Importing 3MF, PLY, STL, and VRML Meshes

) to import a mesh from a , , , or file. When you import a mesh, you can position, rotate, and scale the mesh by using one or several Transform attributes.

	These formats can be imported in 3D models only.

To import additional meshes, add another node. Then COMSOL Multiphysics adds the elements of the newly imported mesh to the existing mesh.

	Meshes from different Import nodes form an assembly. See Conforming, Nonconforming, and Nonmatching Meshes for more information about assembly type meshes.

Meshes on the format 3MF, PLY, STL, and VRML typically contain triangle elements with small angles, large angles, and the mesh elements often vary a lot in size. Such meshes are not well suited for simulations and need to be remeshed or modified before generating a volume mesh.

	For information on remeshing an imported mesh, see Remeshing Imported Meshes and Creating Geometry from Mesh.

	Note that importing a mesh modifies the number of geometric entities. Thus when you are adding this operation to a meshing sequence that is conforming with the component's geometry, a new meshing sequence that is defining its own geometric model is automatically created, and the Import node is added to this new sequence. For more information see The Mesh Node.

Enter the properties for the import using the following sections:

Specify the filename in the field or click the button. You can also click the downward arrow beside the button and choose (

) to open the fullscreen window. Click the downward arrow for the menu (

) to choose (

) to move to the row for this file in the window, (

), and (if you have copied a file location) (

).

Select the check box (selected by default) to automatically form domains for each (connected) finite void region that is defined by the imported surface mesh and analyze these domains with respect to the mesh that may already exist in the sequence.

	Most physics require a mesh on the domains. Use the Free Tetrahedral, Swept, and Boundary Layers operations to fill the domains with domain elements.

When a mesh is imported into COMSOL Multiphysics, the operation automatically determines a partitioning of the mesh into domains, boundaries, edges, and points. If the automatically performed partitioning does not match the requirements, you can modify the face partitioning by manually adjusting the corresponding parameters. For details, see the section Boundary Partitioning Properties.

These settings are available when the list is set to for import of stereolithography files in 3D. Such files contain data for an unstructured triangulated surface.

The check box is selected by default to create a boundary selection of every solid section in the file during import. Typically, there is only one such section. In that case, a selection of the entire boundary is created. This happens also when the STL file is binary and can by definition have no solid sections. The created selections appear in a table in the section that appears below the section. The table has two columns. In the right column, the name of the solid section that the selection has been created from appears. If the section is named or if the file is binary, the name is empty. If the check box is selected and domains was successfully created, a table with selections for the domains appear under the section. The domain selection typically get the same name as the boundary selection for the boundaries that enclose the domain. The selections appear in the same order as the corresponding sections in the file. In the left column, the name of the selection appears. By this name, which can be changed, as well as dimension of the selection, you can find the selection in the model.

The repair tolerance assures that the imported mesh contains no holes and no triangles with sides shorter that the tolerance. From the list, select one of these options:

These sections appear after the has been built. For details, see Entity Selections.