New Trelis Features



Improved Mesh scaling

The Scale Mesh command has been significantly improved. Originally released in Trelis 15.2, the command syntax is now:

Scale Mesh [Multiplier <value>] [minimum <value>] [{SWEPT_BLOCKS|structured_blocks}] [feature_angle <value>] [force_structured in {[volume <ids>] [surface <ids>]}]

In the GUI, Mesh Scaling is found on the Command Panel under Mesh-Volume-Refine Mesh. Choose Mesh Scaling from the drop-down menu.

The Scale Mesh command globally refines or coarsens the current hexahedral mesh in CUBIT based upon the input Multiplier. For example, if a multiplier of 2.0 is specified, the scale mesh command attempts to double the number of hexahedral elements in the mesh, with the new elements spread evenly across the entire model, effecting global refinement. Similarly, if a multiplier of 0.75 is specified, the scale mesh command attempts to reduce the number of hexahedral elements in the mesh by 25%, spread evenly across the model.

New for Trelis 16.0 are the arguments swept_blocks, structured_blocks, feature_angle, and force_structured. These new arguments provide user controls to ensure a more evenly distributed refinement/coarsening across model. In Trelis 16.0, mesh scaling is no longer required to honor every mesh singularity in favor of a more evenly distributed refinement. Specify structured_blocks if you desire the 15.2 behavior of honoring every mesh singularity. The 16.0 default, swept_blocks, will provide a smoother refined mesh as illustrated in the images below.

The picture below shows the scaled mesh at various multipliers.

(Image courtesy of Sandia National Laboratories)

Improved boundary layers

Trelis CFD 16.0 and Trelis Pro 16.0 support boundary layer meshing. Based on feedback from our CFD users Trelis 16.0 includes several enhancements to boundary layer processing. Below is a summary of the enhancements and improvements.

Improved quality

Overall element quality has been improved. In the example below the poorest element quality was 0.158 Scaled Jacobian before the improvements. The same model now contains no elements with quality lower than 0.463 Scaled Jacobian.

Boundary layers on merged surfaces

In some circumstances boundary layers on merged surfaces produced inverted pyramid elements, as seen in the left-hand image. The boundary layer has been improved as shown in the right-hand image.

Boundary layers projected into volume

In some circumstances, a boundary layer should project from a vertex into a volume. The boundary layer has been improved as shown in the right-hand image.

Limited support for incrementally adding boundary layers

Trelis CFD 16.0 and Trelis Pro 16.0 includes limited support for adding boundary layers, incrementally, while meshing. It should be noted this feature is new and may not work in all situations. Below are images showing two cylinders. The green and yellow cylinders share a common surface. The green cylinder contains a boundary layer and that cylinder is meshed. A boundary layer is added to the yellow cylinder and that cylinder is meshed. The existing boundary layer and mesh on the green cylinder is respected and preserved.


The green cylinder includes a boundary layer. The green cylinder is meshed.


A boundary layer is added to the yellow cylinder and it is meshed. The existing mesh on the green cylinder is respected.

Improved classic geometry adaptive sizing

The GUI for setting the parameters for the geometry adaptive sizing function has been simplified to easily display commonly used controls.

Unimprint command

New on the Imprint/Merge panel is the Unimprint command that will remove the imprinted surfaces created with the Imprint command.

Improved tri and tetmesher

Trelis 16.0 integrates Distene's most recent MeshGems-CADSurf and MeshGems-Tetra technologies. These technologies are more robust, reliable, and faster than previous versions, producing better meshes on complex geometries.

The tetmesher has the ability to automatically adapt element sizes based on geometric features such as curvature and narrow regions. User settings allow for changing the sensitivity of the adaptive mesh to better approximate the underlying geometry.


Hex Mesh Cleanup

A new hexahedral mesh cleanup capability has been added to Trelis 16.0. This capability improves mesh quality when the mesh contains columns of "high-angle" hexes on volume boundaries. A combination of column operations is done to add three additional columns of hexes to mitigate the high angle.

Cleanup Volume <id_range> [angle <value=150>]

In the GUI, hex mesh cleanup is can be found on the Command Panel under Mesh-Volume-Mesh Cleanup

Boundary hexes with adjacent faces having a dihedral angle greater than the specified angle (default is 150 degrees) will be cleaned up. See Mesh Cleanup in the documentation.

(Image courtesy of Sandia National Laboratories)

Post-meshing button

On the right-side of the top-level mode buttons is the "Post Meshing Tool Launch" button. A typical use is to launch an external, executable program.

Trelis now includes an additional field to the dialog that configures the launch. The dialog is found under Tools/Options/Post Meshing.

In addition to specifying the executable's location, name, and input arguments, users may also specify a script which will be run before launching the executable. A use may include exporting the model to a known location. (See Trelis User Manual for more information.)


Upgrade to the ACIS 25 geometry kernel

Trelis 16.0 includes an update to the ACIS solid modeling libraries to version R25 SP1. The new version contains various improvements and bug fixes. As with any upgrade to the ACIS solid modeling libraries, there is the potential for geometry id changes in Trelis compared to earlier versions.

(See IDless Journal Files in the Trelis User Manual for information on updating old journal files to work with the latest Trelis version.)

New Entity Align command panel

An Align (3 Step) command panel has been added to the GUI making geometry alignment much easier and more intuitive. The command panel is available for volumes, surfaces, curves, and vertices. See Align in the documentation.

New Extended Selection dialog

The Extended Selection Dialog is accessible any time a geometry entity is selected in the graphics window. The dialog leverages the combination of Python™ and the CubitInterface class to give users a very powerful mechanism for creating and managing custom selection filters.

When you use Extended Selection for the first time, you must load your custom filters, written in Python, and check the filters to be included in the context menu.

