or registered trademarks of Dassault Systèmes.

Other company, product, and service names may be trademarks or service marks of their respective owners.

ABAQUS Training ScheduleOur regional offices provide regularly scheduled training courses throughout the year. These seminars range from introductory to advanced analysis, covering specific topics and applications.

To view the worldwide training course schedule and register for a course, visit www.abaqus.com/support/sup_training_sched.html.

ABAQUS Web SeminarsValidate Turbomachinery Design with Realistic Simulation March 27 and March 29

Evaluate Realistic Behavior of Laminated CompositesApril 24 and April 26

Improve Efficiency with ABAQUS Solutions for Electronics PackagingAvailable for replay.

Improving Powertrain Noise & Vibration Analysis Available for replay.

On-Demand Web SeminarsABAQUS for CATIA V5 Version 2.4 UpdatePast web seminars are also available for replay.

To register for our free web seminars, visit www.abaqus.com/webinars.

*Training and web seminar dates are subject to change.

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3ABAQUS Insights Feb/March �007

Commitment to Delivering Customer-Driven SolutionsScott Berkey, Vice President, Worldwide Operations

During the past several months, I have had a tremendous opportunity to meet with many of our customers all over the world. Whether I was in China, France, Japan, California, Germany, or Indiana, I was amazed by the innovative use of ABAQUS to solve challenging engineering problems. I was also impressed with the forward-looking commitment that many customers are making to utilize ABAQUS knowledge capture and process automation capabilities to ensure that simulation delivers more positive impact for their business.

In 2006 several of you took the time to respond to our customer satisfaction survey. There were various suggestions for improvement such as making user-defined functions more flexible, increasing computing speed, and providing broader computer platform and operating system support. We value your suggestions and will integrate many of them as we strive for continuous improvement in all that we do.

In general I am very pleased that the overall results of the survey indicate a high level of customer satisfaction. Ninety-one percent of respondents rate our software quality as good or better than other analysis software that they have used. Eighty-six percent rate our customer support as good or better, and ninety-three percent indicate that they are highly satisfied with our development of innovative solutions. In our next issue of Insights we plan to provide a more complete report on the survey results.

In the coming year you will also hear more about our industry solution focus. In this issue of Insights we highlight the use of ABAQUS as part of a more complete solution for particular industries. This reflects the fact that our customers are increasingly implementing ABAQUS within their integrated development processes rather than as a standalone analysis application. It is also a result of working closely with our customers to develop specific workflows and precise technical capabilities that address such applications as noise and vibration (p. 7), composite materials (p. 13), crashworthiness (pp. 8–10), and electronics packaging (p. 12).

As we grow, we are dedicated to maintaining the quality of software, support, and services that you have come to expect. This means that your input, through our surveys and your participation at user meetings, is more valuable than ever. I invite you to join us in May at the international ABAQUS Users’ Conference (p. 19). This conference is an ideal opportunity for you to provide your suggestions directly to our senior management.

I would like to take this opportunity to thank each of you personally for your growing commitment to using our solutions as an integral part of your research and engineering processes. I look forward to meeting you in my travels and at the AUC in Paris.

Scott BerkeyVice President, Worldwide Operations

Software QualityGood or Better

Needs Improvement9%

91%

InnovationGood or Better

Needs Improvement7%

93%

Customer Support

Good or Better

Needs Improvement14%

86%

2006 Customer Satisfaction Survey Preliminary Results

EXECUTIVE MESSAGE

SIMULIA is Dedicated to Customer Satisfaction

4 ABAQUS Insights Feb/March �007

Design News December 2006, pages 59–62Simulating Crashworthiness at BMWIn this well-illustrated cover story, Eric Weybrant, Product Manager for SIMULIA, describes advances in ABAQUS simulation technology for crashworthiness. His article discusses new developments in material failure modeling, mesh-independent fasteners, occupant safety, and computing performance. Informative details on such topics as the Müschenborn-Sonne forming limit diagram and the use of distributing couplings are included. See coverage in this issue of Insights on pp. 8–10.

Medical Design November 2006, page 10FEA Tells How Much Ice to Cool Kidneys for SurgeryIn a case study about the development of kidney-cooling ice slurries, Ken Kasza of Argonne National Labs outlines work undertaken in partnership with the University of Chicago Medical School. The research team uses ABAQUS to model the effects of kidney cooling during surgery. “The goal,” says Kasza, “is to create a patient-specific kidney simulation that surgeons can review while planning cooling strategies for that patient’s surgery.” See coverage in this issue of Insights on p.11.

Aerospace EngineeringOctober 2006, pages 13–15A Deeper DiveContributing writer Terry Costlow surveys a host of simulation and testing tools in this article about aerospace design. In a special sidebar on composites in aerospace, Dale Berry, Director of Industry Solutions for SIMULIA, emphasizes the particular importance of analyzing composite parts for barely visible impact damage.

Mechanical EngineeringOctober 2006, pages 34–36Translation TimeIn this overview article, Associate Editor Jean Thilmany examines the “creaky and inefficient handoff between CAD and analysis.” Greg Brown, Manager of ABAQUS Interactive Products for SIMULIA, comments on the problems analysts face when they receive CAD model geometry that hasn’t been properly translated or prepared for preprocessing. See product update coverage in this issue of Insights on p. 6.

Desktop EngineeringSeptember 2006, pages 22–26FEA’s Expanding RoleDana Corporation is cited in this trends report, which explores new tools for integrating FEA into the product lifecycle. “With today’s huge file sizes, you have to have a process flow in place [that manages] how you move information from model setup to solving to postprocessing,” says Frank Popielas, Manager of Advanced Engineering for the Sealing Products Division at Dana.

Composites TechnologyOctober 2006, pages 26–30The ABCs of FEAContributing writer Jared Nelson offers a useful FEA primer for designers of composite parts. He explains the concept of virtual testing and maps out the steps involved in FEA modeling. A section of the article focusing on composites-specific FEA describes the capabilities of VCCT for ABAQUS, with information provided by Dale Berry, Director of Industry Solutions for SIMULIA. See the composites impact Technology Brief in this issue of Insights on p.13.

Share Your StoryIf you would like to share your ABAQUS success story, send an e-mail with a brief description of your application to [email protected].

ABAQUS “In the News”

Industry Press Coverage


Investigating Potential Oil Hazard of Sunken Battleship

New Director of Product Management

Steve Crowley is the new Director of Product Management for SIMULIA. Steve will be focused on capturing customer requirements and improving processes and tools for product planning, communication, and collaboration between the SIMULIA product management teams in Providence, Rhode Island, and Suresnes, France.

“We have aggressive plans to expand our product offering beyond the existing ABAQUS and CATIA Analysis applications,” stated Ken Short, VP Strategy & Marketing, SIMULIA. “Steve’s global product management experience will be invaluable as we embark on fulfilling our mission.”

“The opportunity to join SIMULIA at a time when we are developing new and scalable simulation solutions is very exciting,” said Crowley. “I look forward to working with our customers to gather requirements for our products that will support their research and PLM processes.”

Crowley has more than 20 years’ experience in planning and managing a diverse range of software products. Most recently, he was VP of Product Management and Development at Cohesia Corporation, where he was responsible for the vision, definition, and delivery of a scalable, web-based product for supply chain requirements. Prior to this he worked at SDRC as Director of Digital Mockup Software Development and as Director of Product Planning for SDRC’s I-DEAS product suite. Crowley has a B.S. and M.S. in Mechanical Engineering from the University of Cincinnati.

What happens when a fully- fueled battle ship sinks to the bottom of the ocean? How is fuel leakage managed to prevent a severe environmental incident? In an informative article, Computerworld reporter Todd Weiss tells the story of Timothy Foecke, a Metallurgist at the Maryland-based National Institute of Standards and Technology (NIST), who is using ABAQUS to answer these types of questions.

For the past two years Foecke has been examining the USS Arizona, a sunken battleship and WWII memorial that has been slowly leaking its fuel oil into Pearl Harbor for 65 years. There are growing concerns that as the hull corrodes in the salt water, the ship structure will fail and spill large quantities of the trapped oil, completely contaminating the harbor.

In cooperation with the National Park Service and the USS Arizona Preservation Project, Foecke and his colleague, Dr. Li Ma, have

been using ABAQUS to model parameters such as pressure of mud on the decaying hull, crust of barnacles and vegetation, water currents, changing pressure, and the corrosion of hull plates. Using the software, he is able to evaluate possible oil leak scenarios and make salvage recommendations for the preservation of the ship and the protection of the harbor.

In addition, Foecke hopes that by sharing his research methods with other scientists, they will be able to evaluate hundreds of existing shipwrecks and protect our waterways from potential environmental threats well into the future.

For More InformationView the complete article from the Computerworld December 7, 2006 issue online at www.abaqus.com/insights.

Dr. Robert L. Taylor, an internationally recognized scholar and researcher in mechanics of solids, computational mechanics, FEA methods, and FEA software, has been appointed as Corporate Fellow within the SIMULIA brand of Dassault Systèmes. In this new role he will perform research to advance technology and methods for ABAQUS FEA and multiphysics software.

“There is a great tradition of research and development for advancing FEA methods and solvers within the ABAQUS product family,” Dr.Taylor stated. “While the simulation industry has progressed significantly over the years, there is still work to be done to account for new materials and applications. I look forward to collaborating with the largest R&D team in the world dedicated to developing new and improved FEA solutions.”

Dr. Taylor has authored or coauthored more than 200 scientific publications including the The Finite Element Method with O.C. Zienkiewicz. He has received numerous awards, including the Daniel C. Drucker Medal (2005) from the American Society of Mechanical Engineering and the Gauss-Newton Congress Medal (2002) from the International Association for Computational Mechanics. He is a graduate of the Department of Civil Engineering at the University of California, Berkeley (M.S. 1958, Ph.D. 1963), where he was also a member of the Structural Engineering, Mechanics, and Materials faculty from 1963–1994. In 1994 he became the T. Y. and Margaret Lin Emeritus Professor of Engineering and Professor of the UC Berkeley graduate school.

ABAQUS “In the News”

The USS Arizona National Memorial located in Pearl Harbor.

ABAQUS results of oil-induced stresses on a section of the ship’s hull. (Model developed by Dr. Li Ma and provided courtesy of the National Institute of Standards and Technology.)

New Corporate Fellow


With ABAQUS for CATIA V5 Version �.4, engineers can simulate nonlinear load cases, such as the sag of a car door as it swings on its hinges. The model pictured above includes shell, beam, and solid components fastened together using a combination of spot welds, seam welds, and mechanisms.

PRODUCT UPDATES

With the release of ABAQUS for CATIA V5 Version 2.4, several advanced ABAQUS capabilities are available from within the CATIA V5 environment, including explicit dynamic analysis, self-contact, submodeling, and cyclic symmetry. The tight integration between ABAQUS and CATIA V5 allows product design engineers and expert analysts to collaborate by using the same models and FEA methods, ensuring analysis repeatability and accuracy. The software is available for CATIA V5 R16 and CATIA V5 R17.

Simulation AdvancementsDynamic simulation based on ABAQUS/Explicit is well suited for large models with relatively short response times and for modeling extremely discontinuous events, such as impact. This new capability enables the definition of very general contact conditions, including contact between many or all regions of a model with a single interaction definition.Self-contact modeling simulates surface folding, which is typically the result of large deformation in a model, such as a complex rubber seal that folds over on itself. This new capability allows users to easily define self-contact for selected surfaces. Submodeling enables users to target regions of interest for detailed stress analysis. This makes it easy to apply a refined mesh and boundary conditions in both mechanical and thermal steps to obtain accurate, detailed results in a local region. Cyclic symmetry modeling improves analysis efficiency and reduces model size. When analyzing a body whose geometry, loads, prescribed conditions, and response are symmetric about an axis of revolution, users can simply model a repeating sector of the body and set fastened pairs to define the sector boundaries; the software simulates the rest of the unmodeled body.

For More InformationVisit www.abaqus.com/AFC_V5.

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Today’s computer engineering environment requires maintaining relationships between CAD models and analysis models during the design iteration. This process has often required time-consuming, manual modifications of the analysis model to evaluate the most current design. To solve this problem for Pro/ENGINEER users, ABAQUS Version 6.6 Extended Functionality (EF) delivers a powerful solution for associative geometry export from Pro/ENGINEER to ABAQUS/CAE.

This new associative interface is enabled through a direct connection that maintains the relationship between the CAD assembly and the CAE assembly. It allows the user to transfer geometry, including assembly attributes, names, colors, etc., from Pro/ENGINEER to ABAQUS/CAE sessions. Using the “Open in ABAQUS/CAE” menu inside Pro/ENGINEER, an entire assembly can be transferred to ABAQUS/CAE with a single mouse click. The user can then continue to modify the model in the CAD system and use the connection to update the model quickly in ABAQUS/CAE. In addition to modified parts, any changes that are made to the position or state of instances in the Pro/ENGINEER assembly are also updated in ABAQUS/CAE. Features such as loads, boundary conditions, sets, and surfaces that are created in ABAQUS/CAE are updated automatically when a modified model is re-imported to Pro/ENGINEER.

“The Pro/ENGINEER Associative Interface for ABAQUS/CAE allows engineers to be more productive while iterating from CAD to FEA,” stated Jerome Montgomery of Siemens Power Generation. “Loads and boundary conditions are retained between design changes, and the updates are handled efficiently through an

intelligent mechanism that is a real time-saver.”

The interface also offers great flexibility in how geometry updates are transmitted. The CAD connection can be reestablished whenever an update is needed or it can be retained during an entire ABAQUS/CAE session.

In addition, the two software products do not need to be running simultaneously or on the same machine to take advantage of the interface. The user can manually write out the assembly files from Pro/ENGINEER and subsequently import them into ABAQUS/CAE to retain associativity.

The Pro/ENGINEER Associative Interface is an add-on for ABAQUS/CAE. It is available on the Windows/x86-32 platform and includes the existing Elysium translator for Pro/ENGINEER.

Upcoming releases of ABAQUS/CAE will offer associative interfaces for additional CAD systems such as CATIA V5, SolidWorks, and others.

For More Information Visit www.abaqus.com/support/sup_geometry_import.html.

ABAQUS for CATIA V5 Version 2.4 Extends Realistic Simulation Capabilities

ABAQUS Associative Interface for Pro/ENGINEER

ABAQUS Associative Interface for Pro/ENGINEER


Improving Powertrain Noise & Vibration Analysis

Quiet engines and transmissions are important to both the automobile and heavy-duty-truck markets. A noisy engine can compromise safety, reliability, and engine life. In addition to being a major source of customer quality complaints, powertrain noise and vibration (N&V) issues are subject to growing levels of government regulation. Often what seems to be a small issue with a minor part or connection actually impacts the performance of the entire vehicle. Therefore it is critical for powertrain manufacturers to leverage state-of-the-art design analysis tools to identify potential N&V problems before manufacturing and mass production.

