Creating a Submodel FEM

You can use the submodel method in the Automated FEM app to create a submodel for a selected portion of a larger model.

You can use an interactive tool in the 3D area to manipulate a box or sphere shape that defines the cutting surface. You use this surface to isolate the region of the model that forms the submodel. After defining the submodel area, you choose the mesh procedure used for each part within the submodel. You can also choose procedures for creating connections if your submodel contains them.

This task shows you how to:

Before you begin:
  • A product must be open in Model Assembly Design.
  • To use surface (triangle or quad) mesh procedures, you need to define publications containing the meshed areas. These publications must point to the 2D or 3D geometry, not the containing PartBody. Publications are optional for other predefined procedures. However, if you do not use publications, the main PartBody must contain the part geometry required to generate a mesh.
See Also
About Automated FEM Methods
Correcting Finite Element Model Problems

Define the Submodel Region

  1. From the Automated FEM section of the action bar, click Automated FEM , and then select Submodel.
  2. In the Automated FEM: Advanced dialog box, click Submodel Selection.
    The context toolbar appears.
  3. From the context toolbar, select Cutting box or Cutting sphere for the shape of the cutting surface.
  4. Define the initial placement and size of the cutting surface.
    1. From the context toolbar, click Initialize shape .
    2. In the 3D area, click start and end points to locate the shape.
  5. In the 3D area, use the handles and the robot to refine the location of the cutting surface.

    Tip: From the context toolbar, use the Hide robot and Show robot commands to hide or show the robot.

  6. Optional: From the context toolbar, click Advanced editing to open a dialog box in which you can enter exact values for the origin and size of the shape.

  7. Click OK to confirm the selection area and to exit the selection procedure.
    The cutting shape is shown on the model, and the Automated FEM dialog box displays.
  8. Continue with the next step Define the Meshing Procedure.

Define the Meshing Procedure

Before you begin: Define the Submodel Region.
  1. From the Mesh and Properties options, select one of the following automated modeling mesh procedures:
    OptionDescription
    Submodel Quad Creates a surface mesh of quadrilateral elements.
    Submodel Triangle Creates a 2D mesh of triangular elements.
    Submodel Tetrahedron Creates a 3D mesh of tetrahedron elements.
  2. From the Applied on options, select one of the following to define the search domain:
    OptionDescription
    All Parts Includes all parts fully contained in or intersected by the cutting tool.
    Parts with Publication Includes all parts that contain publications.
    Parts With Name Includes parts defined by the user's input.

    For parts, the input can be the part name or the path to the part. For geometry, you must specify the path to the product.

    For product paths, separate each object in the path with "!". If you do not define a product path, the app searches all the parts and products.

    For geometric paths, prefix "|" to the geometric set, and separate each subsequent object in the geometric path with "!". The first object must be a geometric set. If the first object is not defined, the app searches the geometric features in all geometric sets.

    Examples:

    • Product1!Product2!Part3
    • Product1!Part2|GeomSet1!GeomFeat2
    • |GeomSet1!GeomFeat2
    • |!GeomFeat2
  3. From the Selection Mode options, specify the bodies to mesh within the submodel:
    OptionDescription
    Main body Creates the FEM for the primary 3D geometry in each 3D shape (the part body, a solid body, or one volume in an ordered geometric set).
    All geometries Creates the FEM for all 3D geometry in the assembly, including part bodies, bodies, and ordered geometric sets.
    Visible geometries Creates the FEM for visible geometry only.
  4. From the list of available publications, select the Support.

    The support corresponds to the list of available publications in the assembly. You must select a publication for surface quad and triangle mesh procedures. Support selection is optional for tetrahedron mesh procedures.

  5. Specify the mesh parameters.
  6. Optional: Click to add additional mesh procedures.
  7. Continue to the next step Define Connection Options.

Define Connection Options

Before you begin: Define the Meshing Procedure.
  1. From the Connections options, specify the automated modeling procedure that you want to use and the parts to which the procedure applies:
    OptionDescription
    Read from design Imports connections contained in the product structure.
    Geometrical point detection Creates connections based on point detection rules.
    Geometrical line detection Creates connections based on line detection rules.
    Virtual bolt detection Creates connections on virtual bolts.
  2. From the Applied on options, select one of the following to define the search domain:
    OptionDescription
    All Parts Includes all parts.
    Geometries with Publication Includes all geometries that containing publications.
    Parts Or Geometries With Name Includes parts and geometries defined by the user's input.

    For parts, the input can be the part name or the path to the part. For geometry, you must specify the path to the product.

    For product paths, separate each object in the path with "!". If you do not define a product path, the app searches all the parts and products.

    For geometric paths, prefix "|" to the geometric set, and separate each subsequent object in the geometric path with "!". The first object must be a geometric set. If the first object is not defined, the app searches the geometric features in all geometric sets.

    Examples:

    • Product1!Product2!Part3
    • Product1!Part2|GeomSet1!GeomFeat2
    • |GeomSet1!GeomFeat2
    • |!GeomFeat2
    Meshed Supports Includes all meshed geometries.
  3. Click Select rule to select a connection template.

    New connections use the connection properties defined in the template.

  4. If you are using one of the detection methods, enter the search tolerances.

    The detection algorithm finds connection locations that are within the defined search tolerances.

  5. Optional: Enter a Prefix, which is applied to the fastener names.

    The prefix is prepended to the fastener names.

    Prefixes can help organize or identify groups of imported fasteners.

  6. From the Creation location options, select how the model connections are stored in engineering connections:
    OptionDescription
    One engineering connection for all connection properties Creates a single engineering connection for all detected connection properties.
    One engineering connection per connected parts Creates or selects engineering connections based on which parts are connected.
    One engineering connection per connection property Creates an engineering connection for each different connection property.
    In current finite element model Creates connection definitions in the current finite element model for any detected connections.
  7. Optional: Click to add additional connection procedures.
  8. Optional: Select Create one FEM per part to create separate finite element models for each part.
  9. Optional: If you are reading fasteners from the design, select Create Automated Specification to save the detection tool options so that you can easily regenerate the connections after a model change. For more information, see Structural Model Creation: About Automated Specifications.

    This option is available only if you do both of the following:

    • Set the Search domain option to Meshed supports.
    • Set the engineering connection Creation location to In current finite element model.
    Note: If you selected the Read from design procedure, the Search domain restriction is not relevant.