Extrude Geometry

Extrude lines, nodes, surfaces, elements, or facets along their normal direction, a vector, or another line.

  1. From the Topology ribbon, Extrude/Revolve tool group, click the Extrude tool.
    Figure 1.


  2. Optional: On the guide bar, click to define additional options.
    Use the FE tab for additional options related to FE geometry.
  3. Choose between Lines, Nodes, Surfaces, Elements, or Facets using the guide bar selector.
    Note: If Nodes is selected, a line is drawn through the specified nodes before extruding.

    Elements and Facets are enabled if the Mesh checkbox is selected..

  4. Select lines/nodes/surfaces/elements and facets and extrude in the following ways:
    • Use the drop-down in the microdialog to extrude at a fixed normal distance or at a variable distance.
    • Click to define a direction using the Vector tool. Once a direction is defined, manipulate the slider or enter a value in the microdialog.
    • Activate the Guides selector to extrude along selected guiding lines. Use the options in the microdialog to define how the geometry is extruded.
      Fixed Frame
      The geometry is only translated during the extrude, not rotated.
      Line Tangent
      In addition to the translation of the fixed frame option, the geometry is also rotated in the same way that the tangent of the line list rotates.
      Frenet Frame
      In addition to the translation and rotation of the Line Tangent option, the geometry also rotates around the line list tangent axis in the same way as the curvature vector rotates.

      The Frenet Frame option does not work well when the curvature of the line list is not smooth or includes large jumps.

      Reverse Direction
      Defines the extrude in the opposite direction.
  5. Select Mesh to create mesh along with geometry.
    Note:
    • Extruding Elements and Facets creates solid elements without geometry.
    • For surfaces, click to change between Hex and Bounding mesh option.
    • Hex creates solid elements with geometry whereas Bounding creates 2D mesh on the solid surfaces.
  6. On the guide bar, click one of the following:
    • - Apply and stay in the tool
    • - Apply and close the tool
    • - Exit the tool without applying
Note: For the nodes input, based on the geometry creation mode defined, either a CAD surface or an FE geometry surface is created. While using the Extrude tool for lines or surfaces, the input determines whether a CAD surface or an FE geometry surface is created. For example, CAD lines are extruded as CAD surfaces, FE geometry edges are extruded as FE geometry surfaces.

A extrude preview for FE geometry solids is not supported at this time.

Auto-Trim

Use the auto-trim option in the microdialog when extruding nodes and lines.

While extruding lines or nodes, if a continuous surface or mesh is intersected and this option is ON, the newly created surfaces are trimmed at the intersection. The auto-trim option works for both geometry intersecting geometry and mesh. It also works for FE topology intersecting FE topology.

Figure 2. Surfaces Intersecting with Surfaces
Figure 3. Surfaces Intersecting with Mesh
Note: With the auto-trim option ON, if the intersecting mesh or surfaces are not continuous and have gaps as shown in Figure 4, then the resulting surfaces can’t be trimmed completely. However, it will create trim lines as shown in Figure 5. But, since the complete surface is not trimmed, it wont be deleted.
Figure 4.


Figure 5.


When extruding lines, an option is available in the guide bar menu () that allows you to stitch trimmed surfaces to the target surfaces. Note that option is only applicable if auto-trim is turned ON.
Figure 6. Input Lines
Figure 7. Stitch Trimmed Surfaces ON
Figure 8. Stitch Trimmed Surfaces OFF

Hex Meshing

Use the Extrude tool to create a mesh of solid elements.

While the Solid Map tool can automatically create 3D mesh directly on solids as long as the solids you select are already mappable, hex meshing depends on an existing 2D mesh, which is then extrapolated into a 3D mesh based on the parameters you input.

Figure 9.


  • Two opposing faces are called "Source" and "Target" faces.
  • One or more faces that directly connect and enclose the volume between the source and target are called "Guide" faces.
  • The drag direction is the vector from the source face to the destination face.

Create Hex Mesh

  1. From the Topology ribbon, Extrude/Revolve tool group, click the Extrude tool.
    Figure 10.


  2. From the guide bar, select Mesh.
  3. Choose between Surfaces, Elements, or Facets using the guide bar selector.
    Note: Select source geometry that defines the source face of the 3D volume. These can be surfaces, elements, or 2D/3D topological faces.
  4. Optional: On the guide bar, click to define additional options.
    The following advanced options are available:
    Apply orthogonally along extrusion
    Keep the solid elements generated more perpendicular to the surface faces in the along direction.
    Optimize hex elements
    Optimization is performed to improve Jacobian and warpage quality. Avoids negative Jacobian elements.
  5. Create hex mesh in one of the following ways:
    OptionDescription
    Along vector
    1. In the microdialog, set a density value or an element size if not already defined in the options menu.
    2. Enter a thickness value or drag the manipulator to create hex mesh along the element normal.

      The biasing style works in conjunction with biasing intensity. If the intensity is "0", biasing is not applied.

      Figure 11. No Biasing
      Figure 12. Linear
      Figure 13. Bell Curve
      Figure 14. Exponential
      Tip:
      • Click to pick the global X/Y/Z, screen normal, screen parallel, and/or a user-defined direction instead.
      • Click to flip the normal direction.
    Figure 15.


    Figure 16. . 1D elements converted to 2D elements along a vector.
    With Guides/Targets (Optional)
    1. Click the Guides selector.
    2. Select the geometry that defines the face of the 3D volume along which you wish to map the mesh.

      When elements are used, the mapped mesh maintains the nodal positions with selected elements. They can be equivalenced to have common nodes. While selecting nodes, each selection should represent an edge that connects the source and destination.

    3. Click the Target selector.
    4. If desired, select geometry that you wish the 3D mesh to match up with.
      Figure 17.


    5. In the microdialog, set a density value or an element size if not already defined in the options menu.
    Figure 18. . Mesh created with source elements and a midline as a guide.
    Figure 19. . Mesh created with source elements and surfaces/lines as guides.
    Figure 20. . Mesh created with source elements and multiple faces and elements as guides. Topo(2D/3D) element faces are supported.
    Figure 21. . Mesh created with source elements and multiple node paths as guides.