FEM ConstraintContact

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Revision as of 15:47, 8 February 2020 by Kunda1 (talk | contribs) (Change section to 'Usage')

FEM ConstraintContact

Menu location
Model → Mechanical Constraints → Constraint contact
Workbenches
FEM
Default shortcut
None
Introduced in version
-
See also
FEM tutorial

Description

Creates a FEM constraint for contact between 2 surfaces.

Usage

  1. Click on or choose ModelMechanical Constraints Constraint contact from the FEM dropdown menu.
  2. Select the master face.
  3. Select the slave face.
  4. Enter a contact stiffness.
  5. Enter a friction coefficient.

Limitations

  1. The contact constraint can only be applied to two faces.
  2. Development for multiple contact at once: https://forum.freecadweb.org/viewtopic.php?f=18&t=15699&start=130#p303275

Notes

Tips for modeling

  • from https://forum.freecadweb.org/viewtopic.php?f=18&p=340874#p340494
  • Better use linear elements otherwise calculations are very time consuming
  • master/slave assignment:
    • The larger of the two surfaces should act as the master surface.
    • If the surfaces are of comparable size, the surface on the stiffer body should act as the master surface.
    • If the surfaces are of comparable size and stiffness, the surface with the coarser mesh should act as the master surface.

CalculiX

  • A very detailed CalculiX contact example. (link)
  • A very cool example found in the FreeCAD German subforum. (link)