Symmetry for Surface-to-Surface Radiation
Use this node to compute view factors on only a part of a symmetric geometry to improve efficiency, by defining either one symmetry plane in 2D, 2D axisymmetric, and 3D components, multiple perpendicular symmetry planes in 2D and 3D components; or sectors of symmetry in 2D and 3D components. In addition, a reflection plane can be defined inside each sector of symmetry. Table 6-4 summarizes the available options for each dimension.
Table 6-4: Options for symmetry definition, example with 5 sectors
Symmetry Type
2D
2D axisymmetric
3D
One Plane
Two Planes
Not applicable
Three Planes
Not applicable
Not applicable
Sectors
Not applicable
Sectors and Reflection
Not applicable
Symmetry for Surface-to-Surface Radiation
Depending on component’s dimension, select the Type of symmetry to be defined:
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In 2D components, select between Plane of symmetry (the default), Two perpendicular planes of symmetry, or Sectors of symmetry.
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In 2D axisymmetric components, only the Plane of symmetry option is available.
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In 3D components, select between Plane of symmetry (the default), Two perpendicular planes of symmetry, Three perpendicular planes of symmetry, or Sectors of symmetry.
Depending on the Type of symmetry selected from the list and on the dimension, further settings are required.
Plane of symmetry
The coordinates of the points defining the plane should be set:
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In 2D components, the symmetry plane is defined by two points. Set the x and y coordinates of the First point on plane of reflection and of the Second point on plane of reflection.
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In 2D axisymmetric components, the symmetry plane is parallel to the z=0 plane. Set the z coordinate of plane of reflection, zsym.
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In 3D components, the symmetry plane is defined by three points. Set the x, y, and z coordinates of the First point on plane of reflection, the Second point on plane of reflection, and the Third point on plane of reflection.
The Show the plane of symmetry check box is selected by default. Clear it to hide the plane in the Graphics window.
Two perpendicular planes of symmetry
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In 2D components, the planes intersection line is along the out-of-plane direction. The Point at the intersection of symmetry planes and the Rotation angle from Cartesian axis, θ, should be defined.
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In 3D components, the Planes intersection line can be set Along the x-axis, Along the y-axis, or Along the z-axis. A Point at the intersection of symmetry planes and the Rotation angle from Cartesian axis, θ, should be defined. The position of the point along the intersection line can be arbitrary as it does not change the planes definition. The direction of the angle θ can be checked on the figure displayed below the settings, for each case of alignment of the intersection line.
The Show the planes of symmetry check box is selected by default. Clear it to hide the planes in the Graphics window.
Three perpendicular planes of symmetry
The planes are parallel to the Cartesian axis. Only the Point at the intersection of symmetry planes should be defined.
The Show the planes of symmetry check box is selected by default. Clear it to hide the planes in the Graphics window.
Sectors of symmetry
The coordinates of the points defining the symmetry axis should be set:
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In 2D components, the symmetry axis is the out-of-plane vector, and the center of the symmetry must be defined. Set the x and y coordinates of the Point of central symmetry.
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In 3D components, the symmetry axis is defined by two points. Set the x, y, and z coordinates of the First point defining sector symmetry axis and the Second point defining sector symmetry axis.
Enter a value for the Number of sectors. This should be a numerical value greater or equal to 2.
If the Reflection for symmetrical sector check box is selected, set the coordinates of the Radial direction of reflection plane, u. This option may be used when each sector has itself a plane of symmetry.
The Heat Transfer with Surface-to-Surface Radiation Interface
Theory for Surface-to-Surface Radiation
Location in User Interface
Context menus
Heat Transfer with Surface-to-Surface Radiation>Global>
Symmetry for Surface-to-Surface Radiation
Surface-to-Surface Radiation>Global>Symmetry for Surface-to-Surface Radiation
More locations are available if the Surface-to-surface radiation check box is selected under the Physical Model section. For example:
Heat Transfer in Solids>Global>Symmetry for Surface-to-Surface Radiation
Ribbon
Physics Tab with Heat Transfer in Solids, Heat Transfer in Fluids, Heat Transfer in Porous Media, Heat Transfer in Building Materials, Bioheat Transfer, Heat Transfer with Surface-to-Surface Radiation, Surface-to-Surface Radiation or Heat Transfer with Radiation in Participating Media selected:
Global>Symmetry for Surface-to-Surface Radiation