For many years, finite element modeling has been the job of a specialist; the tools used to perform even simple finite element analysis have been complex enough to require a subject matter expert. This is primarily due to the complex, difficult to understand graphical user interfaces of these products. The job is made further difficult to perform due to the requirement of advanced engineering subject knowledge by the analyst.

Can a mechanical designer who uses CAD tools to create engineering drawings be trained to perform engineering simulations?

In today’s product availability scenario, the answer is “yes.”

A CAD designer using CATIA can create and execute simple finite element models within the CATIA environment by using CATIA workbenches that have been developed for simulations. This makes it intuitive and easier for designers to ensure that their parts meet their design requirements.

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How the simulation methodology gets simplified using designer level tools

  • No need of an expert level analyst tool to perform simple finite element simulation.
  • No need of manual data transfer between design and analysis departments.
  • No need of geometry clean up tools to fix data translation errors.

There are obvious benefits to adopting this simplified approach that integrates the design and analysis environments. The designer can predict design problem early in design process; subsequently the designer can check various alternatives of design in less time. This is primarily due to the tight integration of designer level tools with knowledge based engineering that allows the designer to deliver better product in less time.

Part Level Simulation

From a geometrical perspective, the simulation model can be generated at part level to begin with. The native integration within CATIA allows users to perform stress, displacement, and vibration analysis at any time in the design process, allowing more accurate sizing of parts and fewer design iterations. Individual parts consisting of solid, surface, and wireframe geometries can be analyzed under a variety of loading conditions. The analysis specifications, such as loads and restraints, are associative, with the design allowing users to perform analyses quickly and easily. These specifications are then automatically incorporated into the underlying finite element model, meaning that users do not have to work directly with the finite element model. “Virtual parts” allow items like forces, moments, and restraints to be easily modeled without having to have a detailed geometric representation.

Standard reports can be automatically generated in HTML format, providing clear and detailed information about the results of the analysis, including images associated with the computations. These reports can be used to document the analyses that have been performed and to communicate the results of the analysis to other stakeholders in the organization. CATIA V5 Analysis users benefit naturally from the overall PLM solution provided by Dassault Systèmes, including ENOVIA V5 for data and product lifecycle management. CATIA V5 Analysis users can store, manage, and version all the data associated with their product’s simulation and share the information within the extended enterprise. This unique capability allows collaboration and provides access to advanced PLM practices such as concurrent engineering and change management.

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     Assembly level simulation

 If the concept of virtual parts does not hold good anymore and the complexities of various parts interacting with each other make assembly level simulation mandatory, it is possible to create analysis models for assemblies as well. The analysis of assemblies, including an accurate representation of the way the parts interact and are connected, allows for more realistic and accurate simulation. The designer does not have to make simplifying assumptions about the loading and restraints acting on an individual part. Instead the part can be analyzed within the environment that it operates with the loading automatically determined based on the way the part is connected to and interacts with surrounding parts.

The various types of connections that can be modeled include bolted connections, welded connections, pressure fitting connections, and many more. To make the job further easier for the designer, these connections can be defined using assembly level constraints that already exist in the CAT Product model. Once the design changes, the associated assembly constraints as well as corresponding FEA connections get updated, thereby creating an updated FEA model that is ready for analysis.

         Concurrent engineering made easier 

The “assembly of analysis” capability enables concurrent engineering. For example, the various parts in an assembly can be modeled and meshed separately by different users. They can either use the CATIA V5 meshing tools or import orphan meshes (meshes that don’t have any geometry associated with them) developed outside of CATIA Analysis using a variety of different modeling tools. The user responsible for analyzing the assembly can consolidate the different meshes, connect the parts, apply the loading specifications, and run the simulation. This can significantly reduce the turnaround time when analyzing large assemblies, particularly since some of the parts may have already been analyzed and therefore, the analysis models would already be available.

