Sector Symmetry Pair
Use a Sector Symmetry Pair node () to specify a pair between two domains while modeling a sector of a geometry and one of the domains is rotating around the sector center. If you select sector symmetry pairs instead of identity pairs in a Sector Symmetry feature in a physics interface, the sector settings in the physics feature are no longer needed. You instead specify them in the sector symmetry pair.
The easiest way to set up a sector symmetry can often be to use the identity pair that is added automatically for an assembly geometry, and in its settings select the Manual control of selections and pair type checkbox and then change the pair type to Sector symmetry pair. You then do not need to identify the pair boundaries in a separate Sector Symmetry Pair node.
Go to Pair Name for information about the Settings window Pair name. Also see Settings and Properties Windows for Feature Nodes.
Pair Type
The default Pair type is Sector symmetry pair, or you can select Identity pair, Contact pair, or General Contact pair. See Pair Type for more details.
Source Boundaries and Destination Boundaries
The destination boundaries should overlap the source boundaries. The condition that connects the physics nodes on the destination and source boundaries is specified in the physics interface. For example, it can be a constraint that constrains a dependent variable (temperature, for example) on the destination side to be equal to a dependent variable on the source side. In this case, the boundaries and domains on either the source or destination, or both sides, are rotating around an axis, so the boundaries do not need to be in contact in all cases but rather for some angles only.
To define the source or destination boundaries, from the Selection lists, choose Manual, All boundaries, or any other available selection for the boundaries on the source or destination side. If Manual is selected, click in the Graphics window to add boundaries to the Selection section. If required, click the Swap Source and Destination button () to swap the source boundaries and the destination boundaries.
Click the Activate Selection button to toggle between turning ON and OFF selections directly in geometry, for example. Such selections also become active when you choose Manual from the Selection list.
Sector Symmetry Settings
The inputs needed in the sector symmetry pair are the number of sectors, the rotation axis base point, and (in 3D) the axis of rotation. These settings can be computed automatically from the geometry in simple cases. Otherwise, you must provide them by choosing Manual from the Sector symmetry settings list (default: Automatic). When you choose Manual, also specify the following:
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 Number of sectors (default: 2)
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 Rotation axis base point: Define the base point for the rotation in the x, y (2D and 3D), and z (3D) fields.
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 Axis of rotation (3D only): Define the axis of rotation in the x, y, and z fields.
Frame
Use this settings to control the frame to use for the pair. Choose Spatial (x, y, z) (the default), Mesh (Xm, Ym, Zm), Geometry (Xg, Yg, Zg), or Material (X, Y, Z).
Advanced
The value in the Extrapolation tolerance field is used to find out if two points are in contact or not (default: 0.05).