1D bar orientarion

Fernando Hernández Alonso_20813
Fernando Hernández Alonso_20813 Altair Community Member
edited November 2020 in Community Q&A

Hi there, 

I'm not sure that I am fully understanding the way bars orientation work. To be honest, I don't understand it at all... 

I attach the model I am currently working on. I would really appreciate it if anyone could explain me the way orientation works and how I should define the four CBEAM's orientation.

To put it in context, the CBEAMs represent steel cables that prevents the undertray to displace more than it should when a distributed load is applied on it. 

*Note that the model attached is a non complete version, because the complete one weighs more than 5MB.

Best Answer

  • Adriano Koga_20259
    Adriano Koga_20259 New Altair Community Member
    edited November 2020 Answer ✓

    Thank you so much! 

    So applying your information to my model... I still don't get how I should define orientation. If x axis is automatically defined from A to B and my cross section is a solid circle defined in Hyperbeam, is it okay if I introduce ycomp=1?

    Fernando,

     

    Y vector should be perpendicular to your x-axis.

    In case of a circle section, the only thing you need to avoid is to have a orientation vector parallel to x-axis (a to b). Defining anything different than that, it should be fine.

Answers

  • Adriano Koga_20259
    Adriano Koga_20259 New Altair Community Member
    edited November 2020

    Beam and Bar elements depend on their orientation to correctly define them.

    The V vector is the orientation vector, and combined with your X axis (always from a to b), you will have your XYZ element system.

    The Y vector of your beam is the one that relates to your beamsection, in case you are defining it in HyperBeam tool.

    image

     

    Your Y vector points to the direction showed by the 'Y' vector here inside the beamsection:

    image

     

    Now when it comes to a Beam, you also can define the stress recovery points in the PBEAM/PBAR. These are the points in the cross-section where you want to have your stresses computed. So you will define points C, D, E and F, with respect to your section local system.

    image

     

    Using a PBEAML makes it easier because it already defines them for you. (look at PBEAML documentation).

    image

     

     

    take a look at Altair Students ebook as it gives you some more infos about modelling.

    https://altairuniversity.com/free-ebooks/free-ebook-practical-aspects-of-finite-element-simulation-a-study-guide/

     

  • Fernando Hernández Alonso_20813
    Fernando Hernández Alonso_20813 Altair Community Member
    edited November 2020

    Beam and Bar elements depend on their orientation to correctly define them.

    The V vector is the orientation vector, and combined with your X axis (always from a to b), you will have your XYZ element system.

    The Y vector of your beam is the one that relates to your beamsection, in case you are defining it in HyperBeam tool.

    image

     

    Your Y vector points to the direction showed by the 'Y' vector here inside the beamsection:

    image

     

    Now when it comes to a Beam, you also can define the stress recovery points in the PBEAM/PBAR. These are the points in the cross-section where you want to have your stresses computed. So you will define points C, D, E and F, with respect to your section local system.

    image

     

    Using a PBEAML makes it easier because it already defines them for you. (look at PBEAML documentation).

    image

     

     

    take a look at Altair Students ebook as it gives you some more infos about modelling.

    https://altairuniversity.com/free-ebooks/free-ebook-practical-aspects-of-finite-element-simulation-a-study-guide/

     

    Thank you so much! 

    So applying your information to my model... I still don't get how I should define orientation. If x axis is automatically defined from A to B and my cross section is a solid circle defined in Hyperbeam, is it okay if I introduce ycomp=1?

  • Adriano Koga_20259
    Adriano Koga_20259 New Altair Community Member
    edited November 2020 Answer ✓

    Thank you so much! 

    So applying your information to my model... I still don't get how I should define orientation. If x axis is automatically defined from A to B and my cross section is a solid circle defined in Hyperbeam, is it okay if I introduce ycomp=1?

    Fernando,

     

    Y vector should be perpendicular to your x-axis.

    In case of a circle section, the only thing you need to avoid is to have a orientation vector parallel to x-axis (a to b). Defining anything different than that, it should be fine.

  • Fernando Hernández Alonso_20813
    Fernando Hernández Alonso_20813 Altair Community Member
    edited November 2020

    Fernando,

     

    Y vector should be perpendicular to your x-axis.

    In case of a circle section, the only thing you need to avoid is to have a orientation vector parallel to x-axis (a to b). Defining anything different than that, it should be fine.

    Thank you so much, Adriano