Continuum Distribution vs Structural Distribution

[Fea_pather]

I intend to use Distribution coupling in my model to connect a RP to a surface. But I am not sure if I should use Continnum Distribution coupling or Structural Distribution coupling?

 

[Vishakh_Rajendran]

Hello,

Continuum Distribution coupling is primarily used with solid elements. Structural Distribution coupling is primarily used for structural elements (such as beams and shells)

The Reference point has 6 DOF’s but the cloud nodes (if solid) have 3 DOFs. So, in a Continuum distribution, the displacement and the rotation of the RP is coupled to only the displacement of the cloud nodes (Moments applied at the RP are transferred as equivalent force distributions at the coupled solid nodes). But, in a Structural distribution coupling, the displacement and the rotation of the RP is coupled to both the translation and rotation of the cloud nodes.

Best Regards,

Vishakh Rajendran.

 

[FEA way]

Continuum distributing coupling transfers only forces, not moments in the coupling nodes. It's sufficient for solid elements since their nodes don't have rotational DOFs. But in the case of shell and beam elements (whose nodes have rotational DOFs), it's recommended to use structural coupling type so that moments are also transferred. This works significantly better e.g. when modeling 1D bolts connecting shell parts.