A Unified FEA EnvironmentABAQUS is currently used at several powertrain manufacturers and suppliers. Until now it has been used primarily for thermal cycling, assembly, structural durability, and other nonlinear analyses. Improvements to existing ABAQUS capabilities as well as new features specifically for N&V enable powertrain manufacturers to leverage the software beyond stress and durability applications to encompass N&V workflows.

Well-known ABAQUS features such as contact, nonlinear materials, gasket elements, bolt pre-tensions, and thermal-structural effects can be incorporated as preexisting states for N&V analysis. This Unified FEA approach not only provides unique opportunities for collaboration across disciplines but also provides substantial improvements in efficiency and accuracy of the N&V analysis in comparison to multi-vendor solutions.

Efficient Modeling and AnalysisABAQUS enables efficient modeling of powertrain assemblies. Advanced joining features such as gaskets, bolts, and tied contact can be used to accurately model the complex connections found in powertrain systems. Advanced mechanics features allow users to easily incorporate static stiffness by using pre-loaded configurations

of gaskets and grommets to readily account for contact configurations in linear dynamics procedures.

ABAQUS/CAE enables knowledge capture and process automation, allowing validated simulation methods to be deployed across design and engineering teams. This ensures that consistent, repeatable processes are used which, in turn, improves simulation accuracy and reduces the time required to validate N&V performance.

Expanding on the existing ABAQUS Lanczos eigensolver and specific N&V features, ABAQUS/AMS is a new add-on for natural frequency extraction. It provides significant performance gains for models with large numbers of eigenvalues. Models of several million degrees of freedom and hundreds of modes can be solved for frequency response in minutes or hours, rather than days. Benchmarks indicate that powertrain N&V problems can run from 10 to 25 times faster using ABAQUS/AMS

compared to alternative methods.

Postprocessing features are critical when it comes to powertrain noise and vibration analyses. ABAQUS/CAE includes scripting capabilities and specific noise and vibration postprocessing tools that allow efficient postprocessing across networks. The network ODB connector enables postprocessing of remote files on a local PC. It eliminates unnecessary file transfer and translation of large output data sets, which are generally required by other solvers and postprocessors.

Bottomline BenefitsABAQUS provides all of the needed mechanics and solver performance to readily include nonlinear effects to address powertrain noise and vibration concerns. Based on customer implementation and feedback, the ABAQUS solution provides more efficient throughput than existing linear dynamic methods. This is due, in part, to the Unified FEA environment and the performance improvements in ABAQUS/AMS, which enable engine manufacturers to achieve accurate N&V results in less time than previously possible. In addition, powertrain N&V workflows and productivity improvements in ABAQUS ensure that customers will continue to accelerate N&V analysis and validation of complete powertrain performance with confidence.

For More InformationDownload a replay of our Powertrain Noise and Vibration Webinar at www.abaqus.com/webinars.

SOLUTION UPDATE

Without Gasket Viscoelasticity

With Gasket Viscoelasticity

The new Automatic Multi-level Substructuring (AMS) add-on in ABAQUS Version 6.6, rapidly calculates hundreds or thousands of natural frequencies. Velocity contours for a response load case are shown in this engine simulation. The results are useful in assessing potential engine noise. (Model courtesy of General Motors.)

ABAQUS enables engineers to apply nonlinear materials and damping for more realistic frequency response results. The model on the right shows higher fidelity results by taking into account viscoelastic properties of the gasket. (Model courtesy of Dana Corporation.)


Innovative Solutions for Crashworthiness SimulationEric Weybrant, Product Manager of ABAQUS/Explicit, SIMULIA

Simulating crashworthiness and occupant safety is one of the most important challenges for today’s engineering community. The physical phenomena that constitute a vehicle crash are extremely complex and the timeframe of the event is brief. Material deformation occurs in a split second with life-or-death consequences. A physical crash test can happen only once, but a valid crash model enables engineers to run hundreds of simulations at a fraction of the time and cost.

The intent of crashworthiness simulation is to model, as realistically as possible, how parts and assemblies crush, buckle, twist, shear, stretch, and tear. With advances in virtual crash test dummies, it is also possible to accurately simulate occupant safety features, including restraints and airbags. New technologies for crashworthiness simulation continue to evolve through collaboration with our customers, such as BMW Group, as well as through advances in high-performance computing. The simulation tools we have developed offer highly realistic predictions of the physics involved in a crash scenario and contribute enormously to improving vehicle integrity and passenger safety.

Material Failure Simulation Automotive manufacturers are exploring the potential of new structural materials such as aluminum and magnesium alloys and high-strength steels to reduce vehicle weight and improve crashworthiness. Understanding how these ductile materials fail during crash-loading conditions is a significant challenge.

Experimental studies show that metal sheets and thin-walled extrusions made of aluminum alloys may undergo ductile failure due to nucleation, growth, and coalescence of voids in the material. Cracks within shear bands may cause shear failure. Other failures are caused by localized instabilities. ABAQUS provides a general and robust framework for simulating such material failure.

During a crashworthiness simulation, the material stiffness is degraded progressively after damage initiation, according to the specified damage evolution response. Using ABAQUS, engineers can specify one or more damage-initiation criteria, including ductile, shear, forming limit diagram, Müschenborn-Sonne forming limit diagram, and Marciniak-Kuczynski criteria.

The traditional forming limit diagram determines the formability of sheet metal using data gathered from experimental tests. At deformation levels outside the forming limit, the material will likely exhibit failure such as necking or tearing. At deformation levels inside the limit, the material should not fail. BMW researchers determined that the Müschenborn-Sonne forming limit diagram criteria would be particularly useful for predicting material necking for their applications. The advantage of using the Müschenborn-Sonne forming limit diagram is that it takes into account the effects of the deformation path on the limit strains of sheet metals, whereas the traditional forming limit diagram is valid only for linear strain paths.

With ABAQUS, crash analysts can easily and accurately incorporate manufacturing effects into their simulations. By capturing strain that actually exists in the sheet metal before a crash occurs, the simulation is able to better reflect physical reality (Figures 1a–d). The damage framework in ABAQUS is applicable across a wide range of industries. For example, it can also be used in a manufacturing setting to simulate metal cutting.

Figure 1d: ABAQUS simulation results match the experimental data well. Modeling progressive damage and failure is essential to capturing the overall deformation behavior of materials.

STRATEGY OVERVIEW

Figure 1b: Final deformed shape of the meshed model.

Figure 1c: Deformed shape of the aluminum extrusion after the quasi-static three-point bending test (Hooputra et al., �004).

Figure 1a: Configuration for simulating a quasi-static three-point bending test of a thin-wall aluminum extrusion. The material is extruded aluminum alloy EN AW-7108 T6.

Rigid punch

Double-chamberedaluminum extrusion

H=68

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350

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Rigid supports


Mesh-Independent FastenersAutomotive assemblies contain thousands of spot welds. The manner in which spot welds undergo damage and failure during a crash can influence a vehicle’s structural integrity and, thus, is of great interest to automotive manufacturers. One of the most useful tools for crashworthiness simulation in ABAQUS is a mesh-independent fastener for spot welds (Figure 2).

In collaboration with customers, fastener technology in ABAQUS has evolved significantly. A fastener is a computationally efficient one-dimensional idealization that simulates the behavior of a “point-to-point” connection between two or more surfaces. A typical fastener joining two surfaces consists of a connector element plus two constraints called distributing couplings that identify the connecting surfaces. Engineers can draw from the extensive library of kinematic and constitutive behaviors that are available with our connector elements to assemble any type of fastener they can imagine. Deformable spotwelds are normally modeled using a bushing-type connection to describe the kinematics and either elasticity or rigid plasticity with damage and failure to describe the constitutive response.

