Analysis Connections

Analysis connections are used to specify the associations or interactions between regions of bodies in an assembled product. After you have defined the geometric positioning constraints of the assembly at the Product level in the Assembly Design workbench, you can use analysis connections to specify the physical nature of the connections in the Nonlinear Structural Analysis workbench. The following sections discuss the connection properties available in Nonlinear Structural Analysis and Thermal Analysis:

Creating General Analysis Connections: Creates a connection between two parts when a suitable contact or coincidence positioning constraint from the Assembly Design workbench does not already exist. The association can be between two vertices or between one or more edges or faces.

Creating Point Analysis Connections: Creates a connection between two parts and a group of points.

Creating Point Analysis Connections Within One Part: Creates a connection between a part and a group of points.

Creating Line Analysis Connections: Creates a connection between two parts and a line.

Creating Line Analysis Connections Within One Part: Creates a connection between a part and a line.

Creating Surface Analysis Connections: Creates a connection between two parts and a surface.

Creating Surface Analysis Connections Within One Part: Creates a connection between a part and a surface.

Creating Points to Points Analysis Connections: Creates a connection between two vertices or between two groups of points.

Creating Point Analysis Interfaces: Creates a connection between a mesh part and a vertex or a group of points.

Creating General Analysis Connections

General analysis connections are used as supports for connection properties. In general, you use a general analysis connection to specify an association between two parts when a contact or coincidence assembly constraint is not appropriate. General analysis connections created in Nonlinear Structural Analysis and Thermal Analysis are used by the following connection properties:

Contact pair

You use a general analysis connection and a contact pair to define contact (including self-contact) between selected surfaces. You also use a general analysis connection and a contact pair to define contact involving shells and beams.

Fastened pair

You use a general analysis connection and a fastened pair to link two part bodies that are tied together at their common boundary and behave as if they were a single body.

Pressure fitting connection property

You use a general analysis connection and a pressure fitting connection property to link two part bodies that are assembled in a press-fit configuration.

Rigid connection property

You must use a general analysis connection and a rigid connection property to link two part bodies that are connected by a rigid rod and behave as if they were a single body. The general analysis connection can connect a point, edge, or face to a point, edge, or face.

Smooth connection property

You must use a general analysis connection and a smooth connection property to link two part bodies that are connected by a common boundary and behave as if their interface is soft. The general analysis connection can connect a point, edge, or face to a point, edge, or face.

Spring connection property

You must use a general analysis connection to define the points that support a spring connection property. You can use only general analysis connections that join one point to another point—connections that include a face or an edge are not allowed.

You can select the same vertex for both points when you are creating a general analysis connection that defines the two points. When you select the general analysis connection as the support for a spring connection property, Nonlinear Structural Analysis assumes that the spring connects the vertex to ground.

Bolt tightening/Virtual bolt tightening connection property

You use a general analysis connection and a bolt tightening (or virtual bolt tightening) connection property to define the contact surface pairing between the bolt thread and the bolt support tapping.

When you use a general analysis connection to define contact, the first component that you select is used as the master surface in the contact pair; the second component that you select is used as the slave surface. If one of the components must act as the master surface in a contact pair (for example, an analytical rigid surface), select this component first when creating the general analysis connection.

You can define self-contact between faces by selecting the same faces for both the first and second components of the general analysis connection. Self-contact is typically the result of large deformation in a model. It is often difficult to predict which regions will be involved in the contact or how they will move relative to each other. You can select a general analysis connection that allows for self-contact as support for a contact pair.

This task shows you how to create a general analysis connection between two parts in the assembly.

  1. Click the General Analysis Connection icon .

    The General Analysis Connection dialog box appears, and a General Analysis Connection object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the general analysis connection by editing the Name field.

  3. Select the first component of the connection. You can select a single vertex or one or more edges or surfaces. However, the type of entity that you select depends on the connection property that the general analysis connection will support. For example, you must select points when the general analysis connection will be used to support a spring connection property.

    Note:  You can select a group from the mesh part as a component of a general analysis connection. See Creating Groups for more information.

  4. Select the second component of the connection. You can select a single vertex or one or more edges or surfaces. If the second component is the same as the first component, the solver assumes that the edge or surface is interacting with itself in self-contact.

  5. Click OK in the General Analysis Connection dialog box.

    A symbol representing the general analysis connection appears between the first and second component.

Creating Point Analysis Connections

Point analysis connections are used for projecting points onto parallel faces of separate parts in the assembly. You can use a point analysis connection as support for a spot welding connection property.

This task shows you how to create a point analysis connection between two parts in the assembly.

  1. Click the Point Analysis Connection icon .

    The Point Analysis Connection dialog box appears, and a Point Analysis Connection object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the point analysis connection by editing the Name field.

  3. Select the first part.

  4. Select the second part.

  5. Select the points that will be used as the welding points.

  6. Click OK in the Point Analysis Connection dialog box.

    A symbol representing the point analysis connection appears between the two parts.

Creating Point Analysis Connections Within One Part

Point analysis connections within one part are similar to point analysis connections. However, point analysis connections within one part are used for projecting points onto parallel faces of the same part in the assembly. You can use a point analysis connection within one part as support for a spot welding connection property.