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Extended solver capabilities

The basic level FEA solver present in the CATIA designer workbench is called the “Elfini” solver and can model only simpler physical problems such as linear materials, small deformations, small rotations and bonded contacts; real life problems can be much more complex and may necessitate the need of an advanced solver. To address such scenarios it is possible to include the well known non-linear solver Abaqus into the CATIA designer environment; it can model the effects of geometric nonlinearity, such as large displacements, and allows nonlinear materials to be included, such as the yielding of metals and nonlinear elastic materials like rubber. It also offers more advanced contact capabilities including the ability to model large relative sliding of surfaces in contact.

The Abaqus capability enables the effect of multiple steps to be analyzed, where the loading, restraints, contact conditions, etc., vary from one step to the next. This powerful technique allows complex loading sequences to be modeled. For example, a pressure vessel might be subjected to an initial bolt tightening step, followed by internal pressurization, and conclude with thermal loading.

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My last post outlined on deriving more value out of PLM data through reports. The complexity of data in the engineering environment is skyrocketing, and Teamcenter as a PLM system provides advanced reporting capabilities for enterprise data, including the data managed in external systems like MRP & ERP.

The Teamcenter Report Builder application provides basic reporting capabilities for data managed inside Teamcenter. It supports two kinds of reports:

  1. Summary Reports
  • Reports that summarize similar information – forreportbuilder example, reports that show all the employees, all the items belonging to a user, or the release status of items
  • Context Independent reports – no object selection required
  • Generated from Teamcenter saved queries
  1. Item Reports
  • Reports that can be run on a particular object – for example, BOM or workflow information for a given object
  • Executed in the context of one or more objects

Behind the scenes, Report Builder uses Teamcenter queries based data dump and supports output to common formats like Excel, XML, Text and HTML.  It’s easy to build these simple reports based on Teamcenter queries, and they can be run from both rich client and Active Workspace client.  Excel can be further leveraged for complex processing, charting, and aggregation of the output.

tcraThe Teamcenter Reporting & Analytics module provides additional advanced reporting capabilities. It can summarize information and present data from many sources in a single report using an easy to build, configurable, drag and drop layout.

It can leverage standard formatting tools like headers/footers, dates, page numbers, report names, filters, tables, charts, and elements. Reports can be run from both Active Workspace or Teamcenter Reporting & Analytics client. It has business intelligence designed for Teamcenter and to understand the relationships and associations of PLM information.tcra1 It comes with over 100 out-of-the-box reports in areas like Change Management, BOM Reports, Substance compliance, Workflow, Administrator Reports, Verification Management, PMM, Schedule Manager, Requirements Manager. It supports powerful and fast BOM reporting, project planning and status reporting and dashboards, process and change reporting.

It has direct access to Teamcenter data through APIs and has connectors to standard enterprise applications. It can also enforce data security based on the Teamcenter access model.  Additional capabilities include:

  • Customized Analytics
    • Organization-specific process status metrics and KPIs
    • Multi-level root-cause analysis
    • Mean time between failure / to failure (MTBF, MTTF) analysis
    • Historical Performance Analysis
  • Reporting Control
    • Save Snapshots of pre-defined reports
    • Group/Role based Access to report data
    • User Controlled Conditional Formatting
  • Resource Management
    • Automated Report Scheduler and Delivery
    • Submit Analysis to queue for load management
    • Caching Techniques to reuse data cubes

Teamcenter Reporting & Analytics benefits include:

  • Analytics, Dashboards and Traditional Reporting – understand your data to improve your products and processes
  • Time to Value – start with pre-configured reports and enable custom reports for your business in a couple of weeks, not months or years
  • Designed for Teamcenter – enable your entire enterprise to easily understand the information they require to make better decisions
  • Self Service Analytics – enable data discovery through self service analytics designed for Teamcenter and optimized to your needs

item-documentationLet’s review the role of the Item Master in managing components and all of the relevant documentation in Autodesk Vault.  There are three main uses for the Item Master in Vault:

