COMSOL 6.4 - Meshing Operations and Attributes

Meshing Operations and Attributes

A meshing sequence consists of Operations and Attributes. Among the operations, there are Generators that generate mesh elements, Modifying Operations that modify existing meshes, and Copying Operations to copy the meshes between components or entities in the same component. The last category of operations can change the number of entities in a mesh either by creating entities, or partition existing entities (Booleans and Partitions, Cleanup and Repair, and Entities).

The Attributes store properties that are used by the operation nodes when creating the mesh. You can also choose the Predefined Mesh Element Sizes to adjust the element size.

The tables below list available mesh operations, attributes, and actions relating to meshes. The tables are roughly organized based on where they appear on The Mesh Toolbar:

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Physics Controlled

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Table 8-2: Import/Export
Icon	Name	Description
	Import	To import a mesh from file, mesh sequence, mesh part, Filter dataset, Partition dataset, or to import a geometry to mesh. See Importing Meshes for more information
	Export	To export a mesh to file. See Exporting Meshes for more information.
	Create Geometry	To import a mesh from file, mesh sequence, mesh part, Filter dataset, or Partition dataset. See Creating Geometry from Mesh for more information.

Table 8-3: Physics Controlled
Icon	Name	Description
	Edit	To edit a physics-controlled sequence. See Editing and Resetting a Physics-Controlled Sequence for more information
	Reset	To reset the sequence to the physics-controlled settings. See Editing and Resetting a Physics-Controlled Sequence for more information.

Table 8-4: Generators
Icon	Name	Description
	Boundary Layers	Create a boundary layer mesh — a mesh with dense element distribution in the normal direction along specific boundaries. This mesh is typically used for fluid flow problems to resolve the thin boundary layers along the no-slip boundaries.
	Edge	Create an edge mesh.
	Free Tetrahedral	Create an unstructured tetrahedral mesh. If no selection is specified, this feature creates a mesh on the remaining domains, boundaries, edges, and points.
	Free Triangular	Create an unstructured triangular mesh on faces in 3D or domains in 2D. For imported meshes, only faces in 3D are supported.
	Free Quad	Create an unstructured quadrilateral mesh on faces in 3D or domains in 2D. For imported meshes, only faces in 3D are supported.
	Mapped	Create a structured quadrilateral mesh on boundaries in 3D and domains in 2D. For imported meshes, only faces in 3D are supported.
	Remesh Domains	Remesh domains in a 2D imported mesh or mesh-based geometry.
	Remesh Edges	Remesh edges in an imported mesh or mesh-based geometry.
	Remesh Faces	Remesh faces in an imported mesh or mesh-based geometry.
	Swept	Create a swept mesh. In domain selection mode this button works in the same way as the Free Tetrahedral button. In boundary selection mode the software creates a swept mesh on the remaining domains using the selected boundaries as source faces.
	Vertex	Create a vertex mesh.

Table 8-5: Attributes
Icon	Name	Description
	Boundary Layer Properties	To specify the location of the boundary layers and the properties, such as the number and thickness of the boundary layers.
	Corner Properties	To specify specific properties for boundary layers in one or more corners.
	Corner Refinement	To specify a refinement in sharp corners. The node considers a vertex in 2D or an edge in 3D to be a sharp corner if the angle between the adjacent selected boundaries, with respect to the selected domain, is greater than a specified angle.
	Distribution	To specify the distribution of mesh elements along an edge or along a sweep.
	Edge Groups	To specify the four groups of edges around a boundary (3D) or domain (2D) that is used to determine the Mapped mesh of the boundary/domain.
	Edge Map	Specify two edges that determine the mapping from source to destination of a copy operation.
	Fixed Mesh	Selecting entities where the mesh is kept fixed when using the Remesh Faces and Remesh Domains operations.
	Identical Mesh	Specify identical mesh on pairs of faces or edges.
	One-Point Map	Specify two points that determine the mapping from source to destination of a copy operation.
	Scale	To scale the element size properties of other attribute nodes.
	Size	To specify the element size.
	Size Expression	To specify the size of mesh elements using an expression evaluated on the grid or on a solution.
	Transform	To specify a position, rotation, or to scale an imported mesh. Supported for the Import operation.
	Two-Point Map	Specify two point pairs that determine the mapping from source to destination of a copy operation.

Table 8-6: Modifying Operations
Icon	Name	Description
	Adapt	Use adaptive mesh generation based on an error estimate from a computed solution.
	Convert	Convert quadrilateral meshes on faces to triangles or hexahedral meshes on domains into tets.
	Reference	Refer to another meshing sequence. Building a Reference node runs the operation nodes of the referenced sequence.
	Refine	Refine a mesh by splitting elements.

