Pipe Idealization is a (boundary) condition used to model pipes that have cross-section distortion. This is common for curved pipe structures under loading. It is related to the mesh and acts much like a mesh control. Pipe elements are created by meshing lines or curves.
Prerequisites
In the Line Body’s (Geometry Object) Details pane Definition category, the Model Type option must be set to .
The scoped line-body must be meshed with higher order elements. This means that the Element Order option under the Defaults group of the Mesh Object must be set to . If not, the solver reports an error.
Extend Elbow Elements
You can extend the elbow elements to adjacent edges within the same body in order to reduce the boundary effects caused by the incompatible section deformation between edges modeled as straight pipes and high deformation pipes (elbows). If you do not want to extend the elements, under the Extend to Adjacent Elements section of the Details panel set Extend to No. To extend the elements, set Extend to . You can then enter a value, which will extend the elements to the adjacent edge up to a length of factor times selected pipe diameter. If the length calculated by factor times pipe diameter is less than the length of one element, it will still be extended by one element.
Support Limitations
Note the following limitations for this condition.
If one or more of the elbow elements has a subtended angle of more than 45 degrees, a warning is reported. The solution can proceed, or you may want to use a finer mesh for better results.
Pipe Idealization cannot be used with symmetry.
Although the solution will account for cross section distortions, the graphics rendering for the results will display the cross sections in their original shape.
Given elbow elements (ELBOW290) with inner pipe temperature specifications only, the application will, by default, specify this inner temperature as outer temperature as well.
This page includes the following sections:
| Analysis Types |
| Dimensional Types |
| Geometry Types |
| Topology Selection Options |
| Applying a Pipe Idealization Boundary Condition |
| Details Pane Properties |
| Mechanical APDL References and Notes |
Analysis Types
Pipe Idealization is available for the following analysis types:
Dimensional Types
The supported dimensional types for the Pipe Idealization boundary condition include:
3D Simulation: Supported for Line Bodies only. Apply to one or more edges or at least two vertices.
Geometry Types
The supported geometry types for the Pipe Idealization boundary condition include:
Wire Body/Line Body/Beam:
Topology Selection Options
The supported topology selection options for Pipe Idealization include:
Edge. It can only be scoped to edges that have been modeled as pipes. It can be scoped directly to the geometry or to a Named Selection containing edges that are modeled as pipes.
Nodes: Supported for node-based Named Selections.
Applying a Pipe Idealization Boundary Condition
To apply a Pipe Idealization:
On the Environment Context tab, click Conditions>Pipe Idealization. Alternatively, right-click the Environment tree object or in the Geometry window and select Insert>Pipe Idealization.
Verify that in the Details panel for the Mesh object, Element Order in the Defaults group is set to .
If you choose to Extend to Adjacent Elements, enter a Factor.
Define the Scoping Method.
Details Pane Properties
The selections available in the Details pane are described below.
| Category | Property/Options/Description |
|---|---|
| Scope |
Scoping Method - Options include:
|
| Definition |
Suppressed - Include ( - default) or exclude () the boundary condition. Formulation - Read-only field defined as . |
| Extend to Adjacent Elements |
Extend - Do not extend to adjacent elements () or specify as (default). Factor |
Mechanical APDL References and Notes
The following Mechanical APDL commands, element types, and considerations are applicable for this boundary condition.