  1. Container for all relevant documentation – Items as a concept in Vault are really nothing more than a container for all the relevant documentation related to a component. This could be a PDF file, AutoCAD drawing, or Inventor part and drawing.  This is most commonly done by promoting a document to an Item, where it is assigned an item number.  If an Inventor part or assembly is promoted, the associated drawing is also captured, and this begins the process of capturing all the relevant documentation.
  2. Mechanism for release management – Like individual files, Items also have their own workflows and release process. So rather than trying to manage the release of each individual file, the entire package of relevant documentation can be released from the item level instead.
  3. item-bomCommon BOM format for communication to other business systems – Items also allow the management of a Bill of Materials (BOM). A BOM can be built from scratch from multiple items; however, this is more commonly automated from Autodesk Inventor file relationships.  An Inventor top-level assembly will automatically generate the beginning of a BOM in the Item Master.  This BOM can then be edited to add extra items or change quantities if desired. This BOM can also be exported to a neutral format for communication to other business systems such as ERP or MRP.

So you’re a manager at a manufacturing company. You make things that are useful to your customers and you answer to the executives regarding matters such as budgets, efficiencies, timelines and deliverables. You will have at least heard of PLM; perhaps you have attended a conference or two. But how badly do you need to implement it or retool an existing setup?

Here are 10 indicators:

  1. Your staff is always late meeting deadlines. This results from poorly executed projects, inefficient processes, and lack of clear deliverables. All of these problems can be addressed by a PLM system, starting with the enforcement of common processes and followed up by proper project planning.
  2. Department costs are creeping up. You are held to a tight budget by the organization. You are always close to or exceed your budget and it is difficult to get a handle on why. A PLM system can help this in two ways: more efficient processes leading to greater productivity and by providing better information to managers.
  3. Rework is rampant. A lot of work needs to be repeated or reworked because it was not correct the first time. A PLM system can certainly help with this problem by supporting common working practices and introducing checks at crucial points.
  4. Your department is constantly battling other departments. There is a lot of finger pointing and blame that goes around the organization. No one can pin down who is responsible or when information was provided. PLM can provide automatic notifications, timestamped deliverables, and clear and unequivocal instructions.
  5. There is no accountability in your department. It is difficult to diagnose where mistakes were made and who is responsible. People are always blaming other people. A PLM system can provide objective data that allows the root cause of accountability to be addressed.
  6. Overtime is out of control. Excessive overtime worked in your department is always a concern. A PLM system can help improve productivity and give managers better information regarding where inefficiencies exist.
  7. Your competitors always seem better. Your bosses are always holding you up against your competition and showing how they are better. A PLM system can put you ahead because there’s a good chance the competition do not have a PLM system, or have not made good use of it if they do.
  8. External customers complain that they do not get the information they need. You owe your customers information at various stages during the design cycle and they often don’t receive it in a timely manner. A suitably configured PLM system can improve this dramatically.
  9. Your suppliers provide the wrong information. You are constantly going around in circles with your suppliers regarding information. But do your suppliers have the right capabilities to begin with, and do you have the capability to meet them on the same terms? PLM technology can bridge this gap.
  10. Process adherence is poor. Although you have some level of documented processes, adherence is poor. A correctly configured PLM system can fix this quickly.

Do you have three or more of these issues keeping you up at night? Time to take a serious look at a PLM system.

CATIA has many naming conventions and packaging options. In this post, we’ll be looking specifically at CATIA V5, with future posts examining CATIA V6 and 3DEXPERIENCE.

Version 5 began back in the late 90s as a complete re-write of the previous version. As development progressed, new releases were produced. A release indicates enhanced or new functionality over prior releases – however, still on the same version. A collection of bug fixes would be referred to s Service Pack, and specific bug fixes are referred to as a Hot Fix. Putting it all together we would see something like:

V5 R19 SP 9 HF 108

This would translate to:
Version CATIA 5, release 19, service pack 9, hot fix 108

Why is this important? Because many OEMs require their suppliers to deliver designs that specifically match their own.

