AORDER | — | Mesh by ascending area size order.
Set Value to ON to mesh smaller areas
first. Using this results in finer meshes in critical areas for volume
meshes; this can be used for cases where SMRTSIZE does not mesh as needed. Default is OFF. |
EXPND | — | Area mesh expansion (or contraction)
option. (This option is the same as SMRTSIZE,,,EXPND.)
This option is used to size internal elements in an area based on
the size of the elements on the area's boundaries. Value is the expansion (or contraction) factor. For
example, issuing MOPT,EXPND,2 before meshing an
area will allow a mesh with elements that are approximately twice
as large in the interior of an area as they are on the boundary. If Value is less than 1, a mesh with smaller elements
on the interior of the area will be allowed. Value for this option should be greater than 0.5 but less than 4.
Value defaults to 1, which does not
allow expansion or contraction of internal element sizes (except when
using AESIZE sizing). If Value = 0, the default value of 1 will be used. The actual size of the
internal elements will also depend on the TRANS option (or upon AESIZE or ESIZE sizing, if used).
|
TETEXPND | — | Tet-mesh expansion (or contraction)
option. This option is used to size internal elements in a volume
based on the size of the elements on the volume's boundaries. Value is the expansion (or contraction)
factor. For example, issuing MOPT,TETEXPND,2 before
meshing a volume will allow a mesh with elements that are approximately
twice as large in the interior of the volume as they are on the boundary.
If Value is less than 1, a mesh with smaller
elements on the interior of the volume will be allowed. Value for this option should be greater than 0.1 but
less than 3.
Value defaults to 1, which does not
allow expansion or contraction of internal element sizes. If Value = 0, the default value of 1 will be used. If Value is greater than 2, mesher robustness may be affected.
The TETEXPND option is supported for both the VMESH and FVMESH commands. Tet-mesh expansion is the
only mesh control supported by FVMESH. |
TRANS | — | Mesh-transition option. Controls
how rapidly elements are permitted to change in size from the boundary
to the interior of an area. (This option performs the same operation
as SMRTSIZE,,,,TRANS.) Value is the transitioning factor. Value defaults to 2.0, which permits elements to approximately double
in size as they approach the interior of the area. (If Value = 0, the default value of 2 will be used.) Value must be greater than 1 and, for best results,
should be less than 4. The actual size of the internal elements will
also depend on the EXPND option (or upon AESIZE or ESIZE sizing, if used).
For a quad mesh with any element size, this option has no effect,
as the program strictly respects any face size to ensure the most
uniform quad mesh possible. To obtain a graded mesh using this option,
apply LESIZE to the lines of the desired face. |
AMESH | — | Triangle surface-meshing option.
Valid inputs for Value are: DEFAULT | — | Allows the program to choose which triangle mesher
to use. In most cases, the program chooses the main triangle mesher,
which is the Riemann space mesher. If the chosen mesher fails for
any reason, the program invokes the alternate mesher and retries the
meshing operation. | MAIN | — | The program uses the main triangle mesher (Riemann
space mesher), and it does not invoke an alternate mesher if the main
mesher fails. The Riemann space mesher is well suited for most surfaces. | ALTERNATE | — | The program uses the first alternate triangle mesher
(3-D tri-mesher), and it does not invoke another mesher if this mesher
fails. This option is not recommended due to speed considerations.
However, for surfaces with degeneracies in parametric space, this
mesher often provides the best results. | ALT2 | — | The program uses the second alternate triangle mesher
(2-D parametric space mesher), and it does not invoke another mesher
if this mesher fails. This option is not recommended for use on surfaces
with degeneracies (spheres, cones, etc.) or poorly parameterized surfaces
because poor meshes may result. |
|
QMESH | — | Quadrilateral surface meshing option.
(Quadrilateral surface meshes will differ based on which triangle
surface mesher is selected. This is true because all free quadrilateral
meshing algorithms use a triangle mesh as a starting point.) Valid
inputs for Value are: DEFAULT | — | Let the program choose which quadrilateral mesher
to use. In most cases, the program will choose the main quadrilateral
mesher, which is the Q-Morph (quad-morphing) mesher. For very coarse
meshes, the program may choose the alternate quadrilateral mesher
instead. In most cases, the Q-Morph mesher results in higher quality
elements. If either mesher fails for any reason, the program invokes
the other mesher and retries the meshing operation. (Default.) | MAIN | — | The program uses the main quadrilateral mesher (Q-Morph
mesher), and it does not invoke the alternate mesher if the main mesher
fails. | ALTERNATE | — | The program uses the alternate quadrilateral mesher,
and it does not invoke the Q-Morph mesher if the alternate mesher
fails. To use the alternate quadrilateral mesher, you must also select MOPT,AMESH,ALTERNATE or MOPT,AMESH,ALT2. |
|
VMESH | — | Tetrahedral element meshing option.