Use the pull down menu to select a filter. Click on an entity in the Source Selection list. Geometric entities that fit the filter criterion will be shown in the Target Entities list.

See Extended Selection Dialog in the documentation.

New surface overlap check tool

Trelis cannot produce a contiguous mesh on a model that contains overlapping surfaces. Trelis now includes a button, located on the top tool bar as two overlapping purple circles, that quickly locates overlapping surfaces.



Improved mesh based geometry creation speed

The speed to create mesh-based geometry has been improved.

Fluent exporter supports 3D surface mesh

Now Trelis allows you to export Fluent 3D surface meshes with the improved Fluent export.

FEA/CFD specific importers/exporters

Depending on the version of Trelis you have, the importers and exporters will allow you to use the format for your solver.

Graphics, Utilities, etc.

Improved graphics performance

Several areas of the graphics have been refactored in order to improve speed and rendering efficiencies. Trelis 16.0 has faster response times with larger models and interactive graphics operations. For example, a certain model with 1000 volumes has an interaction time is about 2.7 times faster. Trelis has also been enhanced to use multiple threads while generating a graphical representation of the geometry model. This is usually noticeable when opening or importing large models.

New quality tool on Properties Page

The quality tool on the properties page will now respect the quality defaults in the options panel. In other words, all of the quality metrics selected in the options panel will be executed when the user clicks on the Quality Tool.

New keystroke shortcuts to View Points

Users can use new keystroke shortcuts to change the view point of the model.

RLM deactivation

The RLM activation utility rlm_activate has been enhanced with a new option for deactivating a license. Users can transfer a license from one computer to another by deactivating their license using a terminal window and reactivating the license on the new computer.


Release Notes.

Click on the Trelis version to expand the list.

Trelis 16.0
Issue Description
[SM-277] Boundary Layers are skewed if applied to a meshed volume.
[SM-426] Duplication of the geometric entities
[SM-613] Meshing BoundaryLayer fails with already existing mesh
[SM-628] ITEM tutorial problem
[SM-629] meshing error on tutorial getting started
[SM-659] Crash in tetmeshing
[SM-733] working directory cannot be inherited at startup
[SM-737] Save file dialog doesn't manage cub vs trelis well
[SM-748] Fix pick widget type for the sideset panel
[SM-755] Crash when picking sweep target surface after setting trimesh scheme on any surface
[SM-758] Newly created group will not accept default "GroupName" as a name, puts %1 as name
[SM-763] more command panel link problems
[SM-764] HDF5 file doesn't save with Japanese in filepath
[SM-391] Support CGNS (CFD General Notation System) file format
[SM-565] Add "Extract Sheet Edge" Command to Mesh Sheet Refinement GUI
[SM-602] Add Find Overlap to GUI
[SM-652] Classic geometry adaptive GUI simplification and improvement
[SM-658] Improved mesh based geometry creation speed
[SM-660] Change the label from "Delete" block/sideset/nodeset to "Remove"
[SM-669] Add scaled jacobian metric to tri-quality
[SM-677] Create interior wall between solid and fluid cfd media in Fluent exporter
[SM-680] Block, Sideset, Nodeset renumber GUI
[SM-682] Add improved tri and tet meshing command panels to the GUI
[SM-709] Add pyramid support to Nastran exporter
[SM-716] Add a unimprint or remove imprint command in the Geometry-[Entity]-Imprint/Merge
[SM-739] Add examples in the Help
[SM-756] Add keystroke for View Points for Back, Bottom, and Left views.
[SM-444] RLM deactivation option in the activation utility
[SM-623] Add legacy .cub file to the Save and Save As file formats
[SM-651] Improved mesh scaling
[SM-676] Make the quality tool button on the properties page honor metric selections in options panel
[SM-726] Add capability for extended selection and picking to the GUI
[SM-740] Add a context menu to the idless signature field in properties pages to support copying the contents
[SM-743] Add new Hex cleanup command and GUI to Trelis
[SM-747] Add a "Set Last Directory" item to the File menu
[SM-404] Move - Double Jeopardy
[SM-430] fea bc panels confusing
[SM-511] meshgems CADSurf issues
[SM-576] crash saving .cub file
[SM-577] Add NetCDF4/HDF5 Exodus option in GUI
[SM-645] Upgrade ACIS to r25 and Translators
[SM-675] Clean up BC command panels
[SM-711] Add MeshGems version number to 'version' command and to the help/about dialog
[SM-730] Trelis 16.0 Help Link
[SM-735] command panel help links
[SM-774] Command Replicate on all Sidesets in Tree
Trelis 16.0.1
Issue Description
[SM-584] Exported OpenFOAM Case File Doesn't Run in OpenFOAM
[SM-639] Crashing Bug: Create ACIS from mesh-based geometry
[SM-733] working directory cannot be inherited at startup
[SM-757] group dropdown menu in tree
[SM-773] Disk STL file crashes when tetmeshing on Windows
[SM-775] Uncaught exception when creating ACIS geometry
[SM-779] Lists Created CFD_BC as an ' Unrecognized Identifier' when selected in the Tree
[SM-761] Add the ability to export to a legacy .cub file from the GUI
[SM-767] Add a command to modify the type of a cfd boundary condition
[SM-770] Allow users to change a cfd bc type in the property pages
[SM-752] Turn the Align (3 Step) panel functionality into a command
Trelis 16.0.2
Issue Description
[SM-795] Volume doesn't appear in tree after sweep surface
[SM-797] Fixed unable to rename sheet body
[SM-772] Added split curves at discontinuities option
Trelis 16.0.3
Issue Description
[SM-803] Fixed invalid tet mesh
[SM-806] Fixed tet meshing reporting invalid errors
[SM-805] Fix sorting of elements in Model Tree window

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