Radioss optimization to minimize compliance

Simon Križnik
Simon Križnik Altair Community Member
edited October 2020 in Community Q&A

Hi,

 

I am running Radioss topology optimization to minimize compliance with constrained volume fraction. The plate has all translations constrained on the left and right edges and mass is added. The expectation was that reinforcing ribs would connect supports across left-right direction, which was confirmed with Optistruct. However Radioss optimization produced counterintuitive result with reinforcements running along supports. From the .eslout file it became evident the objective function was minimize maximum compliance; in Optistruct run the objective was minimize compliance. 

 

How to set up Radioss optimization to get results similar to Optistruct? The solver decks are attached bellow if anyone would like to look into.

 

<?xml version="1.0" encoding="UTF-8"?>optistruct.gif

<?xml version="1.0" encoding="UTF-8"?>radopt.gif

Unable to find an attachment - read this blog

Tagged:

Answers

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited October 2017

    Hi Ivan,

    We are working on your query and will update you very soon.

  • Simon Križnik
    Simon Križnik Altair Community Member
    edited November 2017

    Hi,

     

    a gentle reminder: is there anything I can help you with to resolve this query?

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2017

    Hi,

    There is some mismatch with the compliance in OptiStruct and RADIOSS optimization out files.

    We are checking with the experts and  will update as soon as possible.

  • Simon Križnik
    Simon Križnik Altair Community Member
    edited November 2017

    Hi,

     

    thanks for update.

    I would also like to know how to setup radopt syntax so optimization parameters (DOPTPRM) and shres ouput requests are passed down with /BULK to OptiStruct deck during design optimization.

     

    The following had no influence on the run:

    /BULK/IO/1

    OUTPUT,SHRES,ALL
    /BULK/DATA/2
    DOPTPRM,DESMAX,200,DISCRETE,4.0

  • Altair Forum User
    Altair Forum User
    Altair Employee
    edited November 2017

    Hi Ivan,

     

    We were working on your model and it seems to be an issue. We are taking up this to the development team and will be fixed in the next release.