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ULiege - Aerospace & Mechanical Engineering

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doc:user:elements:contact:interactions

# Contact Interactions

Contact elements are generated on the mesh using Interactions described below, in the same way as volume elements.

## Rigid-Defo contact

Interaction between a rigid body (die), meshed or not, and a deformable meshed entity.

ci = RdContactInteraction(number)
ci.setTool(gObject1)
ci.push(gObject2)
ci.setSmoothNormals(bool)
interactionset.add(ci) 

where

 number number of the Interaction gObject1 Reference of a geometric object (facetised contact), meshed or not gObject2 Reference of a meshed geometric object prp Properties of contact elements to generate setTool Rigid tools setSmoothNormals(bool) Facetised tool = True (default) : continuous normal - projection on a MultiProjWire or MultiprojSkin = False : discontinuous normal - projection on Wire or Skin

## Defo-Defo contact

Interaction between two different deformable meshed entities. By default, contact is double in two steps. First, the nodes from the second body are considered as slaves of the first body, then, nodes from the first are considered as slaves of the second.

ci = DdContactInteraction(number)
ci.setTool(gObject1)
ci.push(gObject2)
ci.setSmoothNormals(bool)
ci.setGeoContact()
ci.setSinglePass()
interactionset.add(ci) 

where

 number number of the Interaction gObject1, gObject2 Reference of a meshed geometric object prp Properties of contact elements to generate setTool “Preferential” tool (tool in one step and for thermomechanical contact) setSmoothNormals(bool) Facetised tool = True (default) : continuous normal - projection on a MultiProjWire or MultiprojSkin = False : discontinuous normal (normal not smoothed, might lead to convergence issue)- projection on Wire or Skin setSinglePass() Contact in one step (Nodes from second body are slaves of the first one) setGeoContact() Contact between nodes of the second body and a spline rebuild from nodes of the first body

## Auto - Contact

Interaction between two parts of a same meshed body.

ci = ScContactInteraction(number)
ci.push(gObject1)
ci.setSmoothNormals(bool)
interactionset.add(ci) 

where

 number number of the Interaction gObject1 Reference of a meshed geometric object prp Properties of contact elements to generate setSmoothNormals(bool) Facetised tool = True (default) : continuous normal - projection on a MultiProjWire or MultiprojSkin = False : discontinuous normal - projection on Wire or Skin

## Rigid-Defo contact driven with a force

Interaction between a rigid body (die) and a deformable meshed entity. When this contact interaction is instantiated, the rigid body gets a node to impose force monitoring. Consequently, the body has rigid body modes in translation.

ci = FdRdContactInteraction(number)
ci.setTool(gObject1)
ci.push(gObject2)
ci.setSmoothNormals(bool)
interactionset.add(ci) 
 number number of the Interaction gObject1 Reference of a geometric object (facetised contact), meshed or not gObject2 Reference of a meshed geometric object prp Properties of contact elements to generate setTool Rigid tools setSmoothNormals(bool) Facetised tool = True (default) : continuous normal - projection on a MultiProjWire or MultiprojSkin = False : discontinuous normal - projection on Wire or Skin