Table 8-7: Copying Operations
Icon	Name	Description
	Copy	Copy a mesh from another meshing sequence, typically of imported mesh type, or mesh part into a meshing sequence corresponding to a geometry. Can also be used to copy a mesh within the same meshing sequence.
2D 3D	Copy Domain	Copy a mesh between domains.
2D 3D	Copy Edge	Copy a mesh between edges. A 3D Copy Edge feature can also be used for destination edges of different shapes.
	Copy Face	Make a copy of a face mesh using a rigid body transformation with a scale factor.

Table 8-8: Booleans and Partitions
Icon	Name	Description
	Imprint	To split faces in an imported mesh or mesh-based geometry by imprinting faces, edges, and vertices onto them.
	Intersect with Line	To split mesh elements and geometric entities of a 2D mesh with a straight line.
	Intersect with Plane	To split mesh elements and geometric entities of a 3D mesh with one or several planes.
	Partition with Ball	To split geometric entities in a mesh by an element set defined by a ball.
	Partition with Cylinder	To split geometric entities in a mesh by an element set defined by a cylinder.
	Partition with Box	To split geometric entities in a mesh by an element set defined by a box.
	Partition by Expression	To split geometric entities in a mesh by specifying a logical expression.
	Union	To merge adjacent mesh faces or unite partly overlapping face meshes to form overlap domains.
	Detect Faces	To partition faces of the mesh by searching for shapes that are likely to constitute separate faces.

Table 8-9: Cleanup and Repair
Icon	Name	Description
	Cleanup Wizard	To clean up the geometric model of an imported mesh or mesh-based geometry.
	Fill Holes	To repair an imported 3D surface mesh or mesh-based geometry with minor holes.
	Collapse Entities	To collapse geometrical entities in an imported mesh or mesh-based geometry.
	Merge Entities	To merge geometrical entities in an imported mesh or mesh-based geometry.

Table 8-10: Entities
Icon	Name	Description
	Delete Entities	To delete geometric entities in a mesh or mesh-based geometry.
	Join Entities	To join adjacent geometric entities in an imported mesh or mesh-based geometry.
	Create Domains	To create additional domains within watertight faces in an imported mesh or mesh-based geometry.
	Create Edges	To create meshed edges in an imported mesh or mesh-based geometry.
	Create Faces	To create additional meshed faces within edge loops in an imported mesh or mesh-based geometry.
	Create Vertices	To create vertices in an imported mesh or mesh-based geometry.

Creating named selections in the Mesh sequence is supported for mesh-based geometries and imported meshes. For meshes that operate on geometry, the options are; Creating Named Selections in the Geometry Sequence or Creating Named Selections under Definitions.

Table 8-11: Selections
Icon	Name	Description
	Adjacent Selection	To define a selection of geometric entities that are adjacent to a specified selection. See Adjacent Selection (Mesh Sequences).
	Ball Selection	To define a selection of geometric entities that completely or partly lie inside a ball. See Ball Selection (Mesh Sequences).
	Box Selection	To define a selection of geometric entities that completely or partly lie inside a box. See Box Selection (Mesh Sequences).
	Complement Selection	To define a selection of geometric entities that are not contained in the input entities. See Union Selection, Intersection Selection, Difference Selection, and Complement Selection (Mesh Sequences).
	Cylinder Selection	To define a selection of geometric entities that completely or partly lie inside a cylinder. See Cylinder Selection (Mesh Sequences).
	Difference Selection	To define a selection of geometric entities that are the difference between the selections to add and the selections to subtract. See Union Selection, Intersection Selection, Difference Selection, and Complement Selection (Mesh Sequences).
	Disk Selection	To define a selection of geometric entities that completely or partly lie inside a disk. See Disk Selection (Mesh Sequences).
	Explicit Selection	To define an explicit selection of geometric entities. See Explicit Selection (Mesh Sequences).
	Intersection Selection	To define a selection of geometric entities that are contained in every input selection. See Union Selection, Intersection Selection, Difference Selection, and Complement Selection (Mesh Sequences).
	Union Selection	To define a selection of geometric entities that are the union of two or more selections. See Union Selection, Intersection Selection, Difference Selection, and Complement Selection (Mesh Sequences).
	Selection List	Click to open The Selection List Window. This window lists all geometric entities as well as all available named selections.

Table 8-12: Evaluate
Icon	Name	Description
	Measure	To measure a set of geometric objects or entities selected in the Graphics window. See Geometric Measurements for more information.
	Statistics	To show brief mesh statistics in the Messages window. For a more extensive statistics representation, open Mesh Statistics.
	Plot	To add a mesh plot. For information, see Mesh Plots.

Table 8-13: Clear
Icon	Name	Description
	Clear Built Mesh	To remove the built mesh while keeping the sequence in order to later rebuild the mesh using the same settings. See also Clearing or Deleting a Mesh.
	Clear All Built Meshes	To clear all built meshes in the model while keeping the sequences in order to later rebuild the meshes.
	Clear Built Meshes	To clear all built meshes in the component while keeping the sequences in order to later rebuild the meshes. This action is only available from by right-clicking the Meshes node.
	Clear Sequence	To clear the sequence of all operations and attributes and also clear the built mesh.