Classic vs. PLM Express

When looking for a seat of CATIA, you would be looking for what Dassault calls a configuration. Configurations are commonly referred to by their trigram (a character letter acronym) that is specific to the type of design required. For instance, a mechanical designer would be interested in either an “MD1” or “MD2” – “Mechanical Design 1” or “Mechanical Design 2,” respectively – depending on level of complexity. We call these configurations Classic.

Later, to support their data management solution, SmarTeam, Dassault came up with new bundles called “CATIA PLM Express.” These bundles included licenses for SmarTeam, encouraging use by lowering the cost of entry. This also the first time we see the idea of roles. Rather than bundling functionality by the type of design, in CATIA PLM Express, the bundles are made more intuitive by considering the role of the designer. You could get these bundles, or modules, specific to Manufacturing Engineers, or Layout Engineers. The idea is to gather the modules required by the desired outcome (lathe machined parts, structural steel frames), rather than the methodology (mechanical design). You can build your own PLM Express here.

cat-1074657_1280There are a few additional terms to define when working with PLM Express. It all starts with the bundle called “CATIA TEAM PLM,” or in trigram speak “CAT,” which includes most of the basic design tools and some data management licenses. This is the base configuration upon which everything else is built.

The next level of bundles are called Enablers. Enablers form the starting point of the role-based package. A designer that needs to produce structural steel frames would start their selection in the “Layout Engineer” group of enablers, and would select the one named “CATIA Structure & Steelwork Layout,” or “SSE.” A tooling engineer would look at the group “Mechanical Product Engineer,” and the enabler of choice would be “CATIA Jigs & Tooling Creation,” or “JTE.” In the tooling example, the common way of referring to the package is “CAT+JTE.”

If enablers start the specialization bundles, the next level called Extensions round out. These bundles are very specific to a role or outcome. Case in point is “CATIA Composites Design,” or “CPX.” Another example would be “CATIA Electrical Cable Layout,” or “ECX” found in the “Layout Engineer” grouping, and could be added to the enabler “CATIA Layout & Annotations,” or “LOE.” That would create the final package of “CAT+LOE+ECX.”

A special note: in order to get access to an extension bundle, an enabler bundle must accompany it. In turn, to access an enabler, you must first start with CAT. Think of them as levels of a house: CAT, the base configuration, would be the first floor. The second floor consists of enablers, and the third floor are enablers. You can’t get to the third floor without the second. You can have any combination of enablers and extensions, regardless of the role grouping. So our tooling designer (CAT+JTE), may, for some reason, need access to the Electrical Cable Layout extension (ECX), found in the “Layout Engineer” grouping.

One final note, and this is a biggie.

When an OEM specifies a version level, say V5 R22 SP5 HF 16, they may also prescribe a classic configuration like MD2. This is not gospel. You may use a PLM Express bundle instead; both use the same file formats. They are both V5, and are interchangeable.

This can be extremely confusing, especially for new people just entering the CATIA world, and all these trigrams and bundles can be daunting. Our team can help you determine what you need and put together the bundle that makes the most sense for your situation. Just let us know how we can be of service.

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Composites always had a well-defined place in the aerospace industry because of their properties: lightweight to make overall design lighter and toughness to make overall design bear the aero structural loads. At present, from aircraft fairing to train noses, boat hulls and wind turbines, composites offer dramatic opportunities to meet increasing cost-driven market requirements and environmental concerns. However, modeling of composites in a seamless collaborative environment has always been a challenge. This is because of multiple aspects of composites modeling such as design, simulation, and manufacturing that made it quite a tough task on a single platform.

CATIA composites workbench now offers a solution to address various aspects of composites modeling in a unified manner. The objective of this blog post is to provide information on composites workbench capabilities with respect to design, simulation, and manufacturability of composites.