This task shows you how to create a point analysis connection within a single part in the assembly.

  1. Click the Point Analysis Connection Within One Part icon .

    The Point Analysis Connection Within One Part dialog box appears, and a Point Analysis Connection Within One Part object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the point analysis connection within one part by editing the Name field.

  3. Select the part.

  4. Select the points that will be used as the welding points.

  5. Click OK in the Point Analysis Connection Within One Part dialog box.

Creating Line Analysis Connections

Line analysis connections are used for projecting a line onto parallel faces of separate parts in the assembly. You can use a line analysis connection as support for a seam welding connection property.

This task shows you how to create a line analysis connection between two parts in the assembly.

  1. Click the Line Analysis Connection icon .

    The Line Analysis Connection dialog box appears, and a Line Analysis Connection object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the line analysis connection by editing the Name field.

  3. Select the first part.

  4. Select the second part.

  5. Select the line that will be used as the welding line. You can select only a single line.

  6. Click OK in the Line Analysis Connection dialog box.

    A symbol representing the line analysis connection appears between the two parts.

Creating Line Analysis Connections Within One Part

Line analysis connections within one part are similar to line analysis connections. However, line analysis connections within one part are used for projecting a welding line onto parallel faces of the same part in the assembly. You can use a line analysis connection within one part as support for a seam welding connection property.

This task shows you how to create a line analysis connection within a single part in the assembly.

  1. Click the Line Analysis Connection Within One Part icon .

    The Line Analysis Connection Within One Part dialog box appears, and a Line Analysis Connection Within One Part object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the line analysis connection within one part by editing the Name field.

  3. Select the part.

  4. Select the line that will be used as the welding line. You can select only a single line.

  5. Click OK in the Line Analysis Connection Within One Part dialog box.

Creating Surface Analysis Connections

Surface analysis connections are used for projecting a welding surface onto parallel faces of separate parts in the assembly. You can use a surface analysis connection as support for a surface welding connection property.

This task shows you how to create a surface analysis connection between two parts in the assembly.

  1. Click the Surface Analysis Connection icon .

    The Surface Analysis Connection dialog box appears, and a Surface Analysis Connection object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the surface analysis connection by editing the Name field.

  3. Select the first part.

  4. Select the second part.

  5. Select the face that will be used as the welding surface. You can select only a single face.

  6. Click OK in the Surface Analysis Connection dialog box.

    A symbol representing the surface analysis connection appears between the two parts.

Creating Surface Analysis Connections Within One Part

Surface analysis connections within one part are similar to surface analysis connections. However, surface analysis connections within one part are used for projecting a welding surface onto parallel faces of the same part in the assembly. You can use a surface analysis connection within one part as support for a surface welding connection property.

This task shows you how to create a surface analysis connection within a single part in the assembly.

  1. Click the Surface Analysis Connection Within One Part icon .

    The Surface Analysis Connection Within One Part dialog box appears, and a Surface Analysis Connection Within One Part object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the surface analysis connection within one part by editing the Name field.

  3. Select the part.

  4. Select the face that will be used as the welding surface. You can select only a single face.

  5. Click OK in the Surface Analysis Connection Within One Part dialog box.

Creating Points to Points Analysis Connections

Points to points analysis connections are similar to general analysis connections; however, points to points analysis connections are used for connecting a mesh part with a second mesh part. The connection is made through a group of one or more points or vertices. You should use the Move Mesh Nodes tool in the Advanced Meshing Tools workbench or the Add Constraints tool in the Advanced Surface Mesher workbench to associate nodes on the meshed part with geometric points.

You apply a nodes to nodes connection property to a points to points analysis connection and specify the degrees of freedom between the selected components.

This task shows you how to create a points to points analysis connection between two mesh parts.

  1. Click the Points to Points Analysis Connection icon .

    The Points to Points Analysis Connection dialog box appears, and a Points to Points Analysis Connection object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the general analysis connection by editing the Name field.

  3. Select the first component of the connection. You can select a single vertex, a single point, or a group of points or vertices.

  4. Select the mesh part to associate with the first component.

  5. Select the second component of the connection. You can select a single vertex, a single point, or a group of points or vertices.

  6. Select the mesh part to associate with the second component.

  7. Click OK in the Points to Points Analysis Connection dialog box.

Creating Point Analysis Interfaces

Point analysis interfaces are used for connecting a mesh part to a group of one or more points or vertices. You apply a node interface property to a point analysis interface and specify the translational and rotational stiffness of the connection.

This task shows you how to create a points analysis interface.

  1. Click the Point Analysis Interface icon .

    The Point Analysis Interface dialog box appears, and a Point Analysis Interface object appears in the specification tree under the Analysis Connections objects set.

  2. You can change the identifier of the points analysis interface by editing the Name field.

  3. Select the first component of the connection. You can select a single vertex, a single point, or a group of points or vertices.

  4. Select the mesh part to associate with the component.

  5. Click OK in the Point Analysis Interface dialog box.

    A symbol representing the point analysis interface appears between the first component and the mesh part.