Parameter Settings
Overview of the geometry cleanup and defeaturing parameter settings used to define things such as washer layers around holes, defeaturing pinholes and solid holes, rows of elements along fillets, and many other options.
- Access
- Select from the menu bar.
Basic
Basic parameters include importing, outputting, and meshing.
Import Options
- Import model with tolerance
- Tolerance value to be used while importing the CAD model.
Output Options
- Extract midsurfaces
- Select the Extract midsurfaces checkbox to
extract the midsurface before meshing using the selected extraction
method. Only the midsurface geometry is meshed and the original geometry
is deleted. Note: Selecting this option activates the Midsurface settings.
- Allow midmesh
- Select the Allow midmesh checkbox to create a
direct midmesh for the parts where midsurface extraction is difficult or
not possible, such as plastics, castings and machined
parts.Note: Selecting this option activates the Midmesh settings.
- Geometry cleanup
- Select the Geometry cleanup checkbox to enable
additional cleanup parameters that can be turned on and off
independently.Note: Selecting this option activates the Geometry Cleanup settings.
- Create mesh
- Selecting this option activates the Quality Correction tab on the left.
Mesh Options
- Target element size
- Desired element size for meshing and optimization.Note: The element size defined here should match the ideal value for min length and max length as defined in the criteria file. If this does not match, BatchMesher may not be able to produce meshes that adhere to the target quality requirements.
- Element type
- Type of elements to create.
- Element order
- Create first or second order elements.
- Element organization
- Organize new elements in either the current component or the original surface's component(s).
Midsurface
Midsurface parameters define the tasks that are performed by BatchMesher when extracting the midsurface.
- Method
- Select method to use when extracting the midsurface before meshing.
- Sheet metal only
- Only consider geometry for midsurface extraction that meets the user
defined settings for the options specific to sheet metal.Note: If this option is disabled, it will result in a time savings, but all parts will be attempted to have a midsurface extracted.
- Maximum thin solid thickness to width ratio
- Maximum ratio between the approximate thickness of the thin solid part (shortest dimension) and its approximate width (2nd shortest dimension). This parameter is used to limit the midsurface extraction to parts for which the thickness is clearly smaller than the length and width.
- Maximum thin solid thickness
- Ignore thin solids with a thickness less than the specified value during midsurface extraction.
- Minimum feature angle between the solid’s edge and its faces
- Minimum angle used to distinguish top and bottom faces of a thin solid from its sides. Angles less than the specified value will be treated as if they were flat for purposes of midsurface extraction.
- Pre-midsurface geometry cleanup
- Perform geometry cleanup steps on the model before midsurface extraction.
Midmesh
Midmesh parameters define settings used to create the midmesh.
- Extract element size
- The element size used while creating (extracting) midmesh.
- Ignore flat edges
- Do not imprint flat edges from the input geometry onto the midmesh.
- Flatten connections
- Align/flatten the midmesh at ribs/connections.
- Step offset mode
- This option allows finer control of how stepped geometry (one side continuous surface, and opposite side steps) is captured. This option is valid only when flatten connections is enabled. Values can be:
- Defeature openings with width <
- Remove small holes and openings less than the specified width.
- Suppress proximity edges factor
- Remove 1D topology edges within the given factor of the minimum size from the criteria file.
- Combine non-manifold edges factor
- Join non-manifold edges within the given factor of the minimum size from the criteria file.
- Defeature ribs width factor
- The minimum size factor for removing small ribs. Ribs closer than this factor times minimum size will be suppressed. Default is 0.9.
Geometry Cleanup
Geometry Cleanup parameters define a variety of geometry feature recognition and preparation tasks performed by BatchMesher.
- Flat feature suppression level, a curvature based feature suppression.
- Suppress edges by proximity, allows to handle feature edges in close proximity, generally based on minimum element size.
Controlling the above parameters can result in good feature capture with minimum quality index failures. However, features are given more importance which might increase the failed element count based on geometry and the cleanup parameter values. It is important to define all of the settings appropriately.
Edges
- Equivalence tolerance
- Tolerance to use for equivalencing (stitching) edges, in conjunction
with the options below.
- Auto
- Calculate the tolerance internally.
- <value>
- Enter a tolerance. This is more useful when the auto tolerance is not sufficient to make all of the necessary connections.
- Allow T-connections
- Allow T-connections (non-manifold edges) to be created during the stitching process.
- Within components only
- Allow stitching only within components. Stitching between edges of different components is not allowed.
Surfaces
- Delete duplicates
- Define which duplicate surfaces to delete before meshing.
- All
- Consider all of the surfaces in all of the components against each other.
