*ADAPTIVE MESH CONSTRAINT

Specify constraints on the motion of the mesh for an adaptive mesh domain.

Warning: Abaqus/Explicit does not admit jumps in mesh displacement. If no amplitude is specified, Abaqus/Explicit will ignore the user-supplied displacement value and enforce a zero mesh motion constraint.

This option is used to prescribe independent mesh motion for nodes in an adaptive mesh domain or to define nodes that must follow the material. It can be used only in conjunction with the ADAPTIVE MESH option.

This page discusses:

See Also
*ADAPTIVE MESH
In Other Guides
Defining ALE Adaptive Mesh Domains in Abaqus/Explicit
Defining ALE Adaptive Mesh Domains in Abaqus/Standard
UMESHMOTION

ProductsAbaqus/StandardAbaqus/ExplicitAbaqus/CAE

TypeHistory data

LevelStep

Abaqus/CAEDisplacement and velocity adaptive mesh constraints are supported in the Step module.

Optional parameters

AMPLITUDE

This parameter is relevant only when some of the variables being prescribed have nonzero magnitudes. Set this parameter equal to the name of the amplitude curve defining the magnitude of the prescribed mesh motion (Amplitude Curves).

CONSTRAINT TYPE

Set CONSTRAINT TYPE=SPATIAL (default) to prescribe mesh motions that are independent of the underlying material.

Set CONSTRAINT TYPE=LAGRANGIAN to define nodes that must follow the material.

OP

Set OP=MOD (default) to modify existing mesh constraints or to add mesh constraints to degrees of freedom that were previously unconstrained.

Set OP=NEW if all mesh constraints that are currently in effect should be removed. To remove only selected mesh constraints, use OP=NEW and respecify all mesh constraints that are to be retained.

The OP parameter must be the same for all uses of the ADAPTIVE MESH CONSTRAINT option within a single step.

TYPE

Set TYPE=DISPLACEMENT (default) to prescribe mesh displacement.

Set TYPE=VELOCITY to prescribe mesh velocity.

USER

This parameter applies only to Abaqus/Standard analyses.

Include this parameter if the mesh motion is to be defined in user subroutine UMESHMOTION. This parameter cannot be used when CONSTRAINT TYPE=LAGRANGIAN.

Data lines to prescribe mesh motions that are independent of the material (CONSTRAINT TYPE=SPATIAL)

First line

  1. Node number or node set label.

  2. First degree of freedom constrained. This value is ignored when the USER parameter is specified.

  3. Last degree of freedom constrained. This field can be left blank if the mesh must be constrained only in one direction. This value is ignored when the USER parameter is specified.

  4. Actual magnitude of the mesh motion (displacement or velocity). This magnitude will be modified by an amplitude specification if the AMPLITUDE parameter is used. This value will be ignored in an Abaqus/Explicit analysis if TYPE=DISPLACEMENT, no AMPLITUDE specification is provided, and this value is nonzero.

Repeat this data line as often as necessary to specify mesh constraints at different nodes and degrees of freedom.

Data lines to define nodes that must follow the material (CONSTRAINT TYPE=LAGRANGIAN)

First line

  1. Node number or node set label.

Repeat this data line as often as necessary. Up to 16 entries are allowed per line.