Practical Introduction to Finite Element Analysis (FEA)
FEA is a powerful technique, able to produce solutions to challenging structural analysis problems. The technology and computational efficiency of the method, together with the rapid increases in computer processing power means that today the scope and size of simulations far exceeds the capabilities of even a few years ago.
Description
The course offers excellent guidance on how to assess and plan the task of carrying out a structural analysis using FEA. A clear understanding of the objectives of each analysis is vital and a road map for achieving this is presented. A review of the tradeoff between available resource and analysis methodology is given.
Course Program
Background to FEA
- Origins of FEA, leading to today’s process
- Emphasis on limitations of a displacement solution
- The route from CAD to Mesh to Solver to Results
- A simple case study – a plate with a hole
- The Analysis Input file
- Simple Element stiffness matrices
- Grid Points , Degrees Of Freedom (DOFs)
Overview of Element Types
- 1d elements
- 2d elements
- 3d elements
- Solid 3D elements: Hex versus Tets, the trade off
- Types of meshing and meshing issues
- I-beam example spanning element types
Making healthy models
- Mis-matched DOF’S and other issues
- Element distortions – effect on accuracy
- Convergence checking
- Solver and Preprocessor checking
- Post processor checking and the dangers of smoothing
- Stress concentrations and stress singularities
- Window cutout example
- Building an Analysis Process ‘Cheat Sheet’ Part 1
Constraints
- Constraint methods
- Real world boundary conditions
- Poisons effect
- Minimum support 321 method
- Case Study – bracket analysis
- Linear Contact methods – new technology to supplement constraints
Loading Types
- Distributed load, Point Loading
- Real world loading versus FEA
- Bearing load methods
- Nonlinear implications
- Centrifugal and Inertial Loading
- Unit load cases for better understanding
- Case Study – tanker body under cornering and accident loading
Multi Point Constraints (MPCs)
- What are they and why use them?
- Different terminologies and usage
- Soft and rigid load and constraint distribution
Making Life simpler
- Symmetry
- Anti-symmetry and Axi-symmetry
- Sector Symmetry
- Plane Stress
- Plane strain
- Comparing 1d, 2d, 3d modeling case study of a pressure vessel
Understanding the objective of the analysis
- Clear view of scope of problem – how do we tackle it
- Resource and timescale factors
- FEA Analysis objectives – reservoir case study
- Class exercise develop an analysis strategy
Looking at CAD geometry
- Why not use 20 million elements
- Trade offs
- De-featuring
- The reality of CAD models
- Manual methods of meshing
- Building an Analysis Process ‘Cheat Sheet’ Part 2
Engineering Assessment
- Anticipate the load paths
- Free body Diagrams
- Force Balance
- Review of Stress and Load fundamentals
- Revisiting the I-Beam, comparing theory with FEA
Checking the answers
- Ways of checking the results
- What type of stress do I use?
- Review of fundamentals
- Post Processing and More Checking
- Other Checks
- Class Exercise – review an FE report
Other Topics
- Buckling
- Introduction to Non-linear Analysis
- Introduction to Dynamics and Normal Modes Analysis
- Introduction to Composite Analysis
Conclusions
- Review of the Class exercise – developed Analysis Process ‘Cheat Sheet’
- Debrief