Shrinkage and Swelling
The Shrinkage and Swelling multiphysics coupling node () is used to couple the Solid Mechanics interface and the Transport in Solids interface.
The volumetric strain caused by the species transport in the solid reads
where ΩVc is the volumetric coefficient of swelling, c is the species concentration, and cref is the strain-free reference concentration.
For a large strain formulation, the volume change reads
When the linear coefficient of swelling is used, the strain resulting from swelling and shrinkage reads
and for large strain formulation, the deformation gradient reads
where the linear coefficient of swelling, Ωc, is an isotropic or diagonal tensor.
Settings
The Label is the multiphysics coupling feature name. The default Label (for the first multiphysics coupling feature in the model) is Shrinkage and Swelling 1.
The Name is used primarily as a scope prefix for variables defined by the coupling node. Refer to such variables in expressions using the pattern <name>.<variable_name>. In order to distinguish between variables belonging to different coupling nodes or physics interfaces, the name string must be unique. Only letters, numbers, and underscores (_) are permitted in the Name field. The first character must be a letter.
The default Name (for the first multiphysics coupling feature in the model) is sas1.
Domain Selection
The domain selection is empty by default. Only domains that have Linear Elastic Material, Nonlinear Elastic Material, or Hyperelastic Material selected in the Solid Mechanics interface are available.
Coupled Interfaces
This section defines the physics involved in this multiphysics coupling. The Transported quantity and Solid mechanics lists include all applicable physics interfaces.
You can select None from either list to uncouple the coupling node from a physics interface. If the physics interface is removed from the Model Builder (for example, Solid Mechanics is deleted), then the list defaults to None as there is nothing to couple to.
Shrinkage and Swelling Properties
From the Specify list select how the swelling coefficient is entered — Volumetric coefficient or Linear coefficient.
Enter a Reference value cref. This is the concentration at which there are no strains due to shrinkage or swelling.
When Volumetric coefficient is selected, enter the volumetric Swelling coefficient ΩVc.
When Linear coefficient is selected, select Isotropic or Diagonal from the list to enter one or more components for the swelling tensor Ωc. For anisotropic swelling, the axis orientations are given by the coordinate system selection in the Solid Mechanics node to which it contributes.
Enter the Molar mass Mc.
The units for the input depend on the settings in the Transported Quantity section.
Select the Include mass added by transported quantities checkbox to include the mass of the transported species in dynamic analyses, and when using mass proportional loads. The additional mass from the species will also be included when calculating the mass properties.