Inertia can be defined for a part in the Property module or for an assembly in the Interaction module. You can specify the following types:

• Point mass/inertia. You can define lumped mass and rotary inertia at a point on a part or on an assembly. You can also define mass and inertia proportional damping. In an Abaqus/Standard analysis, you can define composite damping. For more information, see “Point masses,” Section 30.1.1 of the Abaqus Analysis User's Guide, and “Rotary inertia,” Section 30.2.1 of the Abaqus Analysis User's Guide.

• Nonstructural mass. You can define nonstructural mass for a region on a part or on an assembly. For more information, see “Nonstructural mass definition,” Section 2.7.1 of the Abaqus Analysis User's Guide.

• Heat capacitance. You can define concentrated heat capacitance at a point on a part or on an assembly. For more information, see “Point capacitance,” Section 30.4.1 of the Abaqus Analysis User's Guide.

Select SpecialInertiaCreate: type from the main menu bar in the Property module or the Interaction module to define inertia. Select Edit from the same menu to make changes to an existing definition.

Inertia definitions appear in the Model Tree in the Engineering Features container under the part (if created in the Property module) or under the assembly (if created in the Interaction module).

When you define inertia, you can select objects from the viewport to identify the region on which to apply the inertia. By default, a set or surface is created that contains the selected objects. You can change this behavior by toggling off the option to create a set or surface in the prompt area. A default name is provided in the prompt area, but you can enter a new name.

When you apply inertia to regions of the model, you can choose to display symbols in the viewport that indicate where you have applied the inertia. If you apply inertia to geometry, symbols appear at the vertices. If you apply inertia to an orphan mesh, symbols appear at the nodes. For information about graphical symbol types, see “Symbols used to represent special engineering features,” Section C.3. For information about controlling the visibility of these symbols, see “Controlling the display of attributes,” Section 76.15.

For detailed instructions on creating this type of engineering feature, see the following sections:

• “Defining point mass and rotary inertia,” Section 33.3

• “Defining nonstructural mass,” Section 33.4

• “Defining heat capacitance,” Section 33.5