Remote Force

The remote force boundary condition is used apply a force to a face or edge of a structure from a remote point. The remote force is the analogous boundary condition of the remote displacement boundary condition for forces.

In addition to a standard force boundary condition a remote force boundary condition also allows to apply a moment to a face or an edge.

When the deformation behavior is set to deformable, the application of the remote displacement boundary condition doesn’t add any stiffness to the associated entity, while with the selction undeformable the entity is sets to be rigid.

There are also some limitations, mainly the fact that this is a linear boundary condition and valid only if small displacements and rotations occur in the area of the applied entity and the remote point itself.

Force

The user defines for each global coordinate directions the force that should be applied. Each value can either be defined by a scaler value, a function or a table. For function or table data the value may depend on time (or frequency in case of a harmonic analysis) and the spatial coordinates.

Moment

For each rotational direction the user can define a moment that is applied to the assigned entities. The input methods and possible dependencies are the same as for the forces.

Remote Point

Here the user defines the coordinates of the external point on which the forces and moments are applied. The coordinates are given in the global coordinate system of the mesh.

Deformation behavior

This property defines if the applied associated entities (edges or faces) may deform or if they are assumed to be rigid.

If the setting deformable is selected, no additional stiffness is generated on the applied entities. The remote point is connected to the entities by a RBE3-constraint. This means that the produced linear relations are such as the forces of the remote point are distributed to the nodes of the assigned entities proportionally to their distance to the center of gravity of the assigned entities.

If the setting undeformable is selected the entity behaves like a rigid part. The connection of the point and the entities is a multi-point constraint which blocks all relative displacements between the affected nodes.

Hint

If the deformable option is used and the number of nodes of the assigned entities is large (>1000), it is advised to use either the MUMPS or PETSC solver instead of Multfront since the performance of Multfront is not optimal for this kind of equations.