Valid inputs for Value are: DEFAULT | — | Let the program choose which tetrahedra mesher to
use. | MAIN | — | Use the main tetrahedra mesher (Delaunay technique
mesher). (GHS3D meshing technology by P. L. George, INRIA, France.)
For most models, this mesher is significantly faster than the alternate
mesher. | ALTERNATE | — | Use the alternate tetrahedra mesher (advancing front
mesher). This mesher does not support the generation of a tetrahedral
volume mesh from facets (FVMESH). If this mesher
is selected and you issue the FVMESH command, the
program uses the main tetrahedra mesher to create the mesh from facets
and issues a warning message to notify you. |
|
SPLIT | — | Quad splitting option for non-mapped
meshing. If Value = 1, ON, or ERR, quadrilateral
elements in violation of shape error limits are split into triangles
(default). If Value = 2 or WARN, quadrilateral
elements in violation of either shape error or warning limits are split into triangles. If Value = OFF, splitting does not occur, regardless of
element quality. |
LSMO | — | Line smoothing option. Value can be ON or OFF. If Value = ON, smoothing of nodes on area boundaries is performed during
smoothing step of meshing. During smoothing, node locations are adjusted
to achieve a better mesh. If Value = OFF
(default), no smoothing takes place at area boundaries. |
CLEAR | — | This option affects the element
and node numbering after clearing a mesh. If Value = ON (default), the starting node and element numbers will be the
lowest available number after the nodes and elements are cleared.
If Value = OFF, the starting node and
element numbers are not reset after the clear operation. |
PYRA | — | Transitional pyramid elements option.
Value can be ON or OFF. If Value = ON (default), the program automatically creates
transitional pyramid elements, when possible. Pyramids may be created
at the interface of tetrahedral and hexahedral elements, or directly
from quadrilateral elements. For pyramids to be created, you must
also issue the command MSHAPE,1,3D (degenerate
3-D elements). If Value = OFF, the program
does not create transitional pyramid elements. |
TIMP | — | Identifies the level of tetrahedra
improvement to be performed when the next free volume meshing operation
is initiated (VMESH, FVMESH).
(For levels 2-5, improvement occurs primarily through the use of
face swapping and node smoothing techniques.) Valid inputs for Value are: 0 | — | Turn off tetrahedra improvement. Although
this value can lead to faster tetrahedral mesh creation, it is not recommended because it often leads to
poorly shaped elements and mesh failures. | 1 | — | Do the minimal amount of tetrahedra
improvement. (Default.) This option is supported by the main tetrahedra
mesher only [MOPT,VMESH,MAIN]. If the alternate
tetrahedra mesher (MOPT,VMESH,ALTERNATE) is invoked
with this setting, the program automatically performs tetrahedra improvement
at level 3 instead (MOPT,TIMP,3). | 2 | — | Perform the least amount of swapping/smoothing.
No improvement occurs if all tetrahedral elements are within acceptable
limits. | 3 | — | Perform an intermediate amount of swapping/smoothing.
Some improvement is always done. | 4 | — | Perform the greatest amount of swapping/smoothing.
Meshing takes longer with this level of improvement, but usually
results in a better mesh. | 5 | — | Perform the greatest amount of swapping/smoothing,
plus additional improvement techniques. This level of improvement
usually produces results that are similar to those at level 4, except
for very poor meshes. | 6 | — | For linear tetrahedral meshes, this
value provides the same level of improvement as MOPT,TIMP,5. For quadratic tetrahedral meshes, this value provides an
additional pass of cleanup. This value is supported for both the
main (MOPT,VMESH,MAIN) and alternate (MOPT,VMESH,ALTERNATE) tetrahedra meshers. |
|
STAT | — | Display status of MOPT settings. Value is ignored. |
DEFA | — | Set all MOPT options
to default values. Value is ignored. |