Partition Objects

The node (

) provides a way to partition geometry objects as a Boolean operation. Partitioning geometry objects can be useful to create separate domains, to introduce an interior boundary, or to cut of a part of the original geometry that is not needed for the analysis, for example. Using the node, you can partition a target object using a set of tool objects (geometry objects that are only used to partition — or tool — other geometry objects) or using an (infinite) plane defined by a node (you do not need to draw anything in the work plane). The output of a node’s partitioning operation includes the same number of objects as the input to the partitioning. To add it to a model, in the toolbar, from the (

) menu, select . You can also right-click the or a node to add this from the submenu. Then enter the properties of the partitioning operation using the following sections:

In the list, add the geometry objects that you want to apply a partition operation on. Click the button to toggle between turning ON and OFF the selections.

Select the check box to use the selected geometry objects to partition for further geometry operations.

From the list (3D only; for 2D, only objects can be used), select (the default) to partition using the geometry objects that you add to the list below, or select to partition using any of the added work planes.

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If you select , add the geometry objects that you want to use as tool object to the list. Click the button to toggle between turning ON and OFF the selections. Those geometry objects are only used to partition the geometry objects in the list and are not included in the finalized geometry used for defining materials and physics nodes. Select the check box to use the selected tool objects for further geometry operations.

You can change the settings for the list if you experience problems with the partition operation. Geometric entities that have a distance less than the repair tolerance are merged.

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The default value in the list is , which for 3D objects represented using the CAD kernel determines the repair tolerance internally. For 3D objects represented using the COMSOL kernel, and for 2D and 1D objects, means a relative repair tolerance of 10−6.

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Choose to enter a value for the field (the default is determined by the main node’s setting). This value is relative to the largest absolute value of the coordinates of all input objects.

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Choose to enter a value for the field (the default is determined by the main node’s setting; SI unit: m). This value uses the same unit as the geometry sequence’s length unit.

When you build this feature, the relative and absolute repair tolerances are set to the values that are used (with a precision of two digits), which can be useful when you have set to .

Select the check box to create predefined selections (for all levels — objects, domains, boundaries, edges, and points — that are applicable) in subsequent nodes in the geometry sequence. To also make all or one of the types of resulting entities (domains, boundaries, edges, and points) that the resulting objects consist of available as selections in all applicable selection lists (in physics and materials settings, for example), choose an option from the ( if in a geometry part; if in a work plane’s plane geometry) list: , , , , or . The default is , which is suitable for use with materials and physics defined in domains. For use with a boundary condition, for example, choose . These selections do not appear as separate selection nodes in the model tree. Select to not make any selection available outside of the geometry sequence. From the list, choose a color for highlighting the resulting objects selection. See Selection Colors.