- Within components only
- Consider all surfaces within components only. Duplicate surfaces between components are not found.
- None
- Do not remove duplicate surfaces.
- Tolerance
- Define the tolerance used when finding duplicates.
- All
- Automatically calculate the tolerance from the model size and other relevant geometric parameters.
- <value>
- Enter a tolerance. This is more useful when the auto tolerance is not sufficient to find all of the duplicates.
- Fix overlaps with tangency angle <
- Fix overlapping surfaces.
- Auto
- Calculate the tangency angle internally.
- <value>
- Enter a maximal tangency angle to fix overlapped surfaces.
Component boundaries and feature edges
- Preserve component boundaries
- Do not suppress or remove components' boundary edges during geometry cleanup, and do not move elements nodes across the components' boundaries. In some cases, maintaining boundaries for adjacent components that do not have any structural meaning would significantly worsen the element quality results.
- Suppress edges by proximity <
- Suppress full or partial feature edges within the defined proximity value.
- Suppress sharp steps <
- This option allows geometry cleanup to consider sharp steps if they are
failing the defined minimum element size. You can enter an absolute
value for proximity or you can use the minimum element size, or a
factor.
Note: Suppress edges by proximity does not allow you to suppress sharp steps in proximity unless this option is explicitly defined.
- Flat feature suppression level
- Suppresses feature edges based on curvature break angle. For the ease of use, you can select a curvature break angle range, which varies from very low to very high.
- Feature character size
- The curvature break angle is calculated based on this setting.
- Custom feature angle
- Custom feature angle helps adjusts user-defined suppression
level.Note: Available when Flat feature suppression level is set to user defined.
Beads/Bosses
Geometry that represents beads on sheet metal parts is recognized.
- Suppress beads: Heights <
- Enable bead recognition and suppress any beads with a height less than the specified value. This helps eliminate small elements and aids in creating a good mesh flow.
- Preserve rounded bead midline
- If ON, the geometry trim at the peak will be created, suppressing other
top feature lines and capturing bead with nodes at the peak.
Note: If bead has geometry trim line at the top close to medial position, that line could be used. If multiple trim lines are present, based on the proximity, one of the trim lines could be kept capturing peak of the bead.
Fillets
Recognize surface fillets and edge fillets.
- Remove edge fillets with radius <
- Square off any fillets/rounded edges located on free edges and having radii below the specified value. This helps to create a good mesh pattern in such areas. For concave fillets, this means material is removed. For convex fillets, this means material is added.
- Surface fillet recognition
- Recognize surface fillets in order to perform one or more of the
following options:
- Prevent the main (long) edges of the fillets from being suppressed, and also prevent the nodes of those edges from moving while fixing element quality.
- Remove/defeature fillets. Gaps may result if complicated fillets cannot be removed.
- Split the fillets along the mid-line and suppress the edges.
- Specify the number of elements across the width of the fillets for given fillet radii. The width value is defined as the arc length of the fillet.
- Specify the chordal deviation to be achieved while meshing.
- Minimize transitions
- Allows mesh settings to be defined as an exact number of rows when the checkbox is disabled.
Flanges
Geometry that represents flanges on sheet metal parts is recognized.
- Flange recognition
- Flanges may be modified to suppress construction lines, subdivide them into rectangular areas, or otherwise prepare them for proper meshing. As this functionality is not supported for solid geometries, it should be disabled for such models to improve performance.
- Elements across flange width
- Minimum number of elements to be created across the flange width.
- Maximum width of flange
- Maximum flange width to consider for flange recognition.
- Minimum width of flange
- Minimum flange width to consider for flange recognition.
- Delete flange narrow surfaces with width <
- Controls the removal of narrow flange surfaces to avoid creation of
sliver elements and disruptions in the mesh flow.
- Auto
- Delete narrow flange surfaces when the maximal narrow surface width is the minimum of 0.2*element_size and min_element_size.
- <value>
- Delete narrow flange surfaces when the maximal narrow surface width is the minimum of the specified value.
Holes 2D
Surface 2D holes are recognized and treated appropriately.
2D hole recognition
- 2D hole recognition
-
- Add circumferential trim lines for washer
- Keep geometry trim lines for washers
- Suppress flanged holes with height <
- Recognize holes with small downward flanges and eliminate those flanges with a height less than the specified value. Flanges with a height less than the minimal element size are extended to the minimal element size if not removed.
- Circular hole recognition table data
- Define radii ranges and additional options in the table.
- Attempt to maintain narrow slot as
- Rectangular ends – the slot ends are meshed to have rectangular
ends.
