Creating Bounding Bodies

In 3D-CAD, you can simplify a complex geometry by replacing detailed bodies with bounding bodies. For example, on a circuit board you can create bounding bodies to replace detailed parts such as the capacitors, resistors or other components.

This feature supports all four types of input bodies: facet solid bodies, non-faceted solid bodies, facet sheet bodies, and non-faceted sheet bodies. All newly created bodies are non-faceted solid bodies. The bounding bodies feature succeeds in creating bounding bodies in all cases except for the following:
  • The Create one Bounding Body per Body option is activated and one or more of the selected input bodies is a planar sheet body.
  • The Create one Bounding Body per Body option is deactivated, each of the selected input bodies is a planar sheet body, and all of the selected input bodies are coplanar.
The bounding bodies feature will partially succeed only when all of the following conditions are satisfied.
  • The Create one Bounding Body per Body option is enabled.
  • At least two input bodies are selected.
  • A bounding body can be created for at least one of the selected input bodies.
  • A bounding body cannot be created for at least one of the selected input bodies.

To create a bounding body:

  1. Select one or more bodies and use one of the following methods:
    • In the graphics window, right-click one of the bodies and select Create Bounding Bodies.
    • Select one or more bodies or body groups in the 3D-CAD simulation tree, right-click and select (Create Bounding Bodies).
    • In the Features toolbar, click (Body Feature) and select (Create Bounding Bodies).
    The Bounding Bodies panel appears on the left of the graphics window.
  2. In the Edit dialog, set Bounding Body Shape to either Block or Cylinder.
    The Block shape forms boxes around the input bodies, whereas the Cylinder shape encloses the input bodies as shown below:

You can specify the alignment direction of the bounding body. For bounding cylinders, the alignment direction defines the direction of each cylinder axis. For bounding blocks, the alignment direction defines the direction of one of the block's sets of four parallel edges. To specify the alignment direction:
  1. Set Direction Type to one of the following options:
    • Automatic—Simcenter STAR-CCM+ automatically computes the alignment direction.
    • Specified—allows you to specify the alignment direction as a vector with respect to a reference coordinate system or imported coordinate system. You can import a Cartesian, cylindrical, or spherical coordinate system. To specify the vector:
      1. Set Coordinate System Source to either Reference Coordinate System or Imported, and specify the coordinate system.
      2. Set Direction Vector to the alignment direction of the bounding body.
    • Reference Axis—allows you to specify the alignment direction using an axis, either from the 3D-CAD scene or feature tree.
  2. If you want to generate one bounding body per body, then activate Create one Bounding Body per Body.
    When Create one Bounding Body per Body is checked, the feature creates one bounding body for each of the selected input bodies, as shown in the image below.

    When Create one Bounding Body per Body is unchecked, the feature creates a single body which bounds all of the selected input bodies, as shown in the image below.

  3. If you want to retain the selected bodies after the operation, then activate Keep Selected Bodies.
    The behavior of this option depends on whether or not the Create one Bounding Body per Body is activated, as explained below:
    • When Keep Selected Bodies is activated:
      • If Create one Bounding Body per Body is activated, 3D-CAD creates an additional body for each selected input body. The name of each new body is derived from the name of its corresponding selected input body.
      • If Create one Bounding Body per Body is deactivated, 3D-CAD creates a single additional body with a generic name.
      • The Create Body Group check-box becomes available. When activated, 3D-CAD creates a new body group containing all the selected input bodies and the bounding bodies.
    • When Keep Selected Bodies is deactivated:
      • If Create one Bounding Body per Body is activated, 3D-CAD replaces the geometry of each selected input body with a bounding body.
      • If Create one Bounding Body per Body is deactivated, 3D-CAD deletes the selected input bodies and create a single new body with a generic name.
  4. Click OK.