Key to making the fastener mesh independent is the ability of distributing couplings to “smear” the connection across a region of FE mesh (Figure 3). Traditionally, each fastener would be identified with a specific node location, so all the spot-weld locations would have to be redefined whenever the model was remeshed. Mesh-independent fasteners contribute to modeling efficiency and save a great deal of time for engineers in many industries. For example, they are used widely in the aerospace industry to simulate rivets.

Marc Schrank Appointed Director, Crashworthiness and Occupant Safety StrategyA well-known ABAQUS veteran, Marc Schrank has recently transitioned roles within the company from leading

the Product Management group to directing our strategy for crashworthiness and occupant safety. While in Product Management Marc provided an essential link between our valued customers and our talented Development organization, resulting in each ABAQUS release containing features and enhancements that addressed a wide range of applications for a large, multi-industry user base. His new position will extend and strengthen that link, with a focus on those customers across various industries who have crashworthiness and occupant safety needs.

“This field is evolving rapidly,” stated Ken Short, VP of Strategy and Marketing. “Due to Marc’s ongoing involvement with many of our customers in defining crashworthiness simulation requirements, he is the best qualified person to direct our product strategy in this area.”

“It is a privilege to work closely with customers to improve our capabilities and increase our influence in the crash simulation market,” said Marc. “By dedicating additional resources to crashworthiness, we will ensure that our simulation solutions are addressing our customers’ specific needs.”

The crashworthiness strategy will leverage the SIMULIA partner ecosystem, which includes independent software vendors, computer platform suppliers, crash dummy developers, crash barrier manufacturers, and material testing organizations. In addition, Marc will monitor and participate in the extended community of crash researchers and regulatory organizations.

Figure 2: Simulated crushing of a spot welded tube showing the influence of fasteners on predicted deformation.

(Story continued on page 10)

STRATEGY OVERVIEW

Fastenerattachment

points

Multiplemeshedsurfaces

Radius of influence for the distributing coupling

Figure 3: A schematic shows how ABAQUS distributing couplings allow mesh-independent fasteners to connect to a region of meshed surface rather than to specific node locations.


The impactor is modeled as a rigid body with a mass of 7.2 kg and an initial velocity of 4500 mm/s toward the deploying airbag. The results of the simulation demonstrated close correlation with physical tests.

Leveraging High-Performance ComputingRecent releases of ABAQUS have improved parallel computing speed by using the domain decomposition method. This process divides the simulation model into separate domains and runs each domain on a different CPU. Where domains connect, there is an exchange of information to ensure consistent computational order. Ideally the model is decomposed so every CPU is doing approximately the same amount of work.

Crash simulation involves significant buckling behavior. Slight numerical differences can arise from the order in which information is exchanged between domains. This can lead to noticeable inconsistencies in results when the same model is run using different numbers of domains. Our implementation of parallel computing takes extra steps to minimize these effects and to provide repeatable results. With repeatability comes confidence that a simulation is accurate.

On the HorizonThe crashworthiness simulation solutions from SIMULIA will continue to evolve in response to design trends and regulatory demands. As automotive manufacturers investigate the benefits of using structural adhesives to join assemblies, we are enhancing ABAQUS capabilities such as cohesive elements that support the modeling of adhesive joint deformation and failure where these bonded parts interface. We also support many innovative applications for automotive composites and are currently evaluating several composite failure models for crash analysis. Our commitment of working closely with customers ensures the development of innovative solutions that improve the efficiency of simulation workflows. In the crashworthiness industry such responsiveness and technological excellence not only save time and money, these qualities also improve passenger safety.

For More InformationVisit www.abaqus.com/solutions.

Occupant SafetyTo predict what will happen to vehicle passengers during a crash, engineering analysts model the interaction of crash dummies with automotive seats, seatbelt restraint systems, and supplemental airbags. In ABAQUS the seatbelt restraint system is modeled using a series of specific connector elements. These are one-dimensional idealizations that represent the particular kinematics of connection points in the restraint system.

One such connector element is a slipring, which allows a line or cable to change its direction of travel as though it were moving around a pulley. The special element enables simulating the behavior of a seatbelt interacting with a dummy model during a crash scenario. Loading from a displaced dummy model causes the belt material to flow and stretch across attachments (Figure 4). Different connectors are used to model the behavior of the seatbelt retractor device and of the pretensioner.

In ABAQUS the modeling of airbag supplemental restraints is based on the concept of surface-based fluid cavities, a technique that is also used in the manufacturing industry to model the blow molding process. The surface of the airbag structure is defined with regular finite elements. The fluid (gas) inside the bag is not meshed. It is defined by a constant pressure that propagates from an inflator and is felt instantaneously throughout the airbag. As the simulation progresses, deformation of the fluid-filled structure is coupled to the pressure of the contained fluid on the cavity boundary.

Like many FEA models, airbag models are validated by comparing simulation results with experimental data. To simulate an impact test on a deployed side-curtain airbag (Figure 4), the airbag is divided into 18 chambers to approximate the nonuniform distribution of gases and the pressure gradients observed during unfolding. Each chamber is modeled as a surface-based fluid cavity. The airbag skin is represented by membrane elements and uses a special fabric material model available in ABAQUS.

Figure 4: Simulated impactor test of a side-curtain airbag deployment represents human head mass and velocity typically observed in vehicle side impacts. (Model courtesy Autoliv GmbH.)

Figure 3: An initial velocity for the dummy model is set at approximately 45 miles per hour while the attachment points of the seat and the seatbelt are held fixed on the car frame. The slipring connector allows seatbelt behavior to be simulated in a vehicle that comes to an abrupt stop.

slipring

slipring

slipring

slipringslipring

slipringretractor and hinge

retractor and hinge

slipring

slipringslipring

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slipring

STRATEGY OVERVIEW

Innovative Solutions for Crashworthiness Simulation (cont’d.)


Argonne Uses ABAQUS to Guide Development and Application of Ice Slurries for Kidney CoolingSurgeons who perform open-cavity kidney operations use hand-packed ice around the organs to delay organ damage and extend surgical times. However, doctors performing less-invasive laparoscopic surgeries do not have this option. They must clamp off major blood vessels prior to surgery, decreasing the time available before tissue damage from lack of oxygen develops. To date, many proposed cooling variations have not worked well for laparoscopic surgery. Traditional medical ice slurry does not flow reliably and clogs in surgical tubing. Surgery has thus been limited to around 30 minutes and can address only simpler scenarios, such as small tumors. An effective cooling solution would enable doctors to extend surgery times and tackle more complex problems in a less-invasive way, improving patient recovery time as well.

Innovative Ice SlurriesArgonne Labs and the University of Chicago Medical School have been developing new ice slurry cooling solutions. “We’ve worked on these slurries for more than ten years, first for industrial application and then, starting six years ago, with emergency room physicians, nephrologists, cardiologists, neurologists, and brain specialists,” said Ken Kasza (Ph.D.), a senior mechanical engineer in the Energy Technology Division at Argonne. “With their help, we’ve been able to create a number of promising slurry formulations and medical applications.”

The newly developed slurries use a saline carrier solution that is biologically compatible and is much like the drip bag saline already in common medical use. Use of this coolant can extend surgical time to more than 90 minutes. One of their patented micro-particle slurries is pumped effectively through small surgical tubing. During testing it has cooled kidneys from 37˚C to below 15˚C in less than 10 minutes.