Rounded ends – the slot ends are meshed using the pattern
indicated in the following image.
Note: If this option is turned off, slot ends are meshed per the parameters defined in the hole table.
- Add circumferential trim lines for washer
- Keep geometry trim lines for washers.
- Suppress flanged holes with height <
- Recognize holes with small downward flanges and eliminate those flanges with a height less than the specified value. Flanges with a height less than the minimal element size are extended to the minimal element size if not removed.
- Use file for circular hole recognition
- Specify additional files containing X, Y, Z center locations of all of the holes to consider.
Slots Recognition Table Data
Define slot sizes and additional options in the table.
Column | Action | ||||
---|---|---|---|---|---|
Size 1, Size 2 | The size 1 and size 2 are defined as shown in the following image: | ||||
Range 1, Range 2 | Based on Size 1 and Size 2 entries, the ranges are auto filled so the sizes in between are considered properly. | ||||
Treatment | The manner in which you handle the following options:
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# Elems | Enter the minimum (for example, > 6) /exact (for example 8) number of elements to create around the circular ends of the slots as shown below, or set to auto to automatically select the number of elements so that the min and max element size requirements are satisfied, with the best possible representation of the hole shape. | ||||
Washer Type | For seed, slots can have Rounded or Rectangular ends as shown below:
Note: If the option is “auto”, slot ends are meshed per the
parameters defined in the hole table.
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1st Washer/2nd Washer/3rd Washer | Sets the width of the first, second, third washer as a constant value (select the blank entry in the drop down and enter a value), a scale of the hole radius, for example 0.6*radius, a subtraction formula, for example 14.0-radius, or an automatic determination based on element quality. |
Rectangular/Square Hole Recognition Table Data
Define rectangular hole sizes and additional options in the table.
Column | Action | ||||
---|---|---|---|---|---|
Size 1, Size 2 | The size 1 and size 2 are defined as shown in the following image: | ||||
Range 1, Range 2 | Based on Size 1 and Size 2 entries, the ranges are auto filled so the sizes in between are considered properly. | ||||
Treatment | The manner in which you handle the following options:
|
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# Elems | Enter the minimum (for example, > 6) /exact (for example 8)
number of elements to create around the circular ends of the
slots as shown below, or set to auto to automatically select the
number of elements so that the min and max element size
requirements are satisfied, with the best possible
representation of the hole shape. Note: Auto is not recommended
for holes with washer layers.
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Washer Type | Radial or Corner quad washer types are supported.
|
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1st Washer/2nd Washer/3rd Washer | Sets the width of the first, second, third washer as a constant value (select the blank entry in the drop down and enter a value), a scale of the hole radius, for example 0.6*radius, a subtraction formula, for example 14.0-radius, or an automatic determination based on element quality. |
Elliptical Hole Recognition Table Data
Define ellipical hole sizes and additional options in the table.
Column | Action |
---|---|
Size 1, Size 2 | The size 1 and size 2 are defined as shown in the following image: |
Range 1, Range 2 | Based on Size 1 and Size 2 entries, the ranges are auto filled so the sizes in between are considered properly. |
Treatment | The manner in which you handle the following options:
|
# Elems | Enter the minimum (for example, > 6) /exact (for example 8) number of elements to create around the circular ends of the slots as shown below, or set to auto to automatically select the number of elements so that the min and max element size requirements are satisfied, with the best possible representation of the hole shape. |
Washer Type | Radial washer types are supported. |
1st Washer/2nd Washer/3rd Washer | Sets the width of the first, second, third washer as a
constant value (select the blank entry in the drop down and
enter a value), a scale of the hole radius, for example
0.6*radius, a subtraction formula, for example 14.0-radius, or
an automatic determination based on element quality. Note: If
Auto for width is defined, in some cases washers will not be
built if its not possible to have good washer
elements.
|
Mixed Hole Recognition Table Data
Define mixed hole sizes and additional options in the table. Various shapes can be combined and the equivalent diameter can be specified based on which the shapes will be identified and treated.
If circle, slot and rectangle is selected, then various washer treatment options are available. Currently other shapes are not supported.
For parameter files before version 2021.1 within circular holes table, slots were treated as well. Now that slots can be defined separately, the legacy files once loaded in the new version slots table is automatically filled based on the circular holes data. You have the flexibility to use this data or completely delete and add new data. The new data is populated based on following rule: If holes of certain radius are removed in the holes table, corresponding slots with same radius will be removed as long as slot length is shorter than 1.4 x target element size and width less than 95% minimum element size.
Holes 3D
Surface 2D holes are recognized and treated appropriately.
