Информация за научни конференции и семинари, посветени на математичното
моделиране и компютърната симулация
( март, 2013)
Practical Introduction to FEA
An opportunity to ensure that
your organization gets
maximum benefit from using FEA
3-Day Training Course : Introduction to FEA
FEA has become widely used and universally accepted in many industry sectors. 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.
However for those engineers embarking on FEA, or companies adopting the technique to improve designs or achieve certification of new products, there is a steep learning curve to overcome.
There are a bewildering array of element types, solution types, meshing methods and pre-post processing options that have to be faced. This is before we get down to the engineering physics behind the problem, with associated classic traps and errors. What is needed is guidance via a thorough but practical assessment of the method and how to use it in the real world.
NAFEMS, the only vendor neutral, not-for-profit organization with the aim of promoting the effective and reliable use of FEA, addresses this requirement by providing this three day example-driven, practical course.
Students are shown the background to the FEA methodology, via simple real examples with a minimum of theory. The strength and weaknesses of the various FEA techniques are shown and discussed. Practical considerations of loadings, boundary conditions and structural details are shown by numerous examples.
The assessment, validation and interpretation of FEA results are vital for delivering safe, effective products. A process is shown which provides confidence in the results and aims to provide conservative, reliable and qualified results. The attendees join in the activity of building this process themselves and come away with an embryo Procedural Check List
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.
Interaction is encouraged throughout the course. Real world examples are given at every stage, drawn from the Tutors wide practical experience. Questions are very welcome, as this is one of the key aspects of making this a unique experience for each attendee. Attendee project examples can often be incorporated into the class as time permits, to benefit all. Role playing situations include the class acting as a syndicate to evaluate a Design Failure, critical assessment of an FE Report and the continuous evolution of the Check List.
The course is completely code independent, attendees are welcome to bring laptops to take notes, but they are not required.
A full set of printed and bound
notes will be issued to every attendee.
Practical Modelling of Joints
and Connections
Thursday May 9th, 16th & 30th.
all sessions are recorded, and available to view at any time**
Three-Week Training Course
(one week break on May 23rd)
(one 2.5 hour session per week)
Engineering Board PDH Credits: 7.5 hours*
REGISTER TODAY TO TAKE ADVANTAGE OF THE EARLYBIRD OFFER
Prices will revert to $288 for
NAFEMS Members and $432 for non-members on
Course Overview
Most structures involve some form of jointing or connection. Traditional fabricated structures have used many thousands of bolts and rivets to connect components together in a continuous manner, in the case of ships and aircraft the total can run into millions.
Even today many structures rely on this type of technology – for example the use of spot welds in a modern road vehicle. Significant discrete load paths are formed by lugs and pins, clips or similar connectors in many structures across a wide range of industries.Alternative forms of connection are welds joints and bonded joints. These may well exist as the sole means of load transfer or be supplemented by mechanical connections such as bolts or rivets.
The engineer is faced with an often difficult decision when attempting to simulate such connections and joints within a Finite Element Analysis. In many cases the details of each individual connection can be ignored if an overall stiffness or strength assessment is to be made and the connection is assumed reasonably continuous. However there may be doubts about the local flexibility and load paths developed with this assumption. It may be that the assessment of the local behavior of the connector is essential to the safety case. This would certainly be the case with main attachment fittings for example.In some cases the interaction between the connectors and the surrounding structure is critical, as in the case of pre-loaded bolts and inter-rivet buckling.
Modeling of weld features to get a reasonable estimate of stress concentrations at the weld toe can be problematic; do we model with a fine detailed 3D model, or use a ‘hot spot’ type of approach?
The objective of this course is to review the various connection and joint technologies in use, give an overview of the physics involved and show how to successfully implement practical solutions using Finite Element Analysis.
Course Process and Details
In the current climate travel and training budgets are tight. To help you still meet your training needs the following e-learning course has been developed to complement the live class. The e-learning course runs over a three week period with a single two hour session per week.
The course is completely code independent. No software is required.
