Shared Topology Home > CAE Index > ANSYS Index > Release 11.0 Documentation for ANSYS Workbench

Shared Topology occurs when bodies are grouped into multi-body parts. It allows for a continuous mesh across common regions where bodies touch, instead of having to define Contact Regions in Simulation. Consider the example below. The models shown in both pictures are identical. The bodies on the left are two separate bodies, meshed independently. The connection between them must be defined by a contact region in Simulation. The bodies on the right have been grouped into a part in DesignModeler. These bodies share topology in the region where they are in contact, so the mesh is continuous across the part. It is often more desirable for the analysis to have a continuous mesh across the parts than to use contact.

It is important to understand how shared topology works in DesignModeler so you can have better success with multi-body parts. There are several key elements to shared topology.

First, the bodies you see in DesignModeler do not immediately share topology. Each body in the part is treated as its own separate entity with respect to modeling operations. Common regions among the bodies in the part are not combined until the model is transferred out of DesignModeler. Therefore, you will not actually see the shared topology until the model is in Simulation.

Second, the method in which shared topology is created varies depending on the types of bodies that make up your part. There are two methods in which DesignModeler can share topology: Edge Joints and Automatic.

The types of bodies in the multi-body part often dictate how the part will share topology. See the chart below to see how DesignModeler chooses which method to employ.

Table 1  Part Type versus Shared Topology Method

Line Bodies onlyEdge Joints
Line Bodies and Surface BodiesEdge Joints
Surface bodies onlyEdge Joints or Automatic
Solid Bodies onlyAutomatic

In most cases, you cannot choose how the bodies within the part are shared. Also, solid bodies can only be grouped with other solid bodies. A part which contains solid bodies along with bodies of another type is invalid. A part containing only surface bodies is the only type of part in which you may choose the shared topology method. The method being used by the part is displayed in the Shared Topology Method property in the Details View.