Intersect with Plane

) to intersect the elements of an imported mesh with one or several parallel planes. The selected geometric entities are partitioned by the planes. A selection of domains will also lead to a partitioning of adjacent boundaries and edges. Closed regions formed by the edges in the intersection plane will be filled with meshed faces by default (see Intersections for more information).

	This operation is available for 3D models only.

To intersect an imported mesh with planes:

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For an imported mesh, right-click in the window to open up The Graphics Context Menu and select (

) from the menu.

Define the geometric entities to intersect. From the : Choose , , or to specify the domains, boundaries or edges to partition with the plane. Only unmeshed domains are supported. The option selects all boundaries and edges.

	The intersection of meshed domains is not supported. It is possible to build the operation as long as the specified planes do not intersect any meshed domain. To remove a domain mesh while keeping the boundary mesh, add a Delete Entities operation, add the domains to delete, and clear the Delete adjacent lower-dimensional entities check box. To later restore the domains and domain mesh, add a Create Domains operation and lastly a Free Tetrahedral operation.

The layout of the section depends on the selection in the list, where you select how to define the plane. Choose one of the following types:

In the list, select one of the global coordinate planes xy, yz, zx, yx, zy, or xz, denoting the first and second axes of the plane’s local coordinate system. Specify an offset using one of the following settings in the list:

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(the default) to define the distance from the coordinate plane in the third axis’ direction using the , , or field (default value: 0; that is, no offset).

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to define the position of the plane by selecting a vertex. The plane’s position then contains that vertex. Click the button to toggle between turning ON and OFF the selections.

Select a planar face in the window that is parallel to the plane you want to create. The list below shows the selected face. Click the button to toggle between turning ON and OFF the selections. Specify an offset using one of the following settings in the list:

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(the default) to define the distance in the field. Default value: 0; that is, no offset. Enter a value to offset the plane along the normal of the planar face. The normal direction is indicated in the window, showing arrows in the corners of the visualization of the plane.

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to define the position of the plane by selecting a vertex. The plane’s position then includes the position of that vertex. Click the button to toggle between turning ON and OFF the selections.

To reverse the orientation of the plane, select the check box.

Select a planar edge (that is not straight) in the window that is parallel to the plane you want to create. The list below then shows the selected edge. Click the button to toggle between turning ON and OFF the selections.

Specify an offset using one of the following settings in the list:

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(the default) to define the distance in the field. Default value: 0; that is, no offset. Enter a value to offset the plane along the normal of the plane containing the edge. The normal direction is indicated in the Graphics window, showing arrows in the corners of the visualization of the plane.

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to define the position of the plane in the third direction by selecting a vertex. The plane’s position then includes the position of that vertex. Click the button to toggle between turning ON and OFF the selections.

To reverse the orientation of the plane, select the check box.

Use this plane type to orient the plane with a prescribed normal vector.

Under , in the , , and fields (SI unit: m), enter the components of the normal vector.

Under , from the list, choose (the default) or . For , enter the coordinates for a point on the plane in the , , and fields (SI unit: m). For , select a vertex in the geometry, or if available, use a user-defined vertex selection.

In each of the lists , , and , select a vertex by first clicking the corresponding button and then selecting a vertex in the window. This creates a plane parallel to a plane through the three vertices.

Specify an offset in the field (default value: 0; that is, no offset). The normal direction is indicated in the window, showing arrows in the corners of the visualization of the plane. Reverse the orientation of the plane by selecting the check box.

This choice creates a plane through the three points with the given coordinates.

Select the check box to add several planes which will be parallel to the one specified above. Enter the desired plane offsets in the field (using comma- or space-separated numbers), specifying the distances between each additional plane and the original plane. Both positive and negative values are allowed. Alternatively, use the button (

) to create an array of values. The orientation of the first plane determines the orientation of generated faces and on what side additional planes are placed. Reverse the offset direction by selecting the check box (the positive direction is the normal direction of the first plane).

Use the option to fill closed regions formed by the edges in the intersection plane (default ON). This results in planar faces meshed with a free triangular mesh. For a domain selection, faces will only be created inside the selected domains. A warning that no faces could be created may be expected if only one boundary has been selected. To get rid of the warning, clear the check box.

	Creation of intersection faces is not supported for assembly pair boundaries and other entities that are geometrically coinciding but non-adjacent.

Intersection of boundary and edge elements can result in short mesh edges, relatively small elements, and elements of poor element quality. To improve the quality of the mesh, cleanup is done by snapping mesh vertices and collapsing short mesh edges. Mesh vertices on the intersected faces and edges can be moved (snapped) to the plane to ensure a planar intersection when cleanup is performed. To decrease the amount of snapping performed, lower the .

Mesh vertices are snapped to the intersection plane if both of the following apply:

Use the list to control the snapping distance by choosing (the default), , or . Choose to enter a value in the field. This value is relative to the length of the longest side of the mesh bounding box. Select to specify a value in the field. When the operation is built with either of the settings or , the values in the (for only) and fields are automatically updated to be an average of the distances the mesh vertices were actually moved.

Select the check box to allow short mesh edges to be removed. Mesh edges shorter than the specified will be collapsed as long as this doesn’t result in an invalid mesh.