Use the Thermal Expansion subnode to add an internal thermal strain caused by changes in temperature. The thermal strain depends on the coefficient of thermal expansion (CTE) α, the temperature T, and the strain-free reference temperature Tref as

The Volume reference temperature Tref is the temperature at which there are no thermal strains. As a default, the value is obtained from a Common model input. You can also select User defined to enter a value or expression for the temperature locally.

When using Common model input, you can see or modify the value of the volume reference temperature by clicking the Go To Source button (). This will move you to the Common Model Inputs node under Global Definitions in the Model Builder. The default value is room temperature, 293.15 K.

If you want to create a model input value which is local to your current selection, click the Create Model Input button . This will create a new Model Input node under Definitions in the current component, having the same selection as the current Thermal Expansion node.

From the Temperature T list, select an existing temperature variable from a heat transfer interface. For User defined enter a value or expression for the temperature (the default is 293.15 K). This is the centerline temperature of the beam, controlling the axial part of the thermal expansion.

From the Coefficient of thermal expansion α list, select From material to use the coefficient of thermal expansion from the material, or User defined to enter a value or expression for α.

Enter the Temperature gradient in local y-direction Tgy (in 2D and 3D) and in the Temperature gradient in local z-direction Tgz (in 3D), which affects the thermal bending. If beam cross section dimensions have been defined at Bending stress evaluation points — From section heights, these could be used in an expression containing the temperature difference.

Physics tab with Linear Elastic Material node selected in the model tree:
Attributes>Thermal Expansion