You can create an inward volume acceleration load to specify a volume acceleration at a vertex or node on the boundary of an acoustic medium. (For more information, see “Loads,” in “Acoustic, shock, and coupled acoustic-structural analysis,” Section 6.10.1 of the Abaqus Analysis User's Guide.)
To create or edit an inward volume acceleration:
Display the inward volume acceleration load editor using one of the following methods:
To create a new inward volume acceleration load, follow the procedure outlined in “Creating loads,” Section 16.8.1 (Category: Acoustic; Types for Selected Step: Inward volume acceleration).
To edit an existing inward volume acceleration load using menus or managers, see “Editing step-dependent objects,” Section 3.4.13. To edit the region to which the load is applied, see “Editing the region to which a prescribed condition is applied,” Section 16.8.4.
Click the arrow to the right of the Distribution field, and select the option of your choice from the list that appears:
Select Uniform to define a load that is uniform over the region.
Select an analytical field to define a spatially varying load. Only analytical fields that are valid for this load type are displayed in the selection list. Alternatively, you can click 
to create a new analytical field. (See Chapter 58, “The Analytical Field toolset,” for more information.)
In the Magnitude field, enter the volume acceleration (units L3T–2).
If desired, click the arrow to the right of the Amplitude field, and select the amplitude of your choice from the list that appears. Alternatively, you can click 
to create a new amplitude. (See Chapter 57, “The Amplitude toolset,” for more information.)
Click OK to save your data and to exit the editor.