DESIGN IN ANALYSIS CONTEXT

There are different ways to start the preliminary design of a composite part, but the zone-based design is ideal to capture analysis constraints and predict the behavior of the part inside the design environment by importing thickness laws. The thickness laws are calculated as a result of FEA analysis. The composites part design workbench in CATIA provides easy-to-use dedicated zone creation and modification features. Zone-based modeling contributes to significant time savings with the ability to perform concurrent engineering with mating parts. The image below shows a wing panel with a grid created from ribs and spars in assembly context and thickness law for each cell mapped on the grid from a spreadsheet.

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Once the grid information is ready, Composites workbench provides highly productive automatic ply generation from zone capabilities with automatic management of the ply staggering and stacking rules. The ability to quickly and automatically transition from zones to plies while keeping full associativity, allows the designer to focus on the design intent and helps dramatically reduce the number of geometrical tasks required to design the part.

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To further check the viability of a design from the structural strength perspective, it is possible to perform the FEA simulation within the CATIA environment using the Elifini solver of CATIA analysis. The full associativity with composites workbench is maintained and true fiber angles are taken into account. To address the non-linear aspect of FEA, is it possible to export the plies data in the form of layup files to Abaqus CAE using the composites fiber modeler plug-in. In case design modifications are needed, it is possible to edit and modify any ply or sequence in the composites workbench and instantly export the modified layup file to simulation workbench or Abaqus CAE for validation. Thus designers and analysts can work together in collaboration during the composites development process, saving time, improving product quality, and preventing costly error. […]

Autodesk Vault offers a basic environment for change management that is more flexible and useful for more situations than people realize. The change management interface in Vault appears at first glance to only include a single rigid workflow for change, but upon further investigation you will find that it can be used more broadly.  Let’s take a look:

  1. ECR, ECO, ECN – The Vault change management environment is called “Change Order List,” but that is really misleading.  Different templates can be created for many purposes and these could include Change Request (ECR), Change Order (ECO), and Change Notice (ECN) to name just a few examples.  If using more that one type in your environment, it is common to use prefixes of ECR, ECO, etc. for each template type.
  2. Release management – The change environment can be used as a formal release mechanism as well.  This might be helpful if you want multiple people to review and approve work before it is initially released.  This gives you a location to capture everyone’s comments and thoughts related to the initial release.  A template with a REL prefix is often used for this.
  3. Simple changes – The flowchart for the change environment makes it look like it must be relatively complex, but there are options to shortcut many of the steps for those with the appropriate authority.  The “submit and force approval” and “fast track approval” make it much quicker to transact and capture simple changes.
  4. Complex changes – More complex changes will often use all the steps in the default workflow, and may even go through multiple iterative loops.  This can be done by simply rejecting the approval and re-opening the change.
  5. Simple or complex with the same basic workflow – There is only one formal workflow with the various options built in.  This can be used in many scenarios, and often with different people involved (based on the change template used).  Each change template can have a different routing.  The routing determines which people are responsible for each step in the workflow.
  6. Role of the change administrator – The change administrator is responsible for determining what happens when changes are in the “Open” state. This means someone else could create a change, but the change admin acts as the gatekeeper and determines if the change is really going to be made by submitting it to have work actually done. This means change requests, change orders, approvals, and notification can really all happen as part of the same workflow if you want to keep things simple.

change-order-status

Previously, my colleague Mark Van DeBogert touched in an earlier blog post on the business side of CATIA 3D Master. Today, we are going to go a little further into understanding what is available to purchase from the Dassault CATIA V5 product line. As with a lot of Dassault CATIA products, there are two levels of the Functional Tolerancing & Annotation offering.  The licenses are FT1 and FTA respectively.

The FT1 license allows you to easily create your 3D annotations, tolerances, and specifications, as it does provide a pretty comprehensive set of dress up features, text and flag note features. 3D Dimensioning can be done in both part and assembly levels.  You display and manage your annotations by simply setting up various annotation planes, and you can easily switch a mirrored annotation with the click of a button, as shown below.

