HyperMesh and BatchMesher

BatchMesher Mesh Controls

BatchMesher Mesh Controls

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BatchMesher Mesh Controls

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Create model and local mesh controls for BatchMesh meshing in the Mesh Controls tab by right-clicking on the BatchMesher folder and selecting Create from the context menu.

Note:In order to run a meshing job, at least one model mesh control must be defined.

When defining model and local mesh controls, select a parameter mode to determine how criteria and parameters are generated. BatchMesher mesh controls are run using a single CPU.

When generating the mesh, local controls are applied first, starting from the smallest target element size, up to the largest.  The model control is then applied.

hmtoggle_plus1greyNormal

Generates criteria and parameters using an existing set of files.

 

Parameters

Parameter

Description

Criteria File

Specify a criteria file that will be used to automatically generate criteria.

Parameters File

Specify a parameters file that will be used to automatically generate criteria.

Mesh Connectivity

Determines how newly created elements and any adjacent existing elements are connected.

Keep uses existing nodes on any shared boundary edges.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

 

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Generates criteria and parameters on-the-fly by scaling an existing set of files. This parameter mode is useful when you want to evaluate mesh size changes using minimal effort.

 

Parameters

Parameter

Description

Element Size

Element size used when scaling criteria and parameters.

Criteria File

Specify a criteria file that will be used to automatically generate criteria.

The "min size" and "max size" thresholds are created by simple proportional scaling of the base thresholds to the requested element size. All other criteria is not changed.

Parameters File

Specify a parameters file that will be used to automatically generate criteria.

All dimensionless parameters and options are not changed.

All parameters having a length dimension are proportionally scaled using the scale factor target size/original size.

Element size
Max thin solid thickness (for midsurface extraction)
Surface holes table: radii ranges and washers widths, target radii if given directly ( not as a radius fraction )
Solid holes table: radii ranges
Surface fillet table:  radii and widths ranges, maximal chordal deviation
Flanges recognition:  max and min flanges width, maximal width for narrow surface width allowed to be deleted
Duplicated surfaces search tolerance – scaled if   0.5   < scale_factor <  2
Edges equivalencing tolerance – scaled if   0.5   < scale_factor <  2
Narrow fillets merging width threshold
Beads to be removed maximal height
Flanged holes to be removed maximal height
edge fillets defilleting -  max radius
logos to be removed : maximal height and depth
threads to be removed max depth
trias reduction maximal and minimal elements size
elements warpage fix – maximal offset normally to surfaces

Mesh Connectivity

Determines how newly created elements and any adjacent existing elements are connected.

Keep uses existing nodes on any shared boundary edges.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

 

hmtoggle_plus1greyAuto Generate

Generates criteria and parameters on-the-fly using very basic and limited input parameters. This parameter mode is useful for basic and simple use cases, where existing parameter and criteria files do not exist and you do not have strict mesh requirements.

 

Criteria

The following mesh control input parameters are automatically populated within specific Criteria file fields. The Min Size - Good/Warn/Worst and Max Size - Good/Warn/Worst are internally calculated. All other Criteria file settings are hard-coded.

Mesh Control Input Parameter

Criteria File Field

Element Size

Target element size

Min Size - Ideal

Max Size - Ideal

Minimum Element Size

Min Size - Fail

Maximum Element Size

Max Size - Fail

 

Parameters

The following mesh control input parameters are automatically populated within specific Parameter file fields. All other parameters and behaviors are kept as default.

Mesh Control Field

Parameters File Field

Element Size

Target element size

Element Type

Create mesh with element type, with “align” and “size” checkboxes enabled.

Element Order

Element order

Element Feature Angle

Feature angle during element cleanup

Geometry Cleanup

Enables or disables, in its entirety, the Geometry cleanup section

 

When Geometry Cleanup is enabled, two threshold radii are defined as:

min_rad = max(0.4*Element Size, 0.8*Minimum Element Size)
mid_rad = max(0.6*Element Size, min_rad)
max_rad = 3.0*Element Size

 

Enabling the Geometry Cleanup parameters listed below, facilitates the following behaviors.

Remove Small Holes removes small surface and solid holes with a radii range of 0 – min_rad.
Create Washers creates one layer of washers with a minimum of 6 elements and an auto-defined width for surface holes in the min_rad – max_rad range.
Seed Holes enables hole seeding for surface and solid holes, per the rules below. If Create Washers is enabled, this is ignored for surface holes.
omin_rad – mid_rad = 4 elements minimum
omid_rad – max_rad = 6 elements minimum
Allow Movement Across Edges enables major post-mesh element cleanup operations to improve the final element quality at the expense of edge capturing and performance.
Advanced Feature Capture enables improved feature capturing at the expense of element quality and performance.

 

In the Parameters file, the following parameters are automatically defined. All other parameters are kept as default.

Extract midsurfaces is enabled with the Method set to skin offset.
Geometry Cleanup
oSurface fillet recognition
The following thresholds are defined:
min_rad = 0.7*max(0.4*Element Size, Minimum Element Size)
min_wid = 0.49*Pi*min_rad
mid_rad = 1.307*max(0.5*Element Size, Minimum Element Size)
mid_wid = 0.5*Pi*mid_rad
max_rad = 1.5*Element Size
max_wid = 0.51*Pi*max_rad
The following number of elements rows are enforced:
min_rad – mid_rad and min_wid – mid_wid = 1 element across
mid_rad – max_rad and mid_wid – max_wid = 2 elements across
oFlange recognition is enabled with:
Elements across flange width = 2
Maximum width of flange = 3.5*Element Size
Minimum width of flange = max(0.5*Element Size, Minimum Element Size)
Delete flange narrow surfaces with width < = auto
oOther options
Suppress beads with height < = min( 0.2*Element Size, Minimum Element Size)
Suppress flanged holes with height < = min(0.15*Element Size, Minimum Element Size)
Remove edge fillets with radius < =  0.9*Element Size
Remove logo with size < =  3.0*Element Size, and height < =  min(0.15*Element Size, Minimum Element Size)
Element cleanup
oApply tria reduction with min elem size > = 0.5*Element Size and max size < 1.5*Element Size
oMove across free edges, max dist < = 0.0025 * element size