Zero-Length Spring Creating

Omer Faruk GUMUS_21691
Omer Faruk GUMUS_21691 Altair Community Member
edited October 2020 in Community Q&A

Hi,

https://altairuniversity.com/learning-library/v_e_spring-element-type-8/   

In the first example of the video on the link above, instructor has two cylinder laid in same axis. Each cylinder has one RBODY with their whole nodes. And RBODY's independent nodes weren't created using calculated nodes. 
Then, how did he create 'zero-length' spring as he told in the video ??

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Answers

  • Pranav Hari
    Pranav Hari Altair Community Member
    edited December 2018

    Hi Omer Faruk GUMUS

     

    And RBODY's independent nodes weren't created using calculated nodes

     Yes, it is created using calculate node option only

     

    The zero length spring (type 8) is created by connecting the 2 independent node of the rigids.

     

  • Omer Faruk GUMUS_21691
    Omer Faruk GUMUS_21691 Altair Community Member
    edited December 2018

    Thanks Mr. Pranav.

    I actually wondered about if a mass and inertia are unnecessary just only when I create the spring by two independent nodes. In the video , the instructor could write '0' for mass and inertia in hypercrash interface. But it is not possible to set 0 value for mass and inertia in hypermesh interface , if you try, you'll get * sign with red color.  So, so zero length means that mass and inertia are not taken into consideration ???

  • Pranav Hari
    Pranav Hari Altair Community Member
    edited December 2018

    Hi Omer Faruk GUMUS

     

    Spring type 8 is a six degrees of freedom spring: three translations and three rotations. It is often used to model a joint connection between two parts.

     

     

    So, so zero length means that mass and inertia are not taken into consideration ???

    You can even assign mass and inertia to a type 8 spring if you want to study the load conditions. It depends on the application whether to use it or not. In this case we are not assigning because we are considering for a joint and the DOFs are of interest.

     

    Please check the Radioss theory manual for more details regarding the type 8 spring

     

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    <?xml version="1.0" encoding="UTF-8"?>image.thumb.png.9d3dddfb87d8ddddd5059c5f375bc882.png

     

     

    Thanks