COMSOL 6.3 - The Phase-Field Damage Interface

The multiphysics interface (

) combines Solid Mechanics and Phase Field in Solids interfaces to model the evolution of damage and cracks in deforming solids.

The coupling occurs on the domain level, where the driving force for damage depends on the state of deformation in the solid, which governs the evolution of the phase field. In turn, the phase field determines the degradation of the solid properties in the damaged regions.

The interface can be used for stationary and time-dependent analyses in 3D, 2D, and 2D axisymmetric domains.

When a predefined interface is added from the branch (

) of the or windows, the and interfaces are added to the Model Builder.

In addition, the node is added, which automatically includes the multiphysics coupling.

On the Constituent Physics Interfaces

•

The Solid Mechanics interface is described in The Solid Mechanics Interface.

•

The Phase Field in Solids interface is described in The Phase Field in Solids Interface.

Settings for Physics Interfaces and Coupling Features

When physics interfaces are added using the predefined couplings, for example , specific settings are included with the physics interfaces and the coupling features.

However, if the physics interfaces are added one at a time, followed by the coupling features, these predefined settings are not automatically included.

For example, if single and interfaces are added, an empty node appears in the model tree. You can choose from the available coupling features, but the settings in the constituent interfaces are not modified.

Table 15-11: Modified Settings for the Phase-Field Damage interface.
Physics Interface or Coupling Feature	Modified Settings
Solid Mechanics	For the Solid Mechanics interface, under Structural Transient Behavior, the Structural transient behavior is set to Quasistatic.
Phase Field in Solids	For the Phase Field in Solids interface, a Phase Field Model node is added by default with a Quadratic potential function.
Phase-Field Damage	The Domain Selection is the same as that of the participating physics interfaces. The corresponding Solid Mechanics and Phase Field in Solids interfaces are preselected in the Coupled Interfaces section.