Composite Shuffle Optimization with plys not in 45 -45° angle

Merula_20758
Merula_20758 Altair Community Member
edited October 2020 in Community Q&A

Hey all,

 

currently I am working on a composite optimization process that involves no 45 and -45° plies.

What I experienced was, that with the step 3 (shuffle optimization), optistruct did not consider my constraint of maximum ply successor. Is this a knows issue?

Additionally, why can't we define pairing constraints between other plies than the 45 and -45° ? Is there a physical reason why you would do that just with 45 and -45 ?

 

Thanks and best regards  :)/emoticons/default_smile.png' srcset='/emoticons/smile@2x.png 2x' title=':)' width='20' />

 

Merula

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited February 2018

    Hi @Merula

     

    Could you please the .out file of shuffling part?

     

    Pairing 45 and -45 reduces in-plane shear stress. 

  • Merula_20758
    Merula_20758 Altair Community Member
    edited November 2020

    Sure. .out attached... we noticed that the constraint was violated, so we increased it to see if it would have any results...

    I attached the .html as well for you to see what changes with every iteration...

    Unfortunatly I cant share the .fem file.

    Thanks Prakash.

    Unable to find an attachment - read this blog

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited February 2018

    Hi @Merula

     

    Optimization finished in two iterations and from .out file I couldn't find anything. 

     

    Is it possible to share the model file?

  • Merula_20758
    Merula_20758 Altair Community Member
    edited February 2018

    I will create an academic example I can share, which I will send to you shortly. Thanks

  • Merula_20758
    Merula_20758 Altair Community Member
    edited November 2020

    As promised, here are the files.

    Unable to find an attachment - read this blog

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited February 2018

    Hi @Merula

     

    If you look at the stack after shuffling, only 0, 90 plies followed MAXSUCC rule but rest were ignored (0, 60). This is intended. The current mechanism accepts only 0/90/45/-45

     

    Developers are already working on in to make a more robust optimization tool.

  • Merula_20758
    Merula_20758 Altair Community Member
    edited February 2018

    Hi @Prakash Pagadala,

     

    as far as I understood this, maxsucc is  a constraint from manufacturing side... Why is it limited to 0 90 45 -45 ? Is there a physical reason for this or just a TODO in the feature list?

     

    Best regards

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited February 2018

    Well, maybe this how it was programmed at the beginning. Proposed, In next version shuffling with MAXSUCC constraint will support all angles. 

  • Merula_20758
    Merula_20758 Altair Community Member
    edited February 2018

    Thanks for this clarification. Looking forward to this update.

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2019

    Is this still the case in Altair 2019 (Optistruct 2019) i.e. if I have a stack with -30/30/90 plies will it ignore the MAXSUCC constraint completely and not be able to pair +/-30 plies?