Mesh Elements for 1D, 2D, and 3D Geometries


	Mesh Element Numbering Conventions in the COMSOL Multiphysics Programming Reference Manual.

1D Geometries

The mesh generator discretizes the domains (intervals) into smaller intervals (or mesh elements). The endpoints of the mesh elements are called mesh vertices.

The boundaries (or vertices) defined in the geometry are represented in the mesh by boundary elements (or vertex elements).

2D Geometries

The mesh generator discretizes the domains into triangular or quadrilateral mesh elements. If the boundary is curved, these elements represent an approximation of the original geometry. The sides of the triangles and quadrilaterals are called mesh edges, and their corners are mesh vertices. A mesh edge must not contain mesh vertices in its interior.

The boundaries defined in the geometry are discretized (approximately) into mesh edges, referred to as boundary elements (or edge elements), which must conform with the mesh elements of the adjacent domains.

The geometry vertices are represented by vertex elements.

3D Geometries

The mesh generator discretizes the domains into tetrahedral, hexahedral, prism, or pyramid mesh elements whose faces, edges, and corners are called mesh faces, mesh edges, and mesh vertices, respectively.


	For 3D meshing, platforms handle floating-point operations differently, which sometimes results in slight differences between identical model files that are generated on two different computers.

The boundaries in the geometry are discretized into triangular or quadrilateral boundary elements. The geometry edges are discretized into edge elements.

Pyramid Elements

Pyramid elements appear in the mesh in these situations. If you:

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Import a NASTRAN® file containing pyramid elements.

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Create a Swept mesh where the source and destination faces share an edge and the source face contains a triangular mesh.

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Convert a quad mesh to a triangular mesh for a face adjacent to a domain that contains a mesh.

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If you create a Free Tetrahedral mesh in a domain that is adjacent to a face with quadrilateral elements.

Create a Boundary Layers mesh in 3D for a geometry with sharp edges.


	The Hermite and divergence types of finite elements do not work with pyramids.