The number one and most significant difference between FT1 and FTA is the Tolerancing Advisor.  The advisor guides the user through the creation of annotations and dimensions according to the selected geometrical element, plus an existing annotation and the selected standard (ANSI, ASME, ISO, etc.) the user is working to. For the novice user, it will usually prevent making gross mistakes; it’s pretty much the all-purpose tool for creating annotations, dimensions, and tolerances – it can’t necessarily do everything, but it certainly goes a long way. Everything created using the tolerance advisor is what’s referred to as Semantic.

In order for something to be Semantic it needs to meet two criteria: […]

256px-caught_between_a_rock_and_a_hard_placeThere they were, sailing along their merry way. Toward the horizon, a narrow strait approaches. As the boat gets closer, they notice a couple of strange characteristics; to one side a cliff and the other a whirlpool. Upon arrival, it becomes apparent that this is the cliff where the monster Scylla dwells. Looking to the other side, the monster Charybdis, spewing out huge amounts of water, causing deadly whirlpools. Each monster is close enough that to avoid one means meeting the other. Determined to get through, our intrepid hero Ulysses must make a decision.  The idiom “Between Scylla and Charybdis” comes from this story.  In more modern terms, we would translate this to “the lesser of two evils.”

PLM administrators, engineering managers, and IT teams are often give this same choice with equally deadly – well, unfortunate – outcomes. What is this dilemma? Customize the PLM system (beyond mere configuration) to match company policies and processes, or change the culture to bend to the limitations posed by “out of the box” configurations.

Companies will often say something to the effect of “We need the system to do X.” To which many vendors meekly reply “Well, it can’t exactly do X, but it’s close.” So what is a decisionmaker to do? Trust that their organization can adapt? Risking lost productivity and possibly mutiny? Or respond by asking “What will it take to get it to do X?” incurring the risk of additional cost and implementation time.
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We can further elaborate on the risks of each.  When initially developing the customizations, there is the risk of what I call “vision mismatch.”  To the best ability, X is described with a full understanding of the bigger picture that is missed when the developer writes up the specification.  This leads to multiple revisions of the code and frustrations on both sides of the table.  Then, customizations have the longer-term risk of “locking” into a specific version.  While gaining the benefits of keeping your processes perfectly intact, the system is stuck in time unless the customizations are upgraded in parallel.  Some companies will avoid that by never upgrading…until their hardware, operating systems, or underlying software systems become unsupported and obsolete. Then the whole thing can come to a crashing halt.  Hope the backups work!

office-1209640_1280However, not customizing has its own risks. What if the new PLM system is replacing an older “homegrown” system that automated some processes that the new system cannot? (And a “homegrown” system comes with its own set of risks; original coder leaves the company, never commented code, no specifications, etc.)  For example, raising an issue automatically created an engineering change request while starting a CAPA process. The company has gained a manual process, thus exposing them to human error. Or, perhaps the company has policy that requires change orders go through a “four-eyes” approval process, to which the new system has no mechanism to support such a use case.

Customizing is akin to Charybdis, whom Ulysses avoided, deciding that it is better to knowingly lose a few crew members rather than risk losing the entire ship to the whirlpools. Not customizing  is more like Scylla, where there is lower risk, though a much higher probability to the point of almost certainty.

We’ve been through these straits and lived.  We’ve gone through with many companies, from large multi-nationals to the proverbial “ma and pa” shops.  Let us help you navigate the dangers with our PLM Analytics benchmark.

The Dassault Systèmes SIMULIA portfolio releases new versions of its software products every year, and this year is no different. The first release of Abaqus 2017 is now available for download at the media download portal. SIMULIA has developed and broadcast 2017 release webinars to make users aware of new features available in the 2017 release, but those webinars are long recordings ranging from one to two hours each, which can be daunting. This blog post will provide a brief highlight of materials and explicit updates in Abaqus solver 2017. A more detailed explanation of any mentioned update, or answers to further questions, can be obtained either by listening to the webinar recordings at the SIMULIA 3DExperience user community portal, leaving a comment on this post, or contacting us.

