Surface Based Coupling (Abaqus)

When you are working with Abaqus as your solver, you can use the Surface Based Coupling command to create a coupling between a reference node and a group of nodes called the coupling nodes. You can create a Surface Based Coupling to constrain a group of nodes to the rigid body motion of a single node. For example, you can use a *KINEMATIC type of Surface Based Coupling to define a twisting motion without constraining the radial motion.

With Surface Based Coupling, you select a reference node and use a Region to define the surface that contains the nodes that you want to couple. The software automatically selects the appropriate coupling nodes on that surface based on that Region and an optional Influence Radius.

Choosing the type of coupling to create

You can use the Coupling Type option in the Surface Based Coupling dialog box to control the type of coupling constraint the software creates.

• Select *KINEMATIC to create kinematic constraints that eliminate degrees-of-freedom at the coupling nodes. This constrains the motion of the coupling nodes to the rigid body motion of the reference node.Note: You should not apply any additional constraints or boundary conditions to the coupling nodes involved in a *KINEMATIC coupling constraint.

• Select *DISTRIBUTING to constrain the motion of the coupling nodes to the translation and rotation of the reference node. The constraint distributes loads so that the resultants of the forces (and moments) at the coupling nodes are equivalent to the forces and moments at the reference node. With the *DISTRIBUTING option, you can control the default weight distribution at the coupling nodes.For more information, see Distributing coupling elements in the Abaqus Theory Guide.

Defining a reference node and a surface

In a Surface Based Coupling definition, you must select a reference node and the surface on which the coupling nodes are located.

• You can select only one node as the reference node. The reference node is effectively the control point for the constraint. For a *KINEMATIC type of Surface Based Coupling constraint, the reference node has both translational and rotational degrees-of-freedom.

• You use a Region to define the surface on which the coupling nodes are located. In Abaqus, you can use either an element-based surface or node-based surface to define that surface. In Pre/Post, when you create a region, you can select either Node or Element from the Surface Definition Type list in the New Region dialog box.

Specifying a region of influence

By default, Abaqus uses all the nodes on the specified surface as the coupling nodes. You can also limit the coupling to only those nodes that lie within a spherical region, centered on the reference node, on that surface. You can use the Influence Radius option in the Surface Based Coupling dialog box to specify the radius the software uses to define the influence region.

For more information on defining a region of influence, see Specifying a region of influence in the Coupling constraints topic in the Abaqus Analysis User's Guide.

Note:

A *DISTRIBUTING type of coupling constraint must include at least two coupling nodes.

Specifying a coupling method for *DISTRIBUTING couplings

With *DISTRIBUTING type couplings, you can use the Coupling Method option to control how the software couples the motion of the reference node to the average motion of the coupling nodes.

• Select Continuum to couple the translation and rotation of the reference node to the average translation of the coupling nodes. This constraint distributes the forces and moments at the reference node as a coupling node-force distribution only. No moments are distributed at the coupling nodes.

• Select Structural to couple the translation and rotation of the reference node to the translation and rotation of the coupling nodes. This constraint distributes the forces and moments at the reference node as a coupling node-force and moment distribution.

For more information, see:

• Defining the surface coupling method in the Coupling constraints article in the Abaqus Analysis User's Guide.

• Distributing coupling elements in the Abaqus Theory Guide.

Selecting a weighting method for *DISTRIBUTING couplings

With a *DISTRIBUTING coupling, you can use the Weighting Method list to specify an optional weighting method to modify the default weight distribution at the coupling nodes. With the Uniform weighting method, the software sets all weight factors uniformly to a value of 1.0. Other weighting methods allow you to monotonically decrease the weighting factor for a coupling node with its radial distance from the reference node.

For more information, see Weighting methods in the Coupling constraints article in the Abaqus Analysis User's Guide.

Associated Abaqus keywords

When you export or solve your model, the software uses the options you specify in the Surface Based Coupling dialog box to define the *COUPLING keyword and either the *KINEMATIC or *DISTRIBUTED keyword in your Abaqus input file. For more information, see Coupling constraints in the Abaqus Analysis User's Manual and *COUPLING,*KINEMATIC, or *DISTRIBUTING in the Abaqus Keywords Reference Guide.

Where do I find it?

Application	Pre/Post
Prerequisite	An active Simulation file with Abaqus as the specified solver
Command Finder	Surface Based Coupling
Simulation Navigator	Under the active solution, right-click Simulation Objects→New Simulation Object→Surface Based Coupling

Learn more

Contact and glue overview (Abaqus)

Comparison of general contact and contact pair (Abaqus)

Contact with Clearance (Abaqus)

Bolt Contact with Clearance (Abaqus)

Tie Surface (Abaqus)

Modeling cohesive behavior in Abaqus contact analyses

Defining damage modeling for Abaqus cohesive behavior

Removing elements and contact pairs (Abaqus)

Automatic face pairing

Quick links

Command reference

Pre/Post video examples

Bulk Entry Descriptions

Simcenter 3D tutorials

Browse Simcenter 3D help by product area

Surface Based Coupling (Abaqus), Simcenter 3D 2021.1 Series

© 2020 Siemens

window.mainLanguage="en_US"

window.delivId=""

window.projectId=""

MathJax.Hub.Config({ TeX: { extensions: ["autoload-all.js"] }, tex2jax: { displayMath: [ ] }, "SVG": { scale: 125 } });