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1.1 Release Notes:   Coreform Cubit 2022.4
1.1.1 U-splines
1.1.2 Graphical User Interface  Selection by entity name in graphics window  Select Chamfer Chain
1.1.3  Meshing  New Mass Increase Ratio metric added to Cubit  Geometry-Aware Spider Blocks
1.1.4  Geometry ACIS kernel updated to Version 2021.1.0.1
1.1.5 Sculpt New Sculpt options
1.1.6  Graphics, Utilities, etc.  Enhancements to Free Entity Selection Added support for Corvid Velodyne files  New Cubit  Interface functions
1.1.7  Defects Fixed in Coreform Cubit 2022.4
1.1.8  Enhancements in Coreform Cubit 2022.4
1.2 Release Notes:   Coreform Cubit 2020.2
1.3 Release Notes:   Coreform Cubit 2021.11
2022.4+26187-e1209cf7 Apr 14, 2022

1 New In Coreform Cubit

    1.1 Release Notes: Coreform Cubit 2022.4

      1.1.1 U-splines

      1.1.2 Graphical User Interface  Selection by entity name in graphics window  Select Chamfer Chain

      1.1.3  Meshing  New Mass Increase Ratio metric added to Cubit  Geometry-Aware Spider Blocks

      1.1.4  Geometry ACIS kernel updated to Version 2021.1.0.1

      1.1.5 Sculpt New Sculpt options

      1.1.6  Graphics, Utilities, etc.  Enhancements to Free Entity Selection Added support for Corvid Velodyne files  New CubitInterface functions

      1.1.7  Defects Fixed in Coreform Cubit 2022.4

      1.1.8  Enhancements in Coreform Cubit 2022.4

    1.2 Release Notes: Coreform Cubit 2020.2

    1.3 Release Notes: Coreform Cubit 2021.11

1.1 Release Notes: Coreform Cubit 2022.4

    1.1.1 U-splines

    1.1.2 Graphical User Interface  Selection by entity name in graphics window  Select Chamfer Chain

    1.1.3  Meshing  New Mass Increase Ratio metric added to Cubit  Geometry-Aware Spider Blocks

    1.1.4  Geometry ACIS kernel updated to Version 2021.1.0.1

    1.1.5 Sculpt New Sculpt options

    1.1.6  Graphics, Utilities, etc.  Enhancements to Free Entity Selection Added support for Corvid Velodyne files  New CubitInterface functions

    1.1.7  Defects Fixed in Coreform Cubit 2022.4

    1.1.8  Enhancements in Coreform Cubit 2022.4

1.1.1 U-splines

Coreform Cubit now supports U-spline construction on volumes meshed with the following mesh schemes:

1.1.2 Graphical User Interface  Selection by entity name in graphics window

The right click menu now provides an option to select entities that share the same name. It will select entities that have the same prefix up to the "@" character.  Select Chamfer Chain

When selecting a chamfer surface, the ‘select chamfer chain’ option is available in the right-click context menu.

1.1.3  Meshing  New Mass Increase Ratio metric added to Cubit

The Mass Increase Ratio metric is based on the timestep metric and can be used as a guide to determine how much an element’s mass can be scaled during analysis, to typically increase timestep. Users specify a minimum ‘target timestep’ and then use this metric to see how much an element’s mass will be scaled by to meet the specified timestep. Available for use on tets and hexes.  Geometry-Aware Spider Blocks

When creating spider blocks with the command:

Block <id> Joint [Vertex <id> | Node <id>] Spider {Surface|Curve|Vertex|Face|Tri|Node} <range> [preview][Element Type{ bar | bar2 | bar3 | BEAM | beam2 | beam3 | truss | truss2 | truss3 }]

and geometry (surface|curve|vertex) is referenced, the spider block is linked to that geometry, allowing the spider to update/regenerate the BAR elements if the mesh on the geometry is delete, remeshed, or translated.

1.1.4  Geometry ACIS kernel updated to Version 2021.1.0.1

The ACIS geometry kernel has been updated to Version 2021.1.0.1.

Note: Changes to the ACIS kernel can result in changes in entity ids, which may break journal files that rely on entity IDs. For mission-critical applications, we encourage users to either:

1.1.5 Sculpt New Sculpt options
1.1.6  Graphics, Utilities, etc.  Enhancements to Free Entity Selection

The ability to select free surfaces (sheet bodies) has been added to the command:

Select Free [surface <id_list>] [curve <id_list>] [vertex <id_list>] [add|remove] Added support for Corvid Velodyne files

Cubit now supports exporting files for use in Corvid Velodyne, via the command:

export velodyne ’<filename>’ [overwrite]  New CubitInterface functions

CubitInterface is Cubit’s python module that provides extensive capability for querying and modifying data in Cubit. The following functions were added to CubitInterface for version 2022.4.

Function Name





Get the bounding box for a list of entities.



Gathers connected surfaces to those specified, that use shared curves in an opposite sense.



Returns a list of lists of overlapping surfaces. First surface in each list overlaps with all others in that list.



Get the list of chamfer surfaces for a list of volumes



Returns the chamfer chains for a surface



Returns the collections of surfaces that comprise blend chains in the specified volumes. Filter by radius threshold



Returns the collections of surfaces that comprise chamfers in the specified volumes. Filter by thickness of chamfer



For every occurance of two overlapping curves, two curve ids are returned.



Get the list of overlapping surfaces for a single surface



For every occurance of a gap between volumes, two surfaces ids are returned.



Get the list of coincident vertex-vertex, vertex-curve, and vertex-surface pairs and distances from a list of volumes



Get the list of nearby volumes for a single volume within a specified distance



get default depth value for blunt tangency operation



Return whether a given surface is a chamfer



Returns the distance between two specified entities













Retrieve the current tetmesh global settings (Meshgems)









Retrieve the current trimesh global settings (Meshgems)



Get all ids of a geometry type with the prefix given by string.



Given a surface, returns all adjacent surface defining a hole.



Given a volume(s), returns the collections of surfaces that define holes.



Return whether the surface is part of a hole.



Given a node owned by a surface, returns the id of the best edge to collapse, so that the node is no longer on the surface.



Gets a list of continuous curves that have tangents with 180 degrees +/- and defined tolerance.



Computes the ‘n’ largest distance from the nodes of the first entity to the elements of the second

1.1.7  Defects Fixed in Coreform Cubit 2022.4

Ref #





Changed the default smoothing timeout from 10 minutes to 30 seconds


Better performance when importing cub files


Better performance when merging curves in GUI



Blocks of dimension 0 and 1 not highlighting correctly



Fix meshing quartered sphere with polyhedron scheme.



Cubit selection monitor doesn’t list mesh elements



Consolidating excessive printouts to terminal on some operations (regularize and delete mesh)



Fix for crash in tolerant imprinting.


Resolve issue with Locate command not working from right-click.


Allow local developers to turn off PyQt.


Added better support for "face" type in CubitInterface.


Fixed crash with swept curve.


Allow Cubit Learn login while importing Cubit into Python.


Fixed bug with named free curves.


Fixed sculpt failure due to inconsistent login cache path on Windows.


Fixed Cubit Learn login from sculpt error.

1.1.8  Enhancements in Coreform Cubit 2022.4

Ref #




When importing a ACIS file (.sat/.sab) added ability for Cubit to read in generic attributes with name PTCName on bodies and volumes


connected_sets option added to remove surface command to allow for more robust surface removal


The collapse edge/tri/tet commands can take multiple ids.


Users can globally control the minimum edge length created during triangle meshing (trimesh scheme) with the command: [Set] Trimesher Minimum Size <val>


Higher order nodes taken into account when computing element volume metric for hexes and tets.


Surface meshing scheme ‘Hole’ now accepts negative bias, switching bias direction.


Performance and robustness increase when importing mesh-based geometry models containing many hardlines.


Allow better capture of STL vertices with the capture=5 option.


Quality improvements interface of domain boundary and level-set surfaces. Adding grid cells in special cases.


More robustness to enforce periodicity.


Bugs in defeaturing, when not retaining void mesh.


Added support for surface geometry export when exporting .cdb files.

1.2 Release Notes: Coreform Cubit 2020.2

1.2.1 Graphical User Interface New Geometry Power Tool Diagnostics and Solutions


Figure 1:


Figure 2:

The Geometry power tool includes interactive diagnostics and solutions for defeaturing and repairing CAD models. New diagnostic tests have been added along with rapid solutions for repair. Updated and expanded diagnostics categories include Traits and Assembly Checks. New Command Panel Navigation Method


Figure 3:


Figure 4:

A new, optional, method for navigating the command panels has been added. This new option can be toggled on and off under Tools > Options > Command Panels. The obvious benefit of using this “breadcrumb” navigation method is gaining additional vertical space for command panels which will eliminate the need for scrolling in many cases. Support for Dark Mode

Support for Dark Mode has been added to Cubit 2020.2. Display Volume Overlaps and Neighbors from Context Menu


Figure 5:

Two new options are available in the graphics window when volumes are selected: Tetmesh and Trimesh GUI Command Panels

A new command panel for setting options for the tetmesh scheme is now available supporting all new local and global options for tetrahedral meshing. This panel now includes two separate tabs for setting options for surface meshing and volume mesh options. The trimesh panel has also been updated in a similar manner for setting options for the trimesh scheme. Reduce Bolts Command Panel


Figure 6:

The new reduce command (described below) uses a new command panel to rapidly set up parameters to simplify and assign boundary conditions to bolt connectors. Access the Reduce options in the command panels by clicking on Mode/Geometry > Entity/Volume > Action/Modify and using the dropdown to select Reduce. Meshing New Meshing Collapse Commands

The following commands are good for collapsing low quality tets and triangles. The user specifies a mesh entity to collapse and optionally a metric. The operation attempts to collapse the mesh entity, ensuring that the quality of surviving neighbor mesh entities does not degrade lower than the mesh entity getting collapsed. The specified metric is used to determine quality. If not specified, "Scaled Jacobian" is used.

If the collapse can not be done without degrading quality, no collapse is performed. To collapse triangles, use the first two commands.

Only triangle and tets can be collapsed, not faces and hexes.

collapse edge <id> [scaled jacobian|aspect ratio|shape|shape and size] collapse tri <id> [scaled jacobian|aspect ratio|shape|shape and size] collapse tet <id> [altitude|aspect ratio|aspect ratio gam|distortion|inradius|jacobian|normalized inradius|node distance|scaled jacobian|shape|shape and size|timestep]


Figure 7: Enhancements to Meshedit Command

The [keep node<id>] option indicates which node to collapse the edge to. The [compress_ids] option was also added to preserve the previous behavior of compressing the mesh id space after the collapse.

meshedit collapse edge <id> [keep node <id>] [compress_ids] Mesh Intersection Group Naming

A new option was added to the find mesh intersection command to allow naming the group created containing the intersecting mesh. If no group name is specified, the group is named mesh_intersect for 3D elements and surf_intersect for 2D elements.

find mesh intersection {block|body|surface|volume} <id_list>> [with {block|body|surface|volume} <id_list>] [low <value=0.0001>] [high <value=0.0001>] [exhaustive] [worst <num_worst>] [draw] [log] [group <’name’>] Normalized Inradius Metric for tet10 Elements

A new quality metric normalized inradius is now included as a standard option for all quality commands that affect tets and tris. It is intended to measure quality of TETRA10 and TRI6 elements, but can also measure linear (TETRA4, TRI3) elements. While most tet metrics, such as the default Shape, only take into account the 4 corner nodes of the tet, the normalized inradius uses the ten nodes of the tet. This is especially useful when measuring quality for a coarse tet mesh at curved surfaces where mid-edge-nodes can be projected to geometry distorting the elements. An example of using the new metric in a command to display the mesh quality is as follows:

quality volume all normalized inradius draw mesh New Node Constraint Options

When tet meshing with TETRA10 elements or setting a block element type to TETRA10, the mid-edge nodes on the surfaces can be projected to follow the geometry. In some cases, those projections can form an invalid or poor quality element when the linear version of the elements would otherwise be acceptable. Previously, Cubit provided the set node constraint command to control mid-edge node projections. The smart option allows for projections only if element quality does not degrade below a quality threshold. This version provides a new tet quality parameter and threshold parameter.

set node constraint [on|off|smart][tet quality [distortion|normalized inradius]] [threshold <value=0.15>]

With the introduction of the normalized inradius metric in this release, the tet quality setting can use this new metric as criteria for projecting mid-edge nodes. The new threshold value permits setting of a value at which mid-edge nodes will be straightened if the quality falls below. The node constraint options can also be set in the Options or Preferences dialog under Mesh Defaults and can be saved between Cubit runs. Parallel Tetrahedral Meshing

With this release, users have access to MeshGem’s parallel tet mesher, TetraHