PDH Credits - 15*
Attend the live sessions, or view the recordings at your convenience
- What are the most important nonlinear FEA analysis topics?
- What practical hints and tips do I need to be able to carry out nonlinear analysis effectively?
- What theoretical background do I need to understand the implications of my nonlinear analysis?
Get the answers to these questions and more with this industry-leading, code-independent e-learning course.
This 6-session, live, online course addresses the important features of non-linear FEA. The course is independent of any specific software – you won’t get bogged down in the details of specific menus and workflows! You will be able to focus on key background and practical hints and tips, covering topics including:
- Background to non-linear FEA
- Nonlinear analysis strategy
- Geometric nonlinearity
- Material nonlinearity
- Contact nonlinearity
- Explicit analysis background
NAFEMS e-learning gives you the best of both worlds, giving you real, practical knowledge that you can use day-to-day to improve your analyses.
What will you learn?
- The importance of building a sound nonlinear FEA planning, analysis and review process
- The background to the various types of nonlinear analysis
- An understanding of when and how to use nonlinearity
- An understanding of the risks and strategy needed to successfully tackle nonlinear analysis
- Limitations of non-linear FEA simulation
Who should attend?Designers and engineers who are moving into the area of Non-Linear FEA, or need a refresher to brush-up their knowledge. Familiarity with FEA is assumed, but no other background knowledge is required.
Many problems facing designers and engineers are nonlinear in nature. The response of a structure cannot be simply assessed using linear assumptions. Nonlinear behavior can take many forms and can be bewildering to the newcomer.
All physical systems in the real world are inherently nonlinear in nature. One of the most difficult tasks facing an engineer is to decide whether a nonlinear analysis is really needed and, if so, what degree of nonlinearity should be applied. Looking at a bolt heavily loaded in an attachment fitting, it may be that the change in stiffness and load distribution path are critical in evaluating peak stress levels. Perhaps the assembly is in an overload condition and we need to check that plastic growth is stable and there is no ultimate failure – bent but not broken! A flange on a connector arm may be under compressive load, but also sees heavy bending. We need to assess the resistance to buckling with deflection dependent loading paths and possible plastic behavior.
Whatever the nature of the challenge, this objective of this course is to break down the nonlinear problem into clearly defined steps, give an overview of the physics involved and show how to successfully implement practical solutions using Finite Element Analysis.
The course is completely code independent.
- A full set of notes in PDF format will be available for download. Each session is presented live and is available for review via a streamable recording.
- Personal passwords are provided to allow you to access e-learning backup material via our special bulletin board. Reading lists, homework submissions, supplementary data are all stored as files on the bulletin board.
- Interaction via the bulletin board is strongly encouraged to obtain the most from the e-learning class. Typically the board runs for 4 weeks after the last live class sessions, giving you plenty of time to catch up with homework, review and ask questions.
Note: homework is purely voluntary!
Course Process and Details
Students will join the audio portion of the meetings by utilizing the VoIP (i.e. headset connected to the computer via headphone and microphone jacks) or by calling into a standard toll line. If you are interested in additional pricing to call-in using a toll-free line, please send an email to: e-learning @ nafems.org .
This is a six-session online training course, with each session lasting for approximately 2.5/3 hours, depending on homework submissions, questions & discussions.
You can attend the sessions live, and/or by listening to the recordings, which will be made available shortly after the end of each session.
Session 1: Overview of non-linear analysis
- Background to Non-linear
- Linear versus Non-linear
- Types of non-linearity
- Geometric non-linearity
- Example - oil tank
- Material Non-linearity
- Contact non-linearity
- Session 1 homework
Session 2: Geometric non-linear analysis in depth
- Review: Homework Session 1
- Large Displacement or Geometric Nonlinearity
- Shallow roof example
- Non-linear convergence strategy
- Non-linear loading strategy
- Real world boundary conditions
- Scope of the Analysis
- Session 2 Homework
Session 3: Buckling analysis in depth
- Review: Session 2 Homework
- Further Buckling
- Linear Buckling Rod Example
- Further Nonlinear Buckling
Session 4: Contact analysis in depth
- Contact surface methods
- Gap and slideline elements
- Background to contact technology
- Penalty and Lagrange methods
- Modern Contacts
- Contact types
- Setting up contacts
- Contact hints and tips
Session 5: Nonlinear Material analysis in depth
- Yield and Hardening
- Examples using Material nonlinearity
- Viscoelastic material analysis
- Hyperelastic material analysis
- Examples using Viscoelasticity and Hyperelasticity
Session 6: Advanced methods
- Mesh Adaptivity and Element erosion
- Nonlinear Transient Analysis
- Implicit versus explicit FE Analysis methods
- Explicit Background
- Explicit Examples
- Overview of Explicit Analysis
- Lagrangian and Eulerian Elements
PSE Competencies addressed by this training course
|NGECkn1||Identify the contact facilities available in a finite element system, including friction models.|
|NGECkn2||Identify the algorithm used to follow highly nonlinear equilibrium paths in a finite element system.|
|NGECkn3||List common categories of geometric non-linearity and contact.|
|NGECkn4||Identify the extent to which your application software allows modification of geometric nonlinear solution parameters.|
|NGECco1||Discuss the terms Geometric Strengthening and Geometric Weakening.|
|NGECco2||Explain why load sequencing can give rise to different end results and identify relevant examples.|
|NGECco3||Explain how large displacement effects can be handled as a series of linear analyses.|
|NGECco4||Outline how large displacements, plasticity and instability can interact in a collapse scenario.|
|NGECo5||Discuss the term Load Following.|
|NGECo7||Contrast the terms Large Displacement and Large Strains.|
|NGECo8||Discuss the meshing requirements for accurate contact area and contact pressure.|
|NGECo9||Discuss the limitations of contact algorithms available in a finite element system.|
|NGECo10||Discuss the theoretical basis of the contact algorithms available in a finite element system.|
|NGEColl||Explain the challenges of following a highly non-linear equilibrium path with both load control and displacement control.|
|NGECo12||Contrast the Newton-Raphson method and the Riks arc-length method.|
|NGECap1||Identify whether a system has automatic re-meshing and implement a re-meshing strategy as appropriate, due to significant distortion of a mesh.|
|NGECap3||Carry out large strain analyses.|
|NGECap4||Use an analysis system to carry out contact analyses.|
|NGECap5||Conduct analyses with pre-stress and pre-strain.|
|NGECap6||Carry out analyses with load following.|
|NGECan1||Analyse the results from geometrically nonlinear analyses (including contact) and determine whether they satisfy inherent assumptions.|
|NGECan2||Compare the results from geometrically nonlinear analyses (including contact) with allowable values and comment on findings.|
|NGECsy2||Plan modelling strategies for geometrically nonlinear problems, including contact.|
|NGECev1||Assess whether Load Following is likely to be required in any analysis.|
|NGECev2||Select appropriate solution schemes for geometrically non-linear problems|
|NGECev3||Assess whether element distortion effects are affecting the quality of solution and take appropriate remedial action where necessary.|
|PLASkn1||For a beam under pure bending sketch the developing stress distribution from first yield, to collapse.|
|PLASkn7||Sketch a stress-strain curve for an elastic-perfectly plastic and bi-linear hardening material showing elastic and plastic modulii.|
|PLASco1||Discuss salient features of the inelastic response of metals.|
|PLASco2||Explain the terms Isotropic Hardening, Kinematic Hardening and Rate Independency.|
|PLASco4||Explain the terms Limit Load and Plastic Collapse Load and explain why the latter is often a misnomer.|
|PLASco10||Discuss the effects of stress singularities at reentrant corners on limit load.|
|PLASco14||Illustrate typical examples of Local Plastic Deformation and Gross Plastic Deformation.|
|PLASco19||Derive the load-displacement relationship for simple two or three-bar structures with elastic-perfectly plastic materials. Repeat the derivation for elastic strain hardening materials.|
|PLASco23||Describe the Bauschinger Effect.|
|PLASco25||Explain why finite element solutions tend to become unstable as the limit load is approached.|
|PLASco26||Discuss approaches employed to improve the finite element prediction of limit load.|
|PLASco27||Explain the process of Stress Redistribution.|
|PLASco31||Discuss the general relationship between finite element mesh and size of plastic zone.|
|PLASco37||Describe why the incompressible nature of plastic deformation can cause difficulties with analysis.|
|PLASap7||Using standard material data, derive a true stress vs true strain curve to be used for nonlinear analysis.|
|PLASan2||Compare the results from nonlinear material analyses of typical pressure components with allowable values and comment on findings.|
|PLASsy1||Specify the use of elastic perfectly plastic and bilinear or multi-linear hardening constitutive data as appropriate.|
