For a general overview, see Define Connections in the Mechanical User's Guide.
Line body to line body contact is subject to the following:
Contact Detection is set to Proximity Based in the Body Interactions Details view.
Edge on Edge is set to Yes in the Body Interactions Details view.
The Interaction Type is defined as Frictional or Frictionless.
LS-DYNA uses the *CONTACT_AUTOMATIC_GENERAL and *CONTACT_AUTOMATIC_SINGLE_SURFACE keywords when a friction or frictionless Body Interaction is scoped to geometry that contains line bodies. The keywords handle contacts between line bodies only, and line bodies to other body types respectively. In the case where the Body Interaction is scoped to only line bodies, then only the *CONTACT_AUTOMATIC_GENERAL keyword is used.
Reinforcement body interaction is supported in the case when only line bodies are scoped to a Body Interaction of Type = Reinforcement. The line bodies will then be tied to any solid body that they intersect. Reinforcement beams will not reinforce Particle bodies. Reinforcement body interactions are not supported for 2D Explicit Dynamics analyses. However for LS-DYNA, Keyword Snippets under Contact Region objects should provide a suitable alternative.
Body Interactions, Contact and Spot Welds are all valid in Explicit Dynamics analyses. Frictional, Frictionless and Bonded body interactions and contact options are available. Conditionally bonded contact can be simulated using the breakable property of each bonded region. Spot Welds can also be made to fail using the breakable property. Contact Regions and Spot Welds cannot be scoped to Particle bodies (for LS-DYNA only Contact Regions of type No Separation or Rough cannot be scoped to Particle bodies). Bonded Contact is not supported for Particle reference frames.
Beam connections are not supported for Explicit Dynamics analyses. The Contact Tool is also not applicable to Explicit Dynamics analyses.
For LS-DYNA, bonded body interactions are not supported. Also, Contact Region objects with Auto Asymmetric Behavior or just Asymmetric Behavior are treated the same. Symmetric Behavior will create a _SURFACE_TO_SURFACE keyword for the contact and an Asymmetric Behavior will create a _NODES_TO_SURFACE keyword.
Bonded contact is not supported in an Explicit Dynamics analysis for bodies that have their Reference Frame set to Eulerian (Virtual). A solver warning is shown to let the user know that such bodies will be ignored for bonds. Bonded contact is not support in a 2D Explicit Dynamics analysis.
To avoid hourglassing problems, remote points can be used if there are only a few nodes active in the bond definition.
Bonds are not recommended for joining tetrahedral meshes. Use multibodied parts or remote points instead.
By default, a Body Interaction object will be automatically inserted in the Mechanical application tree and will be scoped to all bodies in the model. This object activates frictionless contact behavior between all bodies that come into proximity during the analysis.
More information is available in the following sections: