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Model and Local

Model and Local

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Model and Local

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Model and local mesh controls define the meshing mode, element size, element type, and additional parameters used to create a mesh of shell elements using surface geometry or existing shell elements.

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 mesh mode to use during automatic meshing to determine the type of meshing to perform. For more information on the different mesh modes, refer to Mesh Modes. The mesh mode for model controls can be changed at any time. However, for local controls, the mesh mode is defined only at the time of creation.

hmtoggle_plus1greySize and Bias

Generates mesh using elements of a uniform size that you specify.

 

Parameters


Parameter

Description

Use Model Settings

Sets all of the main parameters from the model control.

For local controls only.

Element Size

Average element size. The length of any active (shared or free) surface edge divided by the element size determines the number of elements to place along that edge.

Element Type

Type of elements used to create mesh during automatic meshing.

For more information, see Mesh Types.

Element Order

First order creates elements using a linear shape function; Second order creates elements using a polynomial shape function.

For local controls, this is inherited from the model control and cannot be set independently.

 

Parameter

Description

Organization

Destination Component

Original stores newly created elements in the component to which the surface belongs; Current stores newly created elements in the "current" active component.

Valid only for model controls.

Mesh Connectivity

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

Keep uses existing nodes on any shared boundary edges.
Redo re-seeds existing nodes along the boundary of the newly created mesh to optimize mesh quality.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

Valid only for model controls.

Flow

Align

Produces a more orthogonal quad-dominant mesh.

Only available when the Element Type is set to Mixed.

flow_align1

Here, there is no flow alignment

flow_align2

Flow alignment is used, producing straighter rows of elements

Size

Enforces the global mesh element size with minimal min/max element size variations.

Only available when Element Type is set to Mixed and Flow: Align is enabled.

Mapping

Size

Keeps elements roughly the same size.

Skew

Prevents mesh from producing highly-skewed elements.

Other - Surface Based Automeshing Only

Link Opposite Edges

Links mesh settings on opposing edges of rectangular surfaces. Changes applied to one linked edge will be applied to the other. By default, the maximum aspect ratio (AR) to allow between large and small edge sizes of linked edges is 2.11.

Manually specify an aspect ratio by setting Aspect Ratio Less Than to User Specified. Increasing the value adds more surfaces to the linked chain, whereas decreasing the value removes some surfaces from the linked chain.

density_link_edges_before

Mesh without link opposite edges selected.

density_link_edges_after

Mesh with link opposite edges selected and Aspect Ratio Less Than set to Auto.

arequal8

Mesh with link opposite edges selected and Aspect Ratio Less Than set to User Specified, with an Aspect Ratio of 8.0.

 

Parameter

Description

Auto Features

Defines logical faces when using existing finite elements as a basis for automeshing.

Connected detects features based on the specified feature angle, and makes additional effort to void any "orphan" or non-closed feature lines. It works similarly to Auto Detect, but includes a more rigorous check to combine small areas and avoid creating features that end abruptly or do not connect to any other features.

automesh_not_connected

Before re-meshing

automesh_connected_features

After re-meshing with connected features selected

Auto Detect detects features based on the specified feature angle.
Surface Edges automatically detects and utilizes geometric lines associated with selected elements as features in the re-meshing operation.

automesh_not_connected

Before re-meshing

automesh_surface_edges

After re-meshing with surface edges selected

None ignores extra features defined by any of the above methods.

User Features

A selection of user-created 1D elements which define features that need to be captured along with any feature angle-based features. Only 1D elements should be selected here, as any other element selections are ignored.

Anchor Nodes

Nodes that will remain and be re-used in the new mesh. Anchor nodes are "fixed" so that the automesher cannot move or replace them; in essence, they are exceptions to the re-meshing operation, and the new mesh must utilize them.

 

 

hmtoggle_plus1greyQI Optimize

An iterative automatic mesh generation method driven by element quality criteria.

 

Parameters


Parameter

Description

Use Model Settings

Sets all of the main parameters from the model control.

For local controls only.

Element Size

Average element size. The length of any active (shared or free) surface edge divided by the element size determines the number of elements to place along that edge.

Element Type

Type of elements used to create mesh during automatic meshing.

For more information, see Mesh Types.

Element Order

First order creates elements using a linear shape function; Second order creates elements using a polynomial shape function.

For local controls, this is inherited from the model control and cannot be set independently.

Criteria File

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

 

Parameter

Description

Organization

Destination Component

Original stores newly created elements in the component to which the surface belongs; Current stores newly created elements in the "current" active component.

Valid only for model controls.

Mesh Connectivity

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

Keep uses existing nodes on any shared boundary edges.
Redo re-seeds existing nodes along the boundary of the newly created mesh to optimize mesh quality.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

Valid only for model controls.

Flow

Align

Produces a more orthogonal quad-dominant mesh.

Only available when the Element Type is set to Mixed.

flow_align1

Here, there is no flow alignment

flow_align2

Flow alignment is used, producing straighter rows of elements

Size

Enforces the global mesh element size with minimal min/max element size variations.

Only available when Element Type is set to Mixed and Flow: Align is enabled.

Mapping

Size

Keeps elements roughly the same size.

Skew

Prevents mesh from producing highly-skewed elements.

Other - Surface Based Automeshing Only

Smooth Across Common Edges

Node smoothing moves nodes across adjacent surface edges whose feature angle is less than the value specified. When selected, strict adherence to the geometry of the surface edges in not enforced for non-feature edges; some deviation from the geometry can occur.

 

Parameter

Description

Auto Features

Defines logical faces when using existing finite elements as a basis for automeshing.

Connected detects features based on the specified feature angle, and makes additional effort to void any "orphan" or non-closed feature lines. It works similarly to Auto Detect, but includes a more rigorous check to combine small areas and avoid creating features that end abruptly or do not connect to any other features.

automesh_not_connected

Before re-meshing

automesh_connected_features

After re-meshing with connected features selected

Auto Detect detects features based on the specified feature angle.
Surface Edges automatically detects and utilizes geometric lines associated with selected elements as features in the re-meshing operation.

automesh_not_connected

Before re-meshing

automesh_surface_edges

After re-meshing with surface edges selected

None ignores extra features defined by any of the above methods.

User Features

A selection of user-created 1D elements which define features that need to be captured along with any feature angle-based features. Only 1D elements should be selected here, as any other element selections are ignored.

Anchor Nodes

Nodes that will remain and be re-used in the new mesh. Anchor nodes are "fixed" so that the automesher cannot move or replace them; in essence, they are exceptions to the re-meshing operation, and the new mesh must utilize them.

 

 

hmtoggle_plus1greyEdge Deviation

Determines how far the mesh elements can deviate from the actual edges of the surfaces meshed, or when in the case of re-meshing elements, deviation from inferred edges based on features.

 

Parameters


Parameter

Description

Use Model Settings

Sets all of the main parameters from the model control.

For local controls only.

Minimum Size

Minimum allowable element size.

Maximum Size

Maximum allowable element size.

Maximum Deviation

Allowable deviation between the element edge and the surface edge. To meet this requirement, element edge lengths along a curved surface edge are reduced as needed down to a lower limit set by the minimum element size.

 

Maximum Feature Angle

Maximum angle across which elements can be maintained. When two adjacent elements’ normals exceed this angle, a new set of nodes is created between them to maintain clean feature lines. Using higher value results in elements spanning the feature line.

automesh_mesh_featureangle30

With an appropriate value, the features lines are preserved.

automesh_mesh_featureangle60

If the feature angle is too high, the feature lines are blurred.

Element Type

Type of elements used to create mesh during automatic meshing.

For more information, see Mesh Types.

Element Order

First order creates elements using a linear shape function; Second order creates elements using a polynomial shape function.

For local controls, this is inherited from the model control and cannot be set independently.

 

Parameter

Description

Organization

Destination Component

Original stores newly created elements in the component to which the surface belongs; Current stores newly created elements in the "current" active component.

Valid only for model controls.

Mesh Connectivity

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

Keep uses existing nodes on any shared boundary edges.
Redo re-seeds existing nodes along the boundary of the newly created mesh to optimize mesh quality.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

Valid only for model controls.

Flow

Align

Produces a more orthogonal quad-dominant mesh.

Only available when the Element Type is set to Mixed.

flow_align1

Here, there is no flow alignment

flow_align2

Flow alignment is used, producing straighter rows of elements

Mapping

Size

Keeps elements roughly the same size.

Skew

Prevents mesh from producing highly-skewed elements.

Other - Surface Based Automeshing Only

Link Opposite Edges

Links mesh settings on opposing edges of rectangular surfaces. Changes applied to one linked edge will be applied to the other. By default, the maximum aspect ratio (AR) to allow between large and small edge sizes of linked edges is 2.11.

Manually specify an aspect ratio by setting Aspect Ratio Less Than to User Specified. Increasing the value adds more surfaces to the linked chain, whereas decreasing the value removes some surfaces from the linked chain.

density_link_edges_before

Mesh without link opposite edges selected.

density_link_edges_after

Mesh with link opposite edges selected and Aspect Ratio Less Than set to Auto.

arequal8

Mesh with link opposite edges selected and Aspect Ratio Less Than set to User Specified, with an Aspect Ratio of 8.0.

 

Parameter

Description

Auto Features

Defines logical faces when using existing finite elements as a basis for automeshing.

Connected detects features based on the specified feature angle, and makes additional effort to void any "orphan" or non-closed feature lines. It works similarly to Auto Detect, but includes a more rigorous check to combine small areas and avoid creating features that end abruptly or do not connect to any other features.

automesh_not_connected

Before re-meshing

automesh_connected_features

After re-meshing with connected features selected

Auto Detect detects features based on the specified feature angle.
Surface Edges automatically detects and utilizes geometric lines associated with selected elements as features in the re-meshing operation.

automesh_not_connected

Before re-meshing

automesh_surface_edges

After re-meshing with surface edges selected

None ignores extra features defined by any of the above methods.

User Features

A selection of user-created 1D elements which define features that need to be captured along with any feature angle-based features. Only 1D elements should be selected here, as any other element selections are ignored.

Anchor Nodes

Nodes that will remain and be re-used in the new mesh. Anchor nodes are "fixed" so that the automesher cannot move or replace them; in essence, they are exceptions to the re-meshing operation, and the new mesh must utilize them.

 

 

hmtoggle_plus1greySurface Deviation

Generates mesh within the limits of element deviation from input elements.

 

Parameters


Parameter

Description

Use Model Settings

Sets all of the main parameters from the model control.

For local controls only.

Minimum Size

Minimum allowable element size.

When there are model and local mesh controls for surface deviation, and the minimum size of neighboring mesh controls are different, the minimum size will automatically propagate from the smaller mesh size to neighboring surfaces.

Maximum Size

Maximum allowable element size.

Growth Rate

Determines how rapidly elements can increase in size as they are created further and further away from features.

automesh_growthrate

Elements further from the features grow larger with each row.

Span Angle

Controls the element size at curve input. The smaller the angle, the more refined curvature will be and the more preserved the input shape will be. By default span angle is 25.0 degrees.

In the green circle below, β is the span angle of the edge ab. The length of ab is less than 2R( sin β/2 ).

span_angle

Valid only for element-based controls.

Feature Angle

Determines which features to preserve. The mesher identifies features internally and preserves/refine them based on the defined feature angle.

Valid only for element-based controls.

Element Order

First order creates elements using a linear shape function; Second order creates elements using a polynomial shape function.

For local controls, this is inherited from the model control and cannot be set independently.

 

Parameter

Description

Organization

Mesh Connectivity

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

Keep uses existing nodes on any shared boundary edges.
Redo re-seeds existing nodes along the boundary of the newly created mesh to optimize mesh quality.
Break ignores existing adjacent elements and generates mesh according to the element size and type you specified.

Valid only for model controls.

 

Parameter

Description

Auto Features

Defines logical faces when using existing finite elements as a basis for automeshing.

Connected detects features based on the specified feature angle, and makes additional effort to void any "orphan" or non-closed feature lines. It works similarly to Auto Detect, but includes a more rigorous check to combine small areas and avoid creating features that end abruptly or do not connect to any other features.

automesh_not_connected

Before re-meshing

automesh_connected_features

After re-meshing with connected features selected

Auto Detect detects features based on the specified feature angle.
Surface Edges automatically detects and utilizes geometric lines associated with selected elements as features in the re-meshing operation.

automesh_not_connected

Before re-meshing

automesh_surface_edges

After re-meshing with surface edges selected

None ignores extra features defined by any of the above methods.

User Features

A selection of user-created 1D elements which define features that need to be captured along with any feature angle-based features. Only 1D elements should be selected here, as any other element selections are ignored.

Refine Features

Apart from capturing the features if refine feature is turned enabled, you can define the mesh size to be applied to features selected/found by any of the above methods.

 

 

hmtoggle_plus1greyRigid Body Mesh

Generates mesh to represent the topology of a rigid object. Available only for surface-based meshing.

 

Parameters


Parameter

Description

Use Model Settings

Sets all of the main parameters from the model control.

For local controls only.

Minimum Size

Minimum allowable element size.

Maximum Size

Maximum allowable element size.

Maximum Deviation

Allowable deviation between the element edge and the surface edge. To meet this requirement, element edge lengths along a curved surface edge are reduced as needed down to a lower limit set by the minimum element size.

 

Maximum Feature Angle

Maximum angle across which elements can be maintained. When two adjacent elements’ normals exceed this angle, a new set of nodes is created between them to maintain clean feature lines. Using higher value results in elements spanning the feature line.

automesh_mesh_featureangle30

With an appropriate value, the features lines are preserved.

automesh_mesh_featureangle60

If the feature angle is too high, the feature lines are blurred.

Element Type

Type of elements used to create mesh during automatic meshing.

For more information, see Mesh Types.

Element Order

First order creates elements using a linear shape function; Second order creates elements using a polynomial shape function.

For local controls, this is inherited from the model control and cannot be set independently.

 

Parameter

Description

Organization

Destination Component

Original stores newly created elements in the component to which the surface belongs; Current stores newly created elements in the "current" active component.

Valid only for model controls.