SpaceClaim Online Help

Shared topology in ANSYS

SpaceClaim can share topology (face, edge, and vertex connections) between touching or intersecting bodies and surfaces in designs that are transferred to ANSYS.

Shared topology is the only way to achieve a conformal mesh where bodies meet, and is the only way to be certain that the intersection of bodies is meshed perfectly.

Shared topology also applies to volume and surface bodies that are completely inside of other volume or surface bodies. This situation is common in analyses involving fluid flow.

To create a group of parts that share topology

1. Create a component and set the Share Topology property to Merged or Shared in the properties panel of the component
2. Place any solids, surfaces, beams, or components that you want to share topology into this component.

For ANSYS 15.0 and 16.0, Shared Topology set to Merged applies to the following cases:

• Bodies that are touching each other (same as Shared)
• SurfaceTwo dimensional object that has no thickness (as opposed to a face, which is part of a three-dimensional object). A surface has area but no volume. See Face. bodies that are intersecting each other (same as Shared)
• Volume bodies that are completely inside of other volume bodies. For example SolidObject that encloses volume. A surface becomes a solid if it encloses volume. A is completely inside of SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B which is completely inside of SolidObject that encloses volume. A surface becomes a solid if it encloses volume. C. SolidObject that encloses volume. A surface becomes a solid if it encloses volume. A will share topology with SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B and SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B will share topology with SolidObject that encloses volume. A surface becomes a solid if it encloses volume. C.
• SurfaceTwo dimensional object that has no thickness (as opposed to a face, which is part of a three-dimensional object). A surface has area but no volume. See Face. bodies that are completely inside of volume bodies. For example SurfaceTwo dimensional object that has no thickness (as opposed to a face, which is part of a three-dimensional object). A surface has area but no volume. See Face. A is completely inside of SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B which is completely inside of SolidObject that encloses volume. A surface becomes a solid if it encloses volume. C. SurfaceTwo dimensional object that has no thickness (as opposed to a face, which is part of a three-dimensional object). A surface has area but no volume. See Face. A will share topology with SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B and SolidObject that encloses volume. A surface becomes a solid if it encloses volume. B will share topology with SolidObject that encloses volume. A surface becomes a solid if it encloses volume. C.
• Any combination of the above four cases.
• Not Supported - Cases where volume bodies partially intersect each other or surfaces extending outside of volume bodies.

ANSYS 13.0 through 15.0

• If a component has the Shared Topology property set to Shared (or Merged in ANSYS 15.0 and 16.0), then that component and all components beneath it become a share group.
• The Shared Topology property of components lower in the structure are ignored, so you can't use them to create sharing exceptions.
  • For example, if you set Shared Topology to true for the root component, then the entire model will be one share group.
• The name of the component node is the name of the component from which recursive sharing starts.
• The bodies under this node are listed with full path names through the assembly, such as Axle Sub-Assy (Front)\Wheel (Left)\SolidObject that encloses volume. A surface becomes a solid if it encloses volume., using component names in parentheses if they are present.
• You can have multiple distinct share groups, but a body can only belong to one group.

See the Shared topology tutorial for hands-on experience with shared topology. See ANSYS online help for detailed information about how ANSYS handles multi-body parts and shared topology.

To set shared topology for ANSYS

Put the bodies anywhere under a component that has its Shared Topology property set to Shared (or Merged in ANSYS 15.0 and 16.0), including a sub-assembly (regardless of the sub-assembly's Shared Topology setting).

This property can be found in the properties panel when you select one or more components in the Structure treeDisplay in the Structure panel that shows you each of the objects in your design. You can expand or collapse the nodes of the tree to view the objects. You can rename objects, create, modify, replace, and delete objects, as well as work with components..

The Shared Topology property on Parent componentA component upon which other components depend. For example, in a block with a hole, the block is the parent and the hole is the child. is set to true, so the solids inside the shaded area are shared.

To prevent shared topology in ANSYS

Place solids in a component whose Shared Topology property is set to None, and whose parent components also have this property set to None.

Examples

ANSYS meshes two blocks with shared topology. The blue block will gain a new imprinted face which will be shared between the green and blue blocks. Notice how the nodes of the mesh line up along the bottom of the smaller block.

ANSYS creates separate meshes for two parts because they are in different components and the root part has Shared Topology set to None.

The mesh for shared topology is not the same as merged geometry. Here the boxes are merged, and you can see that the mesh is different than it is for two bodies with shared topology.