The Sources panel (shown below) is primarily used to adjust Spacing and Decay values for your existing,
selected sources. One or more sources must be selected for the Sources command to be available.
Sources are a separate type of entity which can be used to control grid density in the isotropic, not T-Rex layers, region of unstructured blocks. Sources
can also be used to adapt structured and voxel blocks and to align the cells of unstructured domains in a general direction. Sources are completely
independent of grid and database entities. Sources can also be used to adapt the boundaries of all block types. For more on boundary adaption
see Boundary Conditions for unstructured blocks
or Boundary Conditions for structured blocks.
Adjust your source Spacing and Decay using the Sources panel.
The next image illustrates an Examine cut through an unstructured block with a cylindrical source affecting its interior. In this example the source
spacings vary from 0.5 at the top, in this image, of the cylinder to 1.0 at the bottom.
Sources can be used to control point density of the isotropic tets in unstructured blocks.
Several creation tools can be used to create source entities. The Create, Draw Shapes command can be used to create 3D source entities such as boxes
or cylinders. The Create, Draw Curves command and Create, Points commands can also be used to create source
entities. Newly created sources will have default values for spacing and decay set automatically from those found in the Defaults
(Gui, Interface, Panels, Defaults). Those values can be updated here or in
the Grid, Solve, Attributes command tab (Grid, Solve, Unstructured blocks).
Spacing and decay values are applied at the begin and end locations of each source. These locations are determined by the order in which the ends of the
source was originally created. In the Sources panel at top there is a table listing current values of spacing and decay for the selected source. If
multiple sources are selected, average values will be displayed.
Below the table the Beginning/Constant Values frame provides text fields to input new values of Spacing and Decay for the
beginning of the currently selected source or sources. If the selected source has been set to type Constant (see below), it will only be necessary to
input the values in this frame for the entire source. Likewise, additional fields are available in the Ending Values frame to enter values for the
end of the currently selected source or sources.
Note that source influence on block distribution is achieved by converting a source to a point cloud. This point cloud representation will increase in
density as spacing values get smaller. This in turn increases overhead in the block solver and extends the time necessary for the solver to initialize a block
interior. Therefore it is prudent to start on the conservative side of spacing values initially. The solver will allow you to stop the initialization process
if it appears to be taking too long to complete.
Start Interactive Mode allows graphical adjustment of the source spacing values.
Below the input frames you will find the Reverse command allowing you to swap beginning and ending values for the currently selected
sources. Start Interactive Edit puts you into a graphical mode for adjusting Spacing values at the beginning and ending locations. A relatively sized
ring can be clicked and dragged in the Display to adjust. The new spacing is dynamically updated in the table for the selected location. When
finished adjusting, click Stop Interactive Edit to end the graphical interaction mode.
Finally, at the bottom of the Sources panel you will find the Spacing Type frame, which shows and allows you to select the type of
distribution used by a source.
- Constant: It changes the source to single valued for spacing and decay throughout the source entity. This will require only a single input
for each value, which is the reason the Beginning/Constant Values frame is labeled as such.
- Parametric (default): Varies the spacing linearly along the source from beginning to end.
- Axis to Perimeter: Varies the spacing linearly from the axis of the source to its perimeter.
- Center to Perimeter: Uses a point location and vary the spacing linearly from that point to the entire boundary of the source.
- Align Only: This option is only available for source curves and it specifies that a given source curve should be used only for domain
alignment purposes (i.e. no grid refinement). Refer to the Surface Shape
section for more information on domain source alignment.
- General: Is a special case shown only to indicate what are point cloud sources. Point cloud sources can only be created currently using