To Define a Topology Region

1. Click Home > Topology Region. The Topology Region dialog box opens.

2. In the Name box, type a name for the topology region.

3. To change the color used for a topology region, click , and select a color in the Color Editor dialog box.

4. To define the percentage of material with which to start the optimization, in the Init. mass fraction box, enter a value from 0–1. At the first design cycle, each element in the topology region is assigned a density value that is the same as this value.

5. To set the method of defining the topology region, in the References box, select an option:

◦ Component—Select parts.

◦ Volume—Select one or more volume regions, click the References collector, and then select geometrical references. Press and hold CTRL to select multiple items.

6. To select regions to exclude from the topology optimization, next to Excluded regions, click the Volumes collector, and select geometric references to exclude. Press and hold CTRL to select multiple items.

7. To select a coordinate system from which fabrication constraints is enforced, select an option:

◦ World—Default Cartesian coordinate system of the model.

◦ Selected—Click the collector, and then select a user-defined coordinate system.

8. To add fabrication constraints, in the Constraint 1, Constraint 2, and Constraint 3 boxes, select a constraint from the list. You can add up to 3 constraints for a topology region.

9. To specify whether to set a minimum thickness value for the material that is kept when the part is optimized:

◦ To not set a minimum thickness value, in the Min. size control box, select No.

◦ To enable setting a minimum thickness value, in the Min. size control box, select Yes. Then you can define the following items:

▪ Min. member size—Enter the minimum thickness value for the resultant optimized geometry.

▪ To smooth the results, type a value from 0–1 in the Spread fraction box. A value of 0.0 means no smoothing.

▪ To specify whether to set a value for the maximum dimension of any resultant topology component:

▪ To not set a maximum thickness value, in the Max. size control, select No.

▪ To enable setting a value for the maximum dimension of any resultant topology component, in the Max. size control box, select Yes. Then you can define the following items:

▪ Max member size (SYMV3)—Enter a value for the maximum dimension of any resultant topology component.

It is recommended that the Max member size should be three times the Min. member size.

▪ Min. gap (SYMV4)—Enter a distance value to specify the minimum distance between the items you generate with topology optimization.

10. Enter values to use in the Power Rule that creates relationships between the design variables and the materials:

◦ Enter a value for real value 1 Real value 1 (RV1). This value is usually between 2.0 and 3.0.

◦ To define a scale factor for the minimum allowable Young’s modulus, enter a value for real value 2 Real value 2 (RV2). This value is usually between 0.0 and 1.0, with a default of 10-6.