|PLASsy3||Plan modelling strategies for nonlinear material problems.|
|PLASev3||Assess the significance of neglecting any feature or detail in any nonlinear material idealisation.|
|PLASev4||Assess the significance of simplifying geometry, material models, mass, loads or boundary|
|BINkn1||Define the term Slenderness Ratio.|
|BINkn2||Define the term Radius of Gyration.|
|BINkn3||Define the Determinant of a matrix.|
|BINco1||Explain the terms Stable Equilibrium, Neutral Equilibrium and Unstable Equilibrium.|
|BINco2||Discuss the term Load Proportionality Factor and explain what a negative value indicates.|
|BINco3||Explain why theoretical Buckling Loads (including those calculated using FEA) often vary significantly from test values.|
|BINco4||Explain the term Local Buckling and indicate how this can normally be prevented.|
|BINco5||Discuss the snap-through buckling of a shallow spherical shell subjected to a lateral load and explain why a linear buckling analysis is not appropriate.|
|BINco6||Discuss the term Post-Buckling Strength and illustrate this with examples.|
|BINco8||Explain why symmetry should be used with caution in buckling analyses.|
|BINco10||Explain the effects of an offset shell mid-surface on buckling.|
|BINco12||Explain what a structural mechanism is.|
|BINco13||Explain the meaning of Stable Buckling and provide examples.|
|BINco14||Explain the meaning of Unstable Buckling and provide examples.|
|BINco16||Describe the theoretical steps in a linear buckling analysis, highlighting the role of the Geometric Stiffness Matrix.|
|BINco17||Outline various methods of extracting eigenvalues, including the Power Method.|
|BINco18||Explain when geometric non-linear analysis should be used in a buckling analyses.|
|BINco19||Explain the phenomenon of mode jumping.|
|BINco20||Discuss the terms lateral buckling and flexural-torsional buckling, and provide examples of where this behaviour might arise.|
|Binco23||Discuss the characteristics of thin-walled structures that could influence buckling behaviour.|
|BINap1||Use tables to evaluate Euler buckling loads for common configurations of columns, plates and shells.|
|BINap2||Conduct eigenvalue buckling analyses.|
|BINap3||Conduct post-buckling analyses.|
|BINan1||Compare FEA results with buckling and instability tests and justify conclusions.|
|BINan2||Analyse the results from buckling and instability analyses of typical pressure components and determine whether they satisfy code requirements.|
|BINsy1||Plan modelling strategies for buckling of stiffened plate/shell structures.|
|BINsy2||Plan modelling strategies for plate/shell structures with an offset in midsurface.|
|BINsy3||Plan a series of simple benchmarks in support of a more complex instability analysis.|
|BINsy4||Plan modelling strategies for buckling and instability problems.|
|BINsy5||Prepare an analysis specification for buckling and instability analyses, including modelling strategy, highlighting any assumptions relating to geometry, loads, boundary conditions and material properties.|
|BINev1||Assess the possibility of local and global buckling from the results of a non-buckling analysis.|
|BINev2||Select appropriate idealisation(s) for a buckling analysis.|
|BINev3||Assess whether a non-linear buckling analysis is necessary.|
|BINev4||Select appropriate solution schemes for buckling problems.|
|BINev5||Assess the significance of neglecting any feature or detail in any buckling idealisation.|
|CTDkn6||State the basic definitions of stress relaxation and creep.|
|CTDco1||Describe and illustrate a standard creep curve for steels, highlighting the steady state regime.|
|CTDco2||Using the standard creep curve, describe the effects of (i) increasing stress level and (ii) removing the stress.|
|CTDco3||Describe different ways of presenting creep data.|
|CTDco7||Explain, in general terms, the creep solution process as typically implemented in finite element systems.|
|MASco7||Describe the following constitutive behaviour for materials relevant to your industry sector: hyperelastic, viscoelastic, viscoplastic.|
|MASco18||Describe the effects of strain rate (if any) on the behaviour of materials used in products within your organisation.|
Not Available to Attend this Time?
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*It is your individual responsibility to check whether these e-learning courses satisfy the criteria set-out by your state engineering board. NAFEMS does not guarantee that your individual board will accept these courses for PDH credit, but we believe that the courses comply with regulations in most US states (except Florida, North Carolina, Louisiana, and New York, where providors are required to be pre-approved).
Telephony surcharges may apply for attendees who are located outside of North America, South America and Europe. These surcharges are related to individuals who join the audio portion of the web-meeting by calling in to the provided toll/toll-free teleconferencing lines. We have made a VoIP option available so anyone attending the class can join using a headset (headphones) connected to the computer. There is no associated surcharge to utilize the VoIP option, and is actually encouraged to ensure NAFEMS is able to keep the e-Learning course fees as low as possible. Please send an email to the e-Learning coordinator (e-learning @ nafems.org ) to determine if these surcharges may apply to your specific case.
Just as with a live face-to-face training course, each registration only covers one person. If you plan to register a large group (10+), please send an email to e-learning @ nafems.org in advance for group discounts.
For NAFEMS cancellation and transfer policy, click here.