- 3D hole recognition
- Surface holes of different sizes are recognized and treated appropriately. A table becomes enabled to define the radii ranges and additional options.
- 3D hole recognition table data
- Define radii ranges and additional options in the table. Add/remove element rows by clicking (Add Row) and (Remove Row).
Logos
Use the Logo Recognition parameters to remove small geometric features that represent logos in the model design.
- Remove logos
- Recognize and remove small geometric features that represent logos.
- Size <
- Maximum size of a letter in the logo, as measured along/parallel to the "shiny" surface.
- Height <
- Maximum height/depth of a letter in the logo, as measured normal to the "shiny" surface.
- Concavity factor
- Creates a filter that provides more flexible control of automatic logo
recognition. As this is a heuristic tool, it may remove real features,
such as flat bottom round dimples, that were not intended for removal.
The Concavity factor is a quantitative measure of a letters shape
complexity, formally defined as:The contour_accumulated_turn_angle is the
sum of angles between a letters contour straight parts. Curved parts of
a contour letter are approximated by a segmented line composed of short
straight segments. For completely concave contour, such as circles,
quads, and hexagons, concavity factor contour_accumulated_turn_angle =
360 degrees and concavity factor = 0.Tip: Extend the recognition and removal of a logo by reducing the Concavity factor.
Threads
Geometry that represents threads is recognized.
- Remove threads
- Recognizes and removes threads.
- Depth <
- Remove cylindrical or conical threads with a depth less than the specified value, and replaces them with a smooth cylinder or cone surface.
- Replace removed threads with cylinder diameter
- Method used to define the diameter of the replacing cylinder or cone.
- autodecide
- Automatically determine diameter based on the diameter of a blank before thread cutting begins.
- major
- Use diameter of the thread major.
- mean
- Use diameter of the thread mean.
- minor
- Use diameter of the thread minor.
Quality Correction Parameter
Used by BatchMesher to generate a mesh on the cleaned-up geometry.
BatchMesher has a powerful mesh flow algorithm which considers the shape of the geometry and aligns the mesh to create orthogonal meshes automatically. It also helps to reduce number of trias and places them strategically to avoid bad mesh patterns. BatchMesher is able to control the average element size in order to generate a more uniform mesh.
These parameters control the behavior of the post-mesh element cleanup operations. They are intended to fix elements failing the quality criteria, to reduce number of tria elements for mixed/quad meshes, to correct bad mesh patterns, and to fix mesh flow for fillets. All of the element cleanup operations are compliant with the quality criteria, in that they should improve or at least not worsen the mesh quality.
All element cleanup behaviors are based either on nodal movement (smoothing), changing element connectivity (collapsing, splitting, and so on) or local remeshing.
Node movement
- Move across shared edges <=
- Define the maximum distance to move nodes across shared edges to correct the quality.
- Move across free edges <=
- Define the maximum distance to move nodes outside of free edges to correct the quality.
- Move across non-manifold edges <=
- Move nodes away from the geometry's non-manifold edges by less than the specified distance. Applies only to Rebuild Mesh.
- Offset from surfaces <=
- Move nodes off the geometry to correct warped elements.
- Keep on edges for free round holes with <=
- Do not allow any nodes to move off the edges of free holes (without
washers) with less than a specified number of elements. This is useful
if distortion of the holes is not allowed.
- Allow to move on plateau feature top edges
- Plateau feature top edge nodes are allowed to move to fix the failed
elements.
Correct warped elements
- Divide quads into trias
- Split quads into trias to meet the element criteria defined in the criteria file.
Element cleanup settings
- Feature angle
- Element feature angle to maintain while performing element cleanup.
- Folding angle
- Elements whose angle exceeds this value are considered folded over, and BatchMesher attempts to clean them up.
Special Components
The Special component selection parameters define a method for selecting special components.
- Special component selection
- Enable special component selection.
- Selected components treatment
- Provides options for meshing.
- Mesh without geometry cleanup
- Mesh the listed components but will not perform any geometry cleanup on them before meshing. Any remaining components that are not listed will be batch meshed using the normal process, including geometry cleanup.
- Mesh and keep connectivity
- Mesh the listed components while maintaining connectivity to any existing mesh.
- Ignore and keep connectivity
- Ignore the listed components while maintaining connectivity to any existing mesh. The mesh and geometry of the ignored components are not touched during batch meshing. The mesh created on other adjacent components is connected to any existing mesh on the ignored components.
- Selected components
- A table becomes enabled to specify special components. Add/remove components by clicking (Add Row) and (Remove Row). In the Name field, enter component name.