The Free Shape Domain feature () can be added from the model tree under Component>Definitions using the Shape Optimization context menu. It sets up a smoothing equation for the domains in its selection, but it does not add any control variables, so unless a Polynomial Boundary or a Free Shape Boundary are added, the shape of the geometry will not change.

Boundaries will be considered fixed, if they are not part of a Polynomial Boundary, Free Shape Boundary, or Symmetry/Roller boundary. The interior boundaries of the Free Shape Domain feature are never fixed.

The Free Shape Domain feature includes the following settings:

For the mesh smoothing, choose smoothing type from the Mesh smoothing type list: Laplace (the default), Winslow, Hyperelastic, or Yeoh. For Yeoh, also enter a Stiffening factor C2 (default: 10). See Smoothing Methods in the COMSOL Multiphysics Reference Manual for more information.

Enter the initial deformation in the dx fields (default: 0 for all components).