Specifying thermorheologically simple (TRS) temperature dependence for time domain viscoelasticity

You can define the shift function either by entering parameters for the Williams-Landel-Ferry approximation or by using user subroutine UTRS. For more information on temperature effects in time domain viscoelasticity, see Time domain viscoelasticity.

  1. Create a time domain viscoelastic material as described in Defining time domain viscoelasticity.”

  2. From the Suboptions menu in the Edit Material dialog box, select Trs.

    The Suboption Editor appears.

  3. Click the arrow to the right of the Shift function field, and select the option of your choice.

    • Select WLF to define the shift function using the Williams-Landel-Ferry approximation.

    • Select User Subroutine UTRS to define the shift function using user subroutine UTRS.

  4. If you selected WLF from the list of Shift function options, enter the required data in the Data table:

    Theta 0

    Reference temperature, θ0.

    C1

    Calibration constant, C1.

    C2

    Calibration constant, C2.

    You may need to expand the dialog box to see all the columns in the Data table. For detailed information on how to enter data, see Entering tabular data.

  5. Click OK to return to the Edit Material dialog box.