Defining Thermal Properties

To define the material behavior in response to changes in the solid temperature, you specify the reference temperature at which the thermal strain is assumed to be zero and the coefficients that define the material thermal expansion.

In the solid physics continuum, activate either the Specified Temperature or the Finite Element Solid Energy model, as required.
For guidelines, see Selecting Solid Stress Physics Models.
Depending on the material type (elastic or hyperelastic), define an appropriate material law and the material mechanical properties, as described in the sections:
- Defining Linear Elastic Materials
- Defining Hyperelastic Materials

Add the following models to the existing material law models:


Group box	Model
Optional Models	Thermal Expansion
Thermal Expansion Material Models	Activate one of the following: To model materials that have the same thermal properties in all directions, activate Isotropic Thermal Expansion. For hyperelastic materials, this is the only option available. To model materials that have independent thermal properties along three mutually-orthogonal directions, activate Orthotropic Thermal Expansion. To model materials that have independent thermal properties in all directions, activate Anisotropic Thermal Expansion.

Expand the relevant [Physics Continuum] > Models > Solid > [Solid Material] > Material Properties node.
Simcenter STAR-CCM+ adds the relevant thermal properties based on the specified thermal expansion models:
Select the Zero Thermal Strain Reference Temperature node and specify the temperature at which the material thermal strain is assumed to be zero (see Eqn. (4452)).

Specify the remaining properties based on the selected thermal expansion material model:


Material Model	Steps
Isotropic Thermal Expansion	Specify the Thermal Expansion Coefficient. See Eqn. (4514).
Orthotropic Thermal Expansion (only for linear elastic materials)	Expand the Orthotropic Thermal Expansion Coefficients node and specify the three coefficients alpha 1, alpha 2, and alpha 3. See Eqn. (4510).
Anisotropic Thermal Expansion (only for linear elastic materials)	Expand the Anisotropic Thermal Expansion Coefficients node and specify the six components of the thermal expansion coefficients vector. See Eqn. (4504).

Orthotropic or anisotropic properties are defined with respect to a local coordinate system. You specify the local orientation of each solid region using the Regions > [region] > Physics Values > Material Law Orientation node. See Defining Linear Elastic Materials.

For more information, see Material Properties.