Learning The FE Method - Any Advice?
Learning The FE Method - Any Advice?
(OP)
I plan to attend the NAFEMS Practical FE course in March. Does anyone know if its any good?
I'm a beginner with some experience but I really want to understand the basics of FE and not just how to use a piece of software (ie Femap Patran etc). I have a few books which have helped get me started, but I was wondering if anyone has any tips on how they got started. Id like to learn as much as I can on my own before going on the course, just so that I dont get overwhelmed...
Also, ideally I'd like some simple FE software to allow set up some basic models and try and understand the results, something I can compare against traditional hand calcs. Does anyone have any suggestions? By free I mean freeware or something, I don't do cracked commercial software.
I'm a beginner with some experience but I really want to understand the basics of FE and not just how to use a piece of software (ie Femap Patran etc). I have a few books which have helped get me started, but I was wondering if anyone has any tips on how they got started. Id like to learn as much as I can on my own before going on the course, just so that I dont get overwhelmed...
Also, ideally I'd like some simple FE software to allow set up some basic models and try and understand the results, something I can compare against traditional hand calcs. Does anyone have any suggestions? By free I mean freeware or something, I don't do cracked commercial software.





RE: Learning The FE Method - Any Advice?
before you start with simple models (i'd start with beams, then shells) model things you can solve be hand (including redundant problems) ...
i'd recommend running single element "patch" tests. simple restraints, single loads, how does the elemnt compare with classical analysis. this teaches you the weaknesses (and strengths) of different elements, when to use them, how to use them, to get good results, when to be carefull of what the "lying little buggers" are telling you !
there are plenty of free software out there for doing what you want, NASTRAN has a demo version. whilst most codes use very similar elements, the devil (as always) is in the details, and each code will have it's own subtle differences (in NASTRAN, don't ever use AUTOSPC !)
get some real help too, at least a text book, maybe a post-grad course too; i'm not really a fan of seminar courses but if you go prepared then you won't be blown out of the water on the fist day.
good luck
RE: Learning The FE Method - Any Advice?
A single element test will certainly highlight its limitations, but the strength of the method is that with more elements the results improve and as you further increase mesh density you should see your results converging on the analytical result (for simple problems with an analytical result of course - like a hole in a plate). This process is commonly referred to as "mesh convergence".
A great freeware FE software is CalculiX, there are both windows and linux versions available.
www.Roshaz.com
RE: Learning The FE Method - Any Advice?
And it doesn't hurt that the input files are almost exactly the same as Abaqus.
RE: Learning The FE Method - Any Advice?
As mentioned by rb1957 NASTRAN has a demo version
Abaqus has a $99 student edition: http://www.simulia.com/academics/purchase.html
In the end it is absolutely great that you are building a strong foundation. Make sure that your resume shows this rigor. Also, show some advanced skills that places need. I specifically look for complex contact, hyperelastic materials, and strains in excess of 100%.
Rob Stupplebeen
RE: Learning The FE Method - Any Advice?
- Just a slightly steep learning curve there Dan!
www.Roshaz.com
RE: Learning The FE Method - Any Advice?
johnhors- If you don't mind looking through code and take baby steps it's really a good way to get a handle on not only the analysis part but also the limitations. But it can be a decent amount of work and take a little while.
RE: Learning The FE Method - Any Advice?
Bear in mind I am just trying to get as much backround learning now before going on the course, after which hopefully I will have a better understanding. Then perhaps after that I can go into more depth and look into how this method is used in industry.
RE: Learning The FE Method - Any Advice?
Cheers
Greg Locock
SIG:Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Learning The FE Method - Any Advice?
NASTRAN is better to study if you want a job because more people use NASTRAN but it is a bit of a dog to use, the input deck formats are user-hostile and there are quite a few wierd tricks like AUTOSPC, KROT6 etc ready to trip up the beginner.
A good place to start is modelling a cantilever beam in a) beam elements, b) shell elements and c) solid elements. You have simple equations for the hand calcs to compare with and will learn a lot about the different elements. Then try a plate with a hole and do some stress concentration factors for linear stress. Then add a nonlinear material and see what really happens at a hole when the stress concentration exceeds yield and you get plasticity.
good luck
gwolf.
RE: Learning The FE Method - Any Advice?
There's quite a few good lectures to watch on youtube.
Here's the intro lectures
The first Video is by the Department of Mechanical Engineering, IIT Madras.
http://www.youtube.com/watch?v=djd9-f-onLs
Second video is by the Department of Aero Space IIT Kanpur.
http://www.youtube.com/watch?v=NYiZQszx9cQ
I think there are about 40+ lectures, each lecture lasting about 1 hour.
So go to youtube and type in the search box: Finite Element NPTEL
:)
RE: Learning The FE Method - Any Advice?
From there, you can try building a statically indeterminate truss structure and solving for the forces.
After you've gone that far, you may want to try writing a simple program in Matlab to solve some 2-d or 3-d problems.
Good luck!
RE: Learning The FE Method - Any Advice?
RE: Learning The FE Method - Any Advice?
Thanks for advice.
RE: Learning The FE Method - Any Advice?
RE: Learning The FE Method - Any Advice?
The other replies you got all have good info; I especially recommend doing simple analyses that you can check by hand calcs. This, by the way, is also applicable to more complex analyses - always try to check you results using hand calculations, even if only to obtain order-of-magnitude figures. Another important check is to plot the displaced shape of the structure. If it does not correspond to reality then you know there is a problem.
Regards
Andries
RE: Learning The FE Method - Any Advice?
RE: Learning The FE Method - Any Advice?
Chris
www.value-design-consulting.co.uk
RE: Learning The FE Method - Any Advice?
A First Course in the Finite Element Method by Daryl L. Logan
Wrote simple codes in Matlab and applied them to each problem in the exercise. It was a good learning experience.
Thanks
YSM