Static Modal Analysis

Altair Forum User
Altair Forum User
Altair Employee
edited October 2020 in Community Q&A

I have a model where there is pretension in the bolts and hold down loads applied to the model. Then I want to run a modal analysis with these loads applied. How is it done in Optistruct? Is it done in two loadsteps? Also, as I have a linear static and well as a modal analysis to be done to the model, what solution card should be used?

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Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited February 2015

    Hi,

     

    You may need two subcases. First would be the linear static subcase where pretension is referred.

     

    Second subcase will be the modal analysis subcase. Here you refer the first static subcase in STATSUB(PRELOAD).

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  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited July 2015

    Hi,

     

    I would like to ask for an advice in solving a simmilar problem, with this difference, that I would like to find normal modes of a structure after non-linear static analysis (with contacts). Is it possible to run this sequence of analyses in OptiStruct: nonlinear statics --> normal modes?

     

    Best regards,

    Jakub

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