Simulation Validates EfficacyAn important task in developing and validating the efficacy of slurry cooling was simulating the cooling of a kidney using ABAQUS. “We use numerical simulation to guide development and prove out all of our medical cooling projects, which also involve cooling other organs,” Kasza said.

To simulate cooling of the tissue, Kasza and his colleague, F. C. Chang, incorporated the commonly used Pennes bio-heat transfer equation into ABAQUS. This equation enables modeling of tissue metabolism and perfusion thermal behavior. They created a three-dimensional mesh model for a kidney using scanned images

of thirty-six two-dimensional parallel image slices of kidneys from the National Institutes of Health Human Image databanks . They then created a three-dimensional model and mesh from the scanned slices. The finished computational mesh contained 80,426 tetrahedral heat transfer elements.

The researchers performed two kidney cooling simulations using kidney temperature data from two tests involving laparoscopic and transperitoneal surgical access to a kidney. The initial kidney temperature was 37˚C for both tests. The tests performed involved completely covering the kidney with ice slurry (applied immediately after blood vessel clamp-off). They were simulated by setting the mesh boundary temperature to 0˚C and the metabolic/perfusion rates to 0.

ResultsSimulation results were compared to physical data for cooling during minimally invasive surgeries. For all tests, the predictions agreed well with the physical measurements during the cool-down process with clamped blood vessels. They also agreed reasonably well during warmup when vessels are unclamped, perfusion resumes, and metabolic rate becomes active again.

“A long-term goal of this research is to create a patient-specific kidney simulation that surgeons can use to plan the cooling strategy for their surgery,” Kasza said. To reach this goal, Argonne is currently creating higher-resolution kidney models from CT and MRI scans to account for major blood vessels, voids, and any tumors within the kidneys of individual patients. Argonne is also expanding its development of ice slurry cooling and ABAQUS simulations to other organs where cooling provides protection from ischemia during surgery or medical emergencies such as cardiac arrest.

For More InformationLearn more about using ABAQUS for biomedical solutions at www.abaqus.com/medical.

Laparoscopic surgery view of kidney prior to delivery of slurry (left) and kidney covered with slurry from delivery tube M (right). (Photos were captured from a video monitor by Argonne at U.C.)

Meshed 3-D ABAQUS model of a kidney used to perform cooling simulations. (Model courtesy of Argonne Labs.)

CUSTOMER CASE STUDY

Comparison between ABAQUS predicted kidney cooling temperatureand Test 1 data obtained from experiments conducted at the University of Chicago under minimally invasive laparoscopic surgery conditions.

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TECHNOLOGY BRIEF

Lead solders, such as the popular tin-lead variety, have been used in the electronics industry for the past 50 years; thus, their long-term reliability is well understood. However, lead and its compounds are highly toxic and the disposal of these materials into the environment has become an issue of great importance. In conjunction with legislation requiring the eventual use of lead-free materials, the electronics industry is working towards reducing the amount of lead in end-user equipment. This transition requires new finite element material models to evaluate the reliability of lead-free solders.

During their operation, electronic components are subject to a large number of thermal cycles. Mismatch between the thermal expansion behaviors of the various materials may induce severe stresses that are high enough to cause plasticity and creep. Solder balls are at particular risk because they experience temperatures that reach above half of the solder’s melting point. At such temperatures, the solder creeps; after a number of thermal cycles, the accumulation of large inelastic strains may lead to failure of the solder joints. Therefore, the creep analysis of solder balls under cyclic thermal loading is an important part of the design phase.

ABAQUS Version 6.6 offers several creep models that can be used by the electronics industry for analyzing the performance of lead-free solders. The hyperbolic-sine model is available as a regular feature, and the modified Anand and double-power models are freely available as user subroutines. In addition, the scripting and GUI toolkit interfaces allow the capabilities of ABAQUS/CAE to be customized to automate specific tasks associated with the development of certain classes of models. Process capture and automation also allow non-expert users to run pre-packaged analyses easily.

Simulating CreepThe Ball-Grid-Array (BGA) model, analyzed in a new ABAQUS Technology Brief online, was created using a custom application in ABAQUS/CAE that was developed at Worley Parsons PTE Limited, Singapore (Figure 1).

The process of building the BGA model was captured in several icons; e.g., the Model icon, the Material icon, the Load icon, etc. This allows users to enter parameters into a form to make modifications to the model. For example, only the dimensions for a BGA model need to be specified in the Model dialog box, and then the model is built and meshed automatically.

In this BGA model, 36 solder balls connect the silicon die and the substrate with underfill material used in the space surrounding the solder balls (Figure 2). All components except the substrate are encapsulated in the mold. The bottom of the substrate is fixed, and no other direct mechanical loading is applied.

To simplify this analysis example, it is assumed that the entire model is subject to uniform thermal cycling. In a more detailed analysis, the temperature field could be obtained from a previous heat-transfer analysis or the simulation could be carried out as a fully-coupled temperature-displacement analysis.

Results & ConclusionThe distribution of equivalent creep strain (CEEQ) at the end of the analysis showed thermal expansion mismatch between the solder and the surrounding materials resulting in high creep strain near the top and bottom surfaces of the solders. In addition, the creep strain in solders at the perimeter of the array is higher than that near the center. The solders with the highest creep strains are those at the four corners, suggesting that these are the critical joints for the simulated device (Figure 3).

The fast-growing application of lead-free materials in the electronics industry has brought new challenges with regard to the simulation of creep behavior. The advanced features of ABAQUS including a large material library, extensive nonlinear analysis capabilities, and thermal-mechanical coupling, make it a powerful design tool for the electronics industry.

Figure 3: Equivalent creep strain at end of loading history.

Figure �: Schematic section view of the BGA Model.

Silicon Die Underfill

Solder Balls

Mold

Substrate

Creep Analysis of Lead-Free Solders Undergoing Thermal Loading

Figure 1: Ball Grid Analysis (BGA) model.

For More InformationDownload the Tech Brief from the electronics section atwww.abaqus.com/solutions/tech_briefs.html.

Features of ABAQUS for Electronics Packaging Simulation

Extensive material library that includes commonly used

creep models for lead-free solders Sequentially or fully coupled thermal-mechanical analysis Geometrically nonlinear analysis Scripting interface for process automation

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TECHNOLOGY BRIEF

separate analyses were run for initial velocities of 150, 180, and 250 m/s; the results were compared to the published work of Kasano.

ResultsThe comparison between the ABAQUS analysis and the experimental data showed very good agreement for all impact velocities (Figure 2).

A second area of interest in ballistic impact analysis is composite material damage and failure. Significant damage occurred both locally as the ball penetrated, and globally due to propagation and reflection of stress waves through the material. The liberated material was ejected both from the back face as well as from the interior of the plate (Figure 3).

ConclusionSince there are many failure modes in composite materials, accurate predictions of impact behavior require the use of material models that represent multiple physical mechanisms. The user-defined material subroutine(VUMAT)capability in ABAQUS/Explicit enables analysts to incorporate the most applicable damage and failure model for the problem at hand. General, “automatic” contact capabilities facilitate the complex analyses that composite materials require, making ABAQUS a natural choice for composite modeling and simulation.

For More InformationDownload the Tech Brief from the aerospace section atwww.abaqus.com/solutions/tech_briefs.html.

Projectile Impact on a Carbon Fiber Reinforced Plate

Figure 1: Geometry used for composite impact simulation with through thickness mesh detail.

Figure 3: Bottom view of composite plate damage after penetration by steel ball.

Figure �: Comparison of ABAQUS simulation results to the experimental data of Kasano.

