12.12.1 Defining an acoustic medium

You can define an acoustic medium to model sound propagation problems in a purely acoustic analysis or in a coupled acoustic-structural analysis. For more information, see “Acoustic medium,” Section 26.3.1 of the Abaqus Analysis User's Guide.

To define an acoustic medium:

From the menu bar in the Edit Material dialog box, select OtherAcoustic Medium.
(For information on displaying the Edit Material dialog box, see “Creating or editing a material,” Section 12.7.1.)
Display the Bulk Modulus tabbed page.
Toggle on Use temperature-dependent data to define the bulk modulus as a function of temperature.
A column labeled Temp appears in the Data table.
Click the arrows to the right of the Number of field variables field to increase or decrease the number of field variables on which the bulk modulus depends.
Enter the following data in the Data table:
Bulk Modulus
Bulk modulus, . (Units of FL^–2.) For more information, see “Defining an acoustic medium” in “Acoustic medium,” Section 26.3.1 of the Abaqus Analysis User's Guide.
Temp
Temperature.
Field n
Predefined field variables.
For detailed information on how to enter data, see “Entering tabular data,” Section 3.2.7.
If desired, display the Volumetric Drag tabbed page, and toggle on Include volumetric drag. For more information, see “Volumetric drag” in “Acoustic medium,” Section 26.3.1 of the Abaqus Analysis User's Guide.
If you want to omit volumetric drag data, skip to Step 11.
Toggle on Use temperature-dependent data to define the volumetric drag data as a function of temperature.
A column labeled Temp appears in the Data table.
Click the arrows to the right of the Number of field variables field to increase or decrease the number of field variables on which the volumetric drag data depend.
Enter the following data in the Data table:
Volumetric Drag
Volumetric drag coefficient. (Units of FTL^–4.)
Frequency
Frequency. (Cycles/time.) Frequency dependence is active only during frequency domain procedures in Abaqus/Standard.
Temp
Temperature.
Field n
Predefined field variables.
For detailed information on how to enter data, see “Entering tabular data,” Section 3.2.7.
Click OK to close the Edit Material dialog box. Alternatively, you can select another material behavior to define from the menus in the Edit Material dialog box (see “Browsing and modifying material behaviors,” Section 12.7.2, for more information).