Each topic in the class is treated as a building block and is presented using an overview of the physics and theory involved. The math is kept simple and the emphasis is on practical examples from real life to illustrate the topic. The mapping to Finite Element analysis techniques is shown with numerous workshops. The tutor will be showing analysis results interactively and involving the students in the process via Q and A periods during each session, follow up emails and a Course Bulletin Board
Students are welcome to send in problems from industry and these will be discussed as time permits.
Full notes are provided for the students, together with personal passwords for e-learning backup material, bulletin board access etc.
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 .
Course Contents
Bolts and Rivets
Overview
Review of practical designs and applications
Additional bolting calculations
FE Modeling Methods
Bolt and Rivet Groups
Rigid and flexible spider elements used in bolt and rivet loading distribution
Single bolts/rivets
Overall Stiffness and load path assumptions
Influence of clamped structure
Influence of bolt pre-load
Different approaches between rivets and bolts
Line element representation with spider
Shell element representation with spider
Solid element representation with spider (nugget or bolt section)
Inter-rivet buckling and other instabilities
Pre-loading methods
Internal forces directly applied
‘freezing’ of elements to induce pre-strain
Usage with linear and nonlinear contact surfaces
Overview of application and methodology
Types of Linear Contact
Nonlinear Contact Issues
Interference Fit
Detailed modeling of bolts and rivets in linear and nonlinear analysis
Full 3D simulation
Axisymmetric Idealization
Nonlinear Effects
Frictional effects
Fatigue and Fracture Mechanics of bolts and rivets
Lugs
Overview
Review of practical designs and applications
Traditional lug failure modes and calculations
Bearing Distribution assumptions
FE Modeling Methods
2D Shell modeling
3D Solid modeling
Constraint or Loading based methods
Linear and Nonlinear Contact methods
Interference fits
Fatigue and Fracture Mechanics
Welds
Overview
Review of practical designs and applications
Traditional welding classifications and calculations
FE Modeling Methods
Weld simulation with 2D shell models
Weld simulation with 3D solid models
Weld Toe stress concentrations
Hot Spot methods
Bonded Joints
Overview
Review of practical designs and applications
FE Modeling Methods
2D thin shell models
2D plane strain methods
3D solid models
Cohesive Zone Failure Modeling
VCCT Failure Modeling
Practical Introduction to CFD
Three Day Course - 14th to 16th
May 2013
NAFEMS, the only independent not-for-profit organisation
with the aim of promoting the effective and reliable use of CFD, addresses this
requirement by providing this three day example driven, practical course. The course offers excellent guidance on how
to judge which numerical approximations are acceptable and appropriate for
solving a wide range of practical problems.
Of equal importance is the manner in which results are interpreted. Advice is provided which allows the correct
decisions to be taken, based on results which are known to be reliable. Interaction is encouraged throughout the
course, with the planning and design of a complete CFD project and examples of
simple hand calculations, mesh designs and solution designs being set for the
class to complete. The course is
completely code independent.
All aspects of successful CFD application are
covered, including:
The Finite Volume Method
The computational mesh
Turbulence
Sources of error
Interpretation of results
Validation
Attendees should have a graduate engineering
background including some knowledge of fluid dynamics and engineering
mathematics
The material that is presented is independent of
any particular software package, making it ideally suited to current and
potential users of all commercial finite volume method CFD software systems. Anyone who wishes to use CFD in an industrial
context would benefit from this course and it is a must for engineers who wish
to use advanced CFD as an effective predictive tool for industrial flow
analysis.
The course is open to both members and non-members
of NAFEMS.
Topics Covered
Introduction
- Examples of CFD Simulations / Advantages and
Disadvantages of CFD
Basics of Fluid Mechanics
- Basic Equations of Fluid Mechanics (Continuity,
Momentum and Energy Equations)
Introduction to Numerical Methods
- Mathematical Background
- Finite Volume Method
- Spatial Discretization
- Temporal Discretization
- Solution of the Navier-Stokes Equations (Pressure
Correction)
- Grid Generation
- Solution of Systems of Linear Equations
Special flows
- Turbulent Flows
- Multiphase Flows