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Composite materials offer significant design advantages in many industries. For example, in the aerospace and automotive industries composites allow the design of lightweight, yet high strength vehicles. Such designs increase efficiency, speed, and dynamic response while minimizing fuel consumption. However, the complex material behavior of composites makes the analysis of these structures a significant challenge, particularly in a high-speed impact or crash event. The advanced composites modeling and simulation capabilities of ABAQUS/Explicit make the analysis of these challenging materials possible and allow accurate prediction of ballistic limit, damage, and failure.

Simulating ImpactA newly available ABAQUS Technology Brief describes the simulation of an orthotropic composite plate undergoing impact by a steel ball projectile. The projectile was a 5 mm, cold-rolled steel ball with an initial velocity specified in a direction normal to the plane of the plate. Both the projectile and the plate were meshed with first-order, reduced-integration, solid continuum elements. The composite ply lay-up was a simple orthotropic design. Eighteen ply layers of 0.2 mm thickness were modeled individually using solid continuum elements (Figure 1).

The plate geometry was partitioned to include a central “target” location that allowed a finer mesh to be applied to the local impact zone and a coarser mesh to be applied at the outer edges of the plate using the swept meshing capability in ABAQUS/CAE. To allow the projectile to interact with the internal plate material, a surface was defined that included all interior faces of the plate mesh, and then this surface was included in the general contact definition.

The behavior of the unidirectional carbon fiber material was modeled with a user-defined material subroutine(VUMAT) which makes it possible to utilize the most appropriate damage model for a particular application. The Hashin damage criterion was specified for the fiber failure modes, while the Puck criterion was used for the matrix failure modes.

The residual velocity of the projectile after exiting the back side of the plate is of primary interest in this type of analysis. Three

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Mesh construction is a key consideration in the course of building a finite element model. Specifically, the analyst must consider the type of elements and the density of the mesh and apply more refinement

in critical regions. These considerations need to be balanced with the desire to minimize analysis cost in terms of preprocessing effort, analysis run time, and computer resources.

The new adaptive remeshing feature in ABAQUS Version 6.6 allows ABAQUS/CAE and ABAQUS/Standard to work together automatically, in an iterative fashion, to determine an optimal mesh. This time-saving capability enables you to obtain a solution that satisfies discretization of error indicator targets while minimizing the number of elements and, therefore, the cost.

To give you more details on the adaptive remeshing technique, an ABAQUS Technology Brief is available online that demonstrates the sequentially coupled thermal-structural analysis of the Shippingport nuclear reactor. This reactor was the

first commercial nuclear power generator in the United States. In operation between 1957 and 1982, it was a pressurized water reactor, meaning the primary coolant loop used water under high pressure to transfer heat from the reactor core.

Leveraging Adaptive Remeshing In this example a simplified form of the complete reactor vessel assembly was created in ABAQUS/CAE. It included the vessel, the closure head, the studs, the nuts, and the washers. The structure contained several complex features, including openings in the vessel, rapid thickness transitions, fillets, and small radii in the closure region.

A short and rapid temperature change is considered to be a severe load case for a nuclear reactor. This simulation considered the effect of a thermal transient in the primary coolant loop, specifically a 30°F decrease in the interior water temperature over a 45-second period. The reactor vessel assembly was also subjected to a nominal operating pressure of 2 × 103 psi.

To simulate this effect, a sequentially coupled thermal-structural analysis was carried out to analyze the response of the pressurized water reactor to the thermal transient. The heat transfer analysis was

TECHNOLOGY BRIEF

Figure 1: ABAQUS/CAE Model of the Shippingport nuclear reactor.

conducted first, and the temperature results were read into the stress analysis as part of the loading. Adaptive remeshing was employed in both the heat transfer analysis and the stress analysis (Figure 2).

During the thermal analysis, the adaptivity process was completed after the second remeshing iteration because all remeshing rules were satisfied. In the second iteration, significant improvement in the temperature results was observed near the bolt flanges (Figure3). The stress increased quickly during the applied thermal transient and became nearly constant at the end of the step. Lower stresses were reported with a finer mesh. To emphasize the effectiveness of the adaptive remeshing, the analysis was rerun with the original mesh refined manually by simply halving the mesh seed sizes. As was predicted, the mesh was not refined as effectively as it was with adaptive remeshing.

During the structural analysis step, the adaptivity process was also run with two remeshing iterations where error indicators were calculated for a manually refined mesh. Adaptive remeshing improved the accuracy of the results more effectively than uniform refinement, especially in regions where high stresses were focused in small areas such as in the stud bolts.

ConclusionBy using the new adaptive remeshing capability available in ABAQUS Version 6.6, the quality of your simulation results can be improved without prior knowledge of how refined the mesh must be to obtain accurate results. ABAQUS/CAE and ABAQUS/Standard work together efficiently to create a mesh that simultaneously satisfies your user-defined error targets while minimizing the number of required elements.

For More InformationDownload the Tech Brief from the manufacturing section atwww.abaqus.com/solutions/tech_briefs.html.

Figure �: A 45° cut of the vessel near the outlet nozzle created in the first (left) and second (right) remeshing iterations during the structural analysis.

Figure 3: Mises stress in the outlet nozzle from the mesh created in the first (left) and second (right) remeshing iterations.

Coupled Thermal-Structural Analysis of the Shippingport Nuclear Reactor Using Adaptive Remeshing in ABAQUS/CAE


According to the Theory of Plate Tectonics, the Indo-Australia Plate and overriding Eurasia Plate are converging at a rate of about 6 cm/yr. Stresses caused by this convergence accumulate along the fault separating the plates until the stresses destabilize and rupture the fault. This relatively instantaneous fault-slip event is an earthquake. The M9 Sumatra-Andaman Earthquake of December 26, 2004 is one of the largest in recorded history. The event ruptured a 1200-kilometer-long and 150-km-wide portion of the boundary separating these plates. Although the M9 earthquake was destructive in itself, the seafloor deformation caused by it triggered a tsunami that was far more devastating.

While the colossal forces behind earthquakes are beyond our control, we can improve our understanding of them and attempt to minimize their impact on society. In the name of computational simplicity, the vast majority of geophysicists use simplified analytical solutions for inverse analyses of earthquake deformation, which poorly represent the complex structure of the deformational system. However, using ABAQUS it is possible to bypass these unrealistic simplifications and readily integrate the powerful capabilities of finite element models in inverse analyses. Such modeling provides the link between directly observable surface deformation and the inaccessible fault-slip, which is what we need to better understand.

ABAQUS is uniquely capable of simulating earthquake deformation for a three-dimensional problem domain having a distribution of material properties appropriate for a system of converging tectonic plates. The array of analysis and element types available in ABAQUS allows us to simulate the elastic response of the earthquake as well as the transient post-earthquake process with a

single model. No other finite element package allows for seamless simulations of the earthquake and coupled post-earthquake processes. The preliminary results shown below are part of a project recently funded by the NASA New Investigator Program.

This project used ABAQUS forInverse models to estimate the fault-slip characteristics of the M9 Sumatra-Andaman earthquake based on observed GPS measurements.Forward models, driven by the estimated fault-slip, to predict the seafloor deformation that will serve as the initial conditions for tsunami propagation and run-up models.

Author and ResearcherDr. Timothy Masterlark is an Assistant Professor of Geodynamics at the University of Alabama, Tuscaloosa. He received his B.S. from the University of Wisconsin-Eau Clair in 1994 and his M.S. and Ph.D. from the University of Wisconsin-Madison in 1996 and 2000, respectively. His current research includes earthquake and volcano deformation mechanics, stress coupling and earthquake prediction, forward and inverse modeling, geophysical applications of remote sensing data, and visualization.