SPH boundary conditions improvements

SPH particles located on opposite sides of a surface cannot interact with each other in the absence of boundary condition. This was not the case in previous releases; in Abaqus 2017, this is the default boundary condition setting. There are further improvements in tensile instability control to prevent instability among particles subjected to local tensile stresses. Below is an example in which there are SPH particles in two different chambers; the lower chamber particles are subjected to displacement BC while upper chamber particles are not subjected to any BC.

DEM improvements

  1. The series and parallel search algorithms for contact are unified to improve the DEM performance. The search cells are created only once.
  2. It is now possible to run DEM jobs with particle generators in parallel mode. This means more than one particle generator can be active while a DEM job is running.
  3. In previous releases, only fixed time increment scheme was available and it was difficult for the user to predict the appropriate time increment. In the 2017 release, an automatic time increment scheme has been introduced.
  4. Adhesive particle mixing is now supported. The algorithm used is called JKR adhesive inter particle contact. Both Hertz contact and friction are supported.

Material Enhancements

  1. There is some good news for users in the health care industry who design and manufacture cardiovascular stents: Super-elasticity, which was previously a part of user subroutines, is now available in the Abaqus 2017 material library. The motivation is Nitinol, a nickel titanium alloy used in cardiovascular stents because of super elasticity, shape memory effect, biocompatibility, and fatigue. The Nitinol model exhibits linear elastic Austensite behavior at lower stresses. On further loading, transformation from Austensite to Martensite occurs but behavior is still linear elastic. Beyond full transformation, Martensite exhibits elastic plastic behavior. A similar phenomenon is observed in compression loading. It is supported in Abaqus CAE.

 

 

 

 

 

 

 

 

 

 

2. A multilinear kinematic hardening model is now available in Abaqus 2017. In previous releases, this model was available as a user subroutine material called ABQ_MULTILIN_KINHARD.  Plasticity follows an array of perfectly plastic subvolumes that follow Von-Mises criteria, each with a unique yield strength. This model offers more flexibility than the linear kinematic hardening model. It is available only in Abaqus standard and intended for thermo-mechanical fatigue of metals. It is supported in Abaqus CAE.

3. The definition of damage initiation and damage evolution of cohesive elements with traction separation response has been enhanced to include rate dependent cohesive behavior. It is available only in Abaqus explicit. Non-linear damage initiation of ductile metals is now supported in Abaqus 2017. This model provides more flexibility to predict damage under arbitrary loading paths. It is available both in Abaqus standard as well as in explicit for ductile, shear and Johnson Cook material models.

 

4. Non-linear damage initiation of ductile metals is now supported in Abaqus 2017. This model provides more flexibility to predict damage under arbitrary loading paths. It is available both in Abaqus standard and explicit for ductile, shear and Johnson Cook material models.

5. The parallel rheological framework model now supports plane stress elements as well, in both standard as well as in explicit.

6. A new subroutine for user defined thermal expansion coefficients has been introduced. It is called VUEXPAN. This routine can be used in explicit to define thermal strain increments as a function of temperature, time, element number, state, or field variable. It is available only with Mises plasticity, Hill Plasticity and Johnson Cook model.

Usability Enhancements

1.Enhancements in distortion control: In Abaqus explicit, it is possible to convert highly compressed solid elements to linear kinematic formulation. Once that happens, the analysis does not stop even if the elements get inverted. It is activated by default when solid elements are used with crushable foam material.

2. Larger stable time increments in Abaqus explicit: In Abaqus 2017, there is an improved estimate method of element characteristic length to get larger stable time increments. It is defined in explicit step as follows:

*Dynamic, Explicit, improved DT method=YES (by default) or NO

It is further possible to invoke this method selectively in individual sets instead of global model as follows

*section control, improved DT method = YES or NO

 

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