define torsion and radial deflection as constraints

Karshenas Reza
Karshenas Reza Altair Community Member
edited February 2022 in Community Q&A

hi,

I just want to briefly ask you if it is possible to define torsional and radial deflections as constraints for topology optimisation of a shaft or pulley in optistruct? I'd thought maybe I could define them as strains but in help wrote, strains can't be defined as constraints for a topology optimisation. Moreover I don't have any idea about defining a cylindrical coordinate system in constraints to get a torsional and radial stains. 

Answers

  • Adriano A. Koga
    Adriano A. Koga
    Altair Employee
    edited February 2022

    You can just create a 'static displacement' response and pick your nodes and define the DOF desired.

    Note that the DOF is based in the nodal system, which can be changed under the 'Systems'. You can assign a local system, cylindrical, for example, and now the DOF is based in this local coordinate system.

     

    1) create a local coordinate system (cylindrical)

    2) assign this system to your nodes of interest

    3) create a 'static displacement' response, selecting the node and DOF desired

    4) create a design constraint with the target/limits necessary

     

  • Karshenas Reza
    Karshenas Reza Altair Community Member
    edited February 2022

    You can just create a 'static displacement' response and pick your nodes and define the DOF desired.

    Note that the DOF is based in the nodal system, which can be changed under the 'Systems'. You can assign a local system, cylindrical, for example, and now the DOF is based in this local coordinate system.

     

    1) create a local coordinate system (cylindrical)

    2) assign this system to your nodes of interest

    3) create a 'static displacement' response, selecting the node and DOF desired

    4) create a design constraint with the target/limits necessary

     

    Got it. Thanks. :)

  • Karshenas Reza
    Karshenas Reza Altair Community Member
    edited February 2022

    thanks for tipps. Now can you please help me again? how can I assign local coordinate system to nodes? 

  • Adriano A. Koga
    Adriano A. Koga
    Altair Employee
    edited February 2022

    thanks for tipps. Now can you please help me again? how can I assign local coordinate system to nodes? 

    create your system in 'systems' panel.

     

    once they're created, in the same panel, go to 'assign'.

    Select your new system, pick the nodes you want, and the user 'set displacement'.

    These nodes now are defined in this local coordinate system, meaning their axis are defined by your LCS. (radius, theta and z, for cylindrical)