Mesh Motion

Mesh Motion = {char_string}

Description / Usage

This card is required for each material section in the Problem Description File even if a moving mesh problem is not being solved. It is used to specify the method which prescribes the movement of nodes within the mesh. Valid options for {char_string} are:

ARBITRARY	This option triggers the implicit pseudo-solid domainmapping technique using the constitutive equation designated in the corresponding file.mat (see Material File description); with this technique, the boundaries of the domain are controlled by distinguishing conditions coupled with the problem physics, and the interior nodes move independently of the problem physics.
LAGRANGIAN	This option triggers coupling the motion of nodes on the interior of the domain to the deformation of an elastic solid. If the solid is incompressible, this technique uses a pressure (Lagrange multiplier) to couple the solid deformation and the local solvent concentration.
DYNAMIC_LAGRANGIAN	This option triggers coupling the motion of nodes on the interior of the domain to the deformation of an elastic solid, including solid inertia. If the solid is incompressible, this technique uses a pressure (Lagrange multiplier) to couple the solid deformation and the local solvent concentration. Together with the equation term multiplier on the mass matrix (see EQ card) and a “transient” specification on the Time Integration Card, this option will invoke a Newmark- Beta time integration scheme for the inertia term in the R_MESH equations.
TOTAL_ALE	This option allows motion of nodes on the interior of the domain of a solid region to be independent of the material motion. TALE is an acronym for “Total Arbitrary Lagrangian Eulerian” mesh motion. This is typically used in elastic solids in which large scale deformation makes motions under the LAGRANGIAN option unmanageable. If the solid is incompressible, this technique uses a pressure (Lagrange multiplier) to couple the solid deformation and the local solvent concentration. Invoking this option requires mesh equations and real solid equations, as described on the EQ card. Other relevant cards that are often used with this option are KINEMATIC_DISPLACEMENT boundary condition, DX_RS, DY_RS, DZ_RS boundary conditions, FORCE_RS, FLUID_SOLID_RS, and others. See references for more detailed usage procedures.

Examples

The following is a sample card that sets the mesh motion scheme to be arbitrary:

Mesh Motion = ARBITRARY

Technical Discussion

For the TOTAL_ALE mesh motion option we must supply elastic properties and solid constitutive equations for both the mesh and the real solid. It is best to consult the example tutorials cited below for details.

References

GT-005.3: THE NEW TOTAL-ARBITRARY-LAGRANGIAN-EULERIAN (TALE) CAPABILITY and its applicability to coating with/on deformable media, August 6, 1999, P. R. Schunk

GT-006.3: Slot and Roll coating with remeshing templates and tutorial for GOMA and CUBIT/MAPVAR, August 3, 1999, R. R. Lober and P. R. Schunk