Geometry abstraction, polygon geometry, and convergent geometry > Polygon geometry and abstraction

Tools for identifying and repairing polygon body problems

When you create a FEM file, if you select the Associate to Part option in the New FEM dialog box, the software automatically creates polygon geometry from the geometry in your CAD model. As you work with that polygon geometry, you may make unintended modifications to that geometry. In other cases, polygon bodies may develop data consistency or corruption problems.

You can use commands to:

Identify polygon bodies that have inconsistent or corrupt data and repair those inconsistencies.
Recover from unintended modifications to the polygon geometry.

Identifying problematic polygon bodies

You can use the CAE Model Consistency command to check all polygon bodies in your FEM file for issues. If the software identifies problems, it lists the affected polygon bodies by name. As a best practice, you should use the CAE Model Consistency option periodically while you are building your finite element model.

Note:

You must have the CAD part that is associated with the current FEM file loaded before you use this option.

For more information, see Checking CAE model consistency.

Repairing polygon bodies

If the software identifies polygon bodies with consistency issues, and the CAD part that is associated with the current FEM file is loaded, you can use options in the Simulation Navigator to fix them.

When you right-click a polygon body or bodies in the Simulation Navigator, you have three options.

The Recreate and Update option deletes the selected polygon bodies and creates new bodies using the original CAD geometry. The software then updates the polygon geometry so that any mesh mating conditions, meshes, loads, boundary conditions, or CAE geometry recipes are preserved and updated. Use this option when you want to recreate the problematic polygon body and preserve as much of the data that was associated with that body as possible.
The Recreate Only option also deletes the selected polygon body or bodies and creates a new polygon body or bodies using the original CAD geometry. With this option, the software also deletes any mesh mating conditions, modifications made with commands in the Polygon Geometry group and meshes, loads, and boundary conditions associated with the deleted polygon body.The Recreate Only option is an alternative to editing the existing FEM file and changing the Bodies to Use option.
The Delete option removes the selected polygon body from your FEM file. You may want to use the Delete option to exclude a particular body from your analysis.When you delete a polygon body from your model, the software moves that body into a new Excluded Polygon Geometry folder in the Simulation Navigator. Excluded Polygon Geometry Polygon BodyIf you later decide to include that body in your analysis, you right-click the body in the Excluded Polygon Geometry folder and use the Create Polygon Body option to create a new polygon body.

Note:

Although you can use the Delete option to delete polygon bodies that were created by the Face from Mesh command, you cannot use the Recreate and Update or Recreate Only options on those bodies.

When you recreate or recreate and update multiple polygon bodies, the software still processes one polygon body at a time to ensure that there are no errors. After the software recreates all selected polygon bodies, the software updates the Polygon Geometry node in the Simulation Navigator. The software:

Adds the recreated polygon bodies to the end of the list of existing polygon bodies.
Assigns each body a new ID label, beginning with the next highest available ID value.

The following graphic shows a FEM file that contains nine polygon bodies. We selected polygon bodies 1-4 and then selected the Recreate Only command.

The software recreated the bodies and placed them in the Simulation Navigator as shown below. Notice how the new bodies have ID values of 10-13.

Where do I find it?

Application	Pre/Post
Prerequisite	A FEM file as the work part and displayed partThe idealized part loaded
Simulation Navigator	Right-click an existing polygon body and select Recreate and Update, Recreate Only, or Delete

Learn more

Geometry abstraction and polygon geometry

Polygon geometry

Polygon geometry versus lightweight facet bodies

Understanding CAD issues reported during FEM creation

How edges are represented in a solid model

Modeling tolerance values

Comparing geometry idealization and geometry abstraction

Understanding the geometry abstraction process

Displaying suppressed edges in polygon geometry

Checking CAE model consistency

Naming of polygon bodies, meshes, and properties

Synchronizing polygon body names and attributes to the CAD geometry

Controlling polygon body tessellation

Polygon body update process

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