For More InformationContact Dr. Masterlark at [email protected] visit www.geo.ua.edu/Masterlark/masterlark1.htm.

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The dark shaded region outlined in yellow is the surface projection of the plate boundary region that ruptured during the earthquake. Observed GPS measurements (red arrows) show the horizontal movement of the Eurasian Plate, with respect to the Indo-Australian Plate, as a result of the earthquake. Forward model predictions (yellow arrows) are extracted from an ABAQUS model loaded with the estimated fault-slip characteristics inverted from the GPS measurements.

The 3-D finite element model (FEM) configuration represents a novel attempt to honor the known structure of the converging tectonic plates. Modifications of this FEM configuration are used for both forward and inverse models of the M9 Sumatra-Andaman earthquake.

The realistic configuration of the ABAQUS model translates into reliable predictions of seafloor deformation, which, in turn, will generate more accurate models of tsunami behavior. Results of this project will provide insight into the entire earthquake-tsunami system and ultimately improve predictive capabilities for future events.

RESEARCH APPLICATION

Simulating the M9 Sumatra-Andaman Earthquake and Tsunami Source


At the 2006 ABAQUS Regional User Meeting in China, it was announced that six ABAQUS training centers have been founded at regional Chinese universities, including Tsinghua University, Fudan University, Harbin Institute of Technology, Wuhan University, Chongqing University, and Shandong University.

“We are very pleased with the establishment of these regional training centers at leading universities in China,” stated Helen Yu, General Manager, ABAQUS China. “This educational alliance will promote enhanced communication, cooperation, and development of ABAQUS-trained professionals through research expertise, localized technical support, and training.”

From the initial entry of ABAQUS into the Chinese market, the academic world has been important to our growth. In 1997, Professor Zhuang created the Advanced Finite Element Service (AFES) in the department of Engineering Mechanics in Tsinghua University and introduced ABAQUS into the computational mechanics curriculum for undergraduate and postgraduate students. Since its inception, the AFES has trained a significant number of engineers in the use of ABAQUS.

The rapid expansion of ABAQUS in China included adding representative offices in Beijing in 2002 and Shanghai in 2005. The addition of these offices and the increase in our commercial

In March 2007, John Wiley & Sons Ltd. will publish A First Course in Finite Elements by professors Jacob Fish and Ted Belytscho. Developed from the authors’ combined total of 50 years of undergraduate and graduate teaching experience, this book is the ideal practical introductory course for junior and senior undergraduate engineering students. The accompanying advanced

topics at the end of each chapter also make it suitable for graduate level courses, as well as for practitioners who need to extend or refresh their knowledge of finite elements through private study.

A First Course in Finite Elements presents the finite element method formulated as a general-purpose numerical procedure for solving engineering problems governed by partial differential equations. Focusing on the formulation and application of the finite

element method through the integration of finite element theory, code development, and software application, the book is both introductory and self-contained. In addition, the text provides the opportunity for hands-on experience as it contains a link to enable readers to download a complementary copy of ABAQUS Student Edition, allowing them to reproduce many of the book’s examples.

ACADEMIC UPDATE

customers has led to a demand for more engineers trained in using ABAQUS. To facilitate this training, ABAQUS China selected an additional five universities to support growth in the Northeast, North, Central, Southwest, and East regions of China for a total of six ABAQUS Training Centers.

These training centers will carry out training and research that will take advantage of their universities’ respective academic strengths.

A First Course in Finite ElementsBy Jacob Fish and Ted Belytschko

Adopts a generic approach to the subject of FEA and is not application-specific Integrates code development, theory, and application in one book Provides an accompanying web site with access to ABAQUS Student Edition, Matlab data and programs, and instructor resources Contains a comprehensive set of homework problems at the end of each chapter Produces a practical, meaningful course for both lecturers planning a finite element module and students using the text in private study

Bibliographic InformationPaperback * 352pp * March 2007ISBN 10: 0-470-03580-3 ISBN 13: 978-0-470-03580-1 * $65.00 / £34.95 / €52.50

For More Information Visit www.abaqus.com/products/products_academic.html.

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ABAQUS Training Centers Founded at Chinese Universities

New FEA Textbook to be Published

Representatives from China’s leading universities were recognized at the ABAQUS China Regional Users’ Meeting.


Although bearing quality steels are developed to perform under cyclic rolling contact loads, they are also sometimes considered for use in structural machine component applications. In such applications, design engineers must consider unique fatigue-related attributes of rolling bearing steels, mainly the wide range of fatigue results in terms of “cycles to failure” for a group of seemingly identical parts. These steels are highly notch sensitive, thus fatigue durability will also be greatly affected by surface imperfections and sub-surface imperfections such as inclusions.

The process for analyzing fatigue in rolling bearing steels is outlined in a paper by Gabriel Dambaugh of Schaeffler Group USA. His paper documents the use of ABAQUS/Standard for static structural FE analysis of a tripod roller, which is made from high-hardness bearing grade steel (Figure 1). The “simple” roller geometry and fatigue test method provides for an easy analysis setup with ABAQUS by sectioning the model with three planes of symmetry (Figure 2). Mirrored output plots from the completed finite element analysis using ABAQUS/CAE were also created (Figure 3).

Figure 1: INA USA photo of Tripod Rollers assembled in the bearing application prior to CV joint assembly.

Figure 3: FE stress output of tripod roller showing likely fatigue area in red.

Figure 4: Actual tested parts failed from inner fiber crack origination point, just beneath load. Figure shows load point witness mark on OD.

Figure �: Final meshed FEM of tripod roller.

ALLIANCES UPDATE

Cluster computing has been gaining widespread acceptance in the engineering marketplace due to its compelling price-performance value proposition. One of the challenges of qualifying and optimizing HPC software on clusters is the myriad of independent interconnect switches and message passing interfaces (MPIs) that are available. To solve this problem, developers at SIMULIA sought a “universal solution” to maximize the number of platform configurations it could qualify and support for the ABAQUS product line.

With the release of ABAQUS Version 6.6, SIMULIA standardized on Hewlett Packard’s HP-MPI, which is a single software library that supports a broad range of interconnects on Linux, HP-UX, and Windows Computer Cluster platforms. “HP-MPI has proven to be a robust solution that enables us to provide maximum coverage for cluster configurations while mitigating costs and not sacrificing performance,” stated Colin Mercer, VP of SIMULIA Product Development. “It also provides for good error handling, which is critical to customers running commercial software in production environments.”

Critical SIMULIA requirements for an acceptable MPI solution included robustness and high performance across multiple

platforms. In addition, the solution needed to be readily and freely available and backed by reliable technical support. SIMLULIA found all of these solution attributes in Hewlett-Packard’s high-performance HP-MPI.

For More InformationA listing of the cluster configurations for which HP-MPI is qualified and distributed can be found at www.abaqus.com/support/sup_systems_info.html.

Performance information for HP-MPI powered systems can be found at www.abaqus.com/products/performance66.html.

Schaeffler Group Simulates Fatigue of High Strength Rolling Bearing Steels

For More InformationVisit www.schaeffler.com or download the paper “Fatigue Considerations of High Strength Rolling Bearing Steels” by Gabriel F. Dambaugh, Principal Mechanical Engineer, Schaeffler Group USA, Inc. at www.abaqus.com/products/products_fe-safe.html.

Platforms Leveraging HP-MPILinux x86-32: GigELinux x86-64: GigE, Myrinet GM, Myrinet MX, Voltaire IB,

Silverstorm IB, Mellanox IB, Cisco Topspin IBLinux Itanium: GigE, Myrinet GM, Voltaire IB, Quadrics QsNet IB

HPUX Itanium: GigE, Cisco Topspin IB

Gigabit Ethernet ► GigEInfiniband ► IB

ABAQUS results were then imported into fe-safeTM, the fatigue analysis software from Safe Technology, Ltd. The proper loading inputs were straightforward and easy to use with the fe-safe

GUI; default material and surface parameters were also used as a convenient starting point. Finite life fatigue assessment studies correlated very well with laboratory testing of real parts in terms of expected median (L50) lifetime (Figure 4).

HP-MPI: The Standard Message Passing Interface for Cluster Computing with ABAQUS


2006 Regional Users’ Meetings - Everywhere Around the World

EVENTS UPDATE

For More InformationVisit www.abaqus.com/news/regional_meetings.html.

B e n e l u x

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Each year, ABAQUS users around the world gather to

share their experience and knowledge at our Regional Users’ Meetings (RUMs). In 2006 there were

more than twenty-five RUMs that were attended by more than 2,000 customers and alliance partners.

The regional meetings provided ABAQUS users a closer look at the newest functionality in the ABAQUS Version 6.6 Extended Functionality Release. This release accelerates the delivery of newly developed features in a fully tested and

supported product release prior to the next annual release of ABAQUS.

It is clear that customers who take time to share their ABAQUS experience at the RUMs contribute greatly to the success of these meetings. More than 100 customers from a wide range

of industries presented their innovative applications of ABAQUS this year.While there are too many presentations to list them all here,

a sampling of the quality presentations include:

• Global Buckling Analysis of Subsea Pipelines by DNV (Scandinavia)• New Results of Impact and Fracture Studies at MIT (Americas East)

• Paper Feeding Performance of an HP All-In-One Printer (Americas West) • Influence of Local Defects on the Postbuckling Behavior and on the Global Failure of

Stiffened Shell Structures by Airbus Deutschland GmbH (Germany)• Geotechnical Simulation at Petrobas (South America)

• FE Modeling of Roll Design—Cost Savings and Applications to Capital Project Planning at Corus (United Kingdom)

Thank you to all presenters, partners, and attendees for taking the time to be a part of these meetings and for contributing your

valuable feedback. Your participation drives future enhancements of the ABAQUS

product suite.

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Mark your calendars now to participate in the 20th annual international ABAQUS Users’ Conference, May 22–24, at Le Meridien Etoile Hotel in Paris, France. From the first AUC in 1988, to the most recent 2006 conference in Boston, our customers have assembled to share their knowledge and experience in advancing finite element analysis methods and technology. The 2007 conference builds on this tradition by providing an international forum to learn how professionals in engineering, research, and academia are improving product performance and accelerating innovation. Plus, attendees have the unique opportunity to discover the current SIMULIA strategies and ABAQUS product plans.

Valuable Customer PresentationsOur customers’ commitment to presenting their strategies and applications is the main reason for the ongoing success of the AUC. Conference attendees will gain valuable knowledge from industry experts. This year our conference features invited lecturers by:

Jean-François Imbert, Vice President, Head of Structural Analysis Engineering/Center for Competence Structure, ESA AIRBUS France, and Franz Zieher, Head of CAE Engineering and Technology, Powertrain Systems, AVL LIST GmbH.

More than 70 technical abstracts have been received from our worldwide customers. This year’s presentations will be carefully selected to advance the conference’s reputation for outstanding quality. Visit the AUC website to view a complete listing of abstract titles.

Advanced Seminars, Lectures, and TutorialsOn Monday, May 21, 2007, attendees have the option of registering for ABAQUS Advanced Seminars. These training seminars provide in-depth instruction on the theory and application of the latest ABAQUS capabilities. During the conference, general lectures by SIMULIA product management will provide overviews of features in the upcoming ABAQUS releases. The conference concludes with ABAQUS Tutorials that allow users to explore new and advanced capabilities in depth.

Evening Networking EventsYour conference registration includes breakfasts, breaks, lunches, and evening social events that provide you significant time to network with your peers. At our closing banquet you will be able to enjoy breathtaking views of Paris and a fabulous dinner as we cruise along the historic Seine River. Tickets are available for guests, but space is limited, so make your reservation today!

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Image and Animation ContestThe 2nd annual Image and Animation Contest is now open. Take time to enter up to three images or animations. Entries will be judged in two categories: Best Image and Best Animation. Submit an entry today to have your work recognized as best-in-class. A grand prize winner in each category will receive a ThinkPad T43 laptop computer, compliments of IBM Corporation. Entry deadline is March 30, 2007.

Alliance Partner PavilionA unique part of the conference is our Alliance Partner Pavilion. You will have the opportunity to explore complementary solutions that will help you improve productivity and streamline your overall engineering process. Current sponsors include:

ATA Engineering, Inc. Beta CAE Systems SACD-adapco Group Computational Engineering International (CEI)DatapointLabs LLCElysium Inc.e-Xstream engineering SA Fraunhofer Institute SCAIHewlett Packard CompanyIBM CorporationLMS International Microsoft Corporation Safe Technology Ltd. SGI

Conference ProceedingsAn important benefit of your attendance at the AUC is the Conference Proceedings. You will receive a high-quality proceedings book and companion CD-ROM with all of the conference papers submitted by your peers.

For More Information and to Register OnlineVisit www.abaqus.com/AUC2007.

ABAQUS Users’ Conference 200720 Years of Sharing Knowledge and Experience

EVENTS UPDATE

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About ABAQUS, Inc.Founded in 1978, ABAQUS, Inc. is the world’s leading provider of advanced Finite Element Analysis software and services that are used to solve real-world engineering problems. The ABAQUS software suite has an unsurpassed reputation for technology, quality, and reliability and provides a powerful and complete solution for both routine and sophisticated linear and nonlinear engineering problems. ABAQUS delivers a Unified FEA environment that is a compelling alternative to implementations involving multiple products and vendors. In October �005 ABAQUS became a wholly owned subsidiary of Dassault Systèmes, the world leader in 3-D and Product Lifecycle Management (PLM) solutions. ABAQUS, Inc. is headquartered in Providence, RI, USA, with worldwide R&D centers, offices, and distributors for development, technical support, sales, and services.For more information,visit www.abaqus.com.

About SIMULIASIMULIA is the Dassault Systèmes brand that delivers an open platform for multidisciplinary analysis as well as a scalable portfolio of realistic simulation solutions including Abaqus and the CATIA Analysis applications.By building on established technology, respected quality, and superior service, SIMULIA makes realistic simulation an integral business practice that improves product performance, eliminates physical prototypes, and drives innovation. Headquartered in Providence, RI, USA, with R&D centers in Providence and in Sureness, France, the SIMULIA brand provides sales, services, and support through a global network of regional offices and distributors.For more information,visit www.simulia.com.

Copyright © Dassault Systèmes, �007, All rights reserved. The following are trademarks or registered trademarks of ABAQUS, Inc., a wholly owned subsidiary of Dassault Systèmes: ABAQUS, ABAQUS/Standard, ABAQUS/Explicit, ABAQUS/CAE, ABAQUS for CATIAV5, and the ABAQUS logo. The 3DS logo and SIMULIA are trademarks or registered trademarks of Dassault Systèmes. Other company, product, and service names may be trademarks or service marks of their respective owners.

MAR_INS_Y07_VOL9

Documents

INSIGHTS - · PDF fileABAQUS Insights Feb/March 007 INSIGHTS In this issue: ABAQUS Training Schedule and Web Seminars Letter from Scott Berkey, Vice President, Worldwide Operations