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3.4.2 Hex Dominant Method Control

If you select the Hex Dominant method, a free hex dominant mesh is created. If you are interested in a
hex mesh, this option is recommended for bodies that cannot be swept. To preview any bodies that can
be swept, click Mesh on the Tree Outline and right-click the mouse. Select Show–› Sweepable Bodies
from the context menu to display bodies that fulfill the requirements of a sweepable body (other than
axis sweeping).
The Hex Dominant mesh method includes the following settings:

w Element Midside Nodes - Refer to Method Controls and ElementMidside Nodes Settings.
w Free Face Mesh Type - Determines the shape of the elements used to fill the body. Allows you to
choose Quad/Tri or All Quad. The default is Quad/Tri.
w Hex dominant meshing adds the most value under the following conditions:
w Meshing bodies with large amounts of interior volume.

w Meshing bodies that transition from sweepable bodies in a body that has been decomposed for
sweeping.
w However, it is better to use Body/Face Sizing to obtain more uniform face meshing, which leads to
morehexes by volume.
w Hex dominant meshing adds little value under the following conditions:
w Meshing thin complicated bodies (like a cellular phone case). The number of elements may
actually increase compared to a tetrahedron mesh since the element size must be much smaller f o r
this class of body when using hex dominant meshing to create well shaped hexes.
w A body is sweepable or can easily be decomposed to multiple sweepable bodies. The quality of a
swept mesh is usually superior to that of a hex dominant mesh.
w Models where fast transition of the mesh can result in poor solution accuracy (e.g. CFD models).
The Hex dominant approach can have very fast transitions at the core of the volume.

3.4.3 MultiZone Method Control

The MultiZone mesh method, which is a patch independent meshing technique, provides automatic
decomposition of geometry into mapped (sweepable) regions and free regions. When the MultiZone
mesh method is selected, all regions are meshed with a pure hexahedral mesh if possible. To handle
cases in which a pure hex mesh will not be possible, you can adjust your settings so that a swept mesh
will be generated in structured regions and a free mesh will be generated in unstructured regions.

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