Creating a rotational symmetry restriction

You can specify a rotational symmetry geometric restriction for a topology or sizing optimization.

Related Topics
Creating a geometric restriction in a topology or sizing optimization
Creating a geometric restriction in a shape optimization

Context:

A rotational symmetry geometric restriction forces the optimized model to be symmetric about a specified axis, as shown in Figure 1:

Figure 1. Rotational symmetry from a topology optimization.

You specify the axis of symmetry by selecting the axis of a coordinate system. You can use the global coordinate system, or you can create a datum coordinate system (see Methods for creating a datum coordinate system, for more information). In addition, you must enter an angle that specifies the size of the repeating segment. You can choose to remove frozen regions from the symmetry restriction.

  1. From the main menu bar, select Geometric RestrictionCreate.

    The Create Geometric Restriction dialog box appears.

    Tip: You can initiate the Create procedure in two other ways:

    • Click Create in the Geometric Restriction Manager. (You can display the Geometric Restriction Manager by selecting Geometric RestrictionManager from the main menu bar.)

    • Click the tool in the Optimization module toolbox.

  2. From the Create Geometric Restriction dialog box that appears, enter the name of the geometric restriction.

  3. Select Rotational symmetry or Rotational symmetry (Sizing) from the list of geometric restrictions, and click Continue.

  4. From the viewport, select the region in which the rotational symmetry will be enforced or click Done to apply the rotational symmetry restriction to the entire model.

    By default, Abaqus/CAE allows you to select all of the model. To select faces or cells, use the Selection toolbar to change the type of object that you can select to Face or Cells. For more information, see Filtering your selection based on the type of object.

    If you would rather select from a list of existing sets, do the following:

    1. Click Sets on the right side of the prompt area.

      Abaqus/CAE displays the Region Selection dialog box containing a list of available sets.

    2. Select the set of interest, and click Continue.

    Note:

    The default selection method is based on the selection method you most recently employed. To revert to the other method, click Select in Viewport or Sets on the right side of the prompt area.

  5. When you have finished selecting the geometric restriction region, click Done in the prompt area. For more information on selecting objects, see Selecting objects within the viewport.”

    The Edit Geometric Restriction dialog box appears.

  6. Select the coordinate system, and select the axis of the coordinate system that represents the axis of symmetry.

  7. Enter the Repeating segment size, which is the angle (in degrees) specifying the size of the repeating segment. The value must be greater than or equal to 2°.

  8. If desired, toggle on Ignore frozen area to remove any frozen regions from the symmetry restriction.

  9. Click OK to create the rotational symmetry geometric restriction and to exit the editor.