Structural Engineering or FEA Freeware ?

Discussion in 'Software' started by Erwan, Mar 28, 2015.

  1. Erwan
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    Erwan Senior Member

    Hi Everybody,

    In addition to Michlet FreeShip and XFOIL, imho, it would be interesting to identify a similar freeware for structural engineering.
    I noticed that whatever is your project, you always need to iterate between CFD solutions and structural possibilities.
    For instance, I would like to make some comparison between a tube an an I-beam. with mostly flexion plus compression and a little amount of twist.

    Best regards

    EK
     
  2. Ad Hoc
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    Ad Hoc Naval Architect

    EK

    If you understand structural theory, this is a simple hand calculation.

    If you don't, then any freeware or otherwise, will simply confuse you with answers you don't fully understand and most likely make an error.
     
  3. upchurchmr
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    upchurchmr Senior Member

    +1 to Ad Hoc.

    The analysts at work often complain that people who think FEA is the solution to all calculation generally apply it wrong and miss the simple physical facts shown by well known hand calculations.
    Basic engineering is more useful.
     
  4. gonzo
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    gonzo Senior Member

    It can be "missing the forest for the trees". Focusing only on the details without comprehending the whole leads to bad design. I think that there is too much focus on FEA and other type of software without the knowledge to interpret the results.
     
  5. TANSL
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    TANSL Senior Member

    Gonzo, partly you are right but you're making a major mistake: FEA is not a software but a method of analysis. I agree with you that, without knowing the existing tools one can not interpret the result and there should not express an opinion.
     
  6. gonzo
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    gonzo Senior Member

    FEA is a method. However, there is software where the user can input a design and it generates a grid with data on stress, strain, etc. That is where no understanding of what the structure does can cause the worst problems. The 3D graphs and tables of data look very professional, but may be meaningless.
     
  7. upchurchmr
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    upchurchmr Senior Member

    Tansl,

    What are you now?
    An English teacher?

    Who are you saying should not express an opinion?

    The OP just asked a question, and your nit picking just muddies the clarity of the answer.
     
  8. TANSL
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    TANSL Senior Member

    upchurchmr, no, I am not an English teacher because, as you can see, I have difficulty expressing myself in that language. I did not want to say anything about the question in the OP because I totally agree with what Ad Hoc and yourself have said. I think that's the right answer and that little more can be added. What I want to clarify here is that one should not confuse a method of calculation and the software to calculate it. I meant that if the method is not known, to the point of confusing method and software, it is risky to interpret the results and that a person who commits this mistake should not express an opinion as to not confuse the OP.
    I think Erwan should focus on the theoretical study, either with FEA or beam theory or three moments method, as you advise him. And that does not mean he should study a particular software. That is the mistake that I wanted to avoid.
    That's all.
     
  9. Alik
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    Alik Senior Member

    There is a belief that magic software exists that will allow to do the analysis and design any boat. CFD and FEA are tools and the answers You get from them depend on many factors, such as level of details for modeling, simplifications, boundary conditions, design loads, strength criteria, etc... CFD is good but only when You can anchor it to the very similar hull with already known performance. With FEA yes one can get some answers, but it will equally mislead or fail on number of tasks.

    I can design boats without both CFD and FEA. But I use both, but only when needed, not for every project.

    [​IMG]
     
  10. Erwan
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    Erwan Senior Member

    Thanks everybody for all these comments

    It's quite a good new, if FEA software is not necessary

    Equations exist, and I have a little math backgroung, so if I was familiar with the topic, I wouldn't hesitate to use them.
    Wether it is hand calculation or software calculations, I guess the adage garbage-in garbage-out remains relevant.
    So I should change the formulation:
    Is there any structural engineering tutorial for tube and I-beam calculations with a step-by step approach, and of course.
    The first step could be a thorough definition of the forces, moments, stress strains, warp and so on..I guess

    Thanks
    EK
     
  11. Ad Hoc
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    Ad Hoc Naval Architect

    Plenty, just Google it. here is one example.
     

    Attached Files:

  12. Erwan
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    Erwan Senior Member

    Thanks AdHoc,

    With Google, for a rookie, the pb is to choose the appropriate workpaper.
    Here is the one I choosed, not pedagogic but the topic is interesting...for me.

    Cheers

    EK
     

    Attached Files:

  13. Erwan
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    Erwan Senior Member

    Thank you again AdHoc,

    Googlizing "Lectures Notes ..." as mentionned on your document, I download all chapters from 1 to 10 in addition to yours.

    That's a great pedagogic document for a rookie, it looks very synthetic and crystal clear.

    Cheers

    EK
     
  14. Ad Hoc
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    Ad Hoc Naval Architect

    Indeed...that's why i thought it appropriate for you.

    Glad it is of use to you.
     

  15. Erwan
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    Erwan Senior Member

    You though very well

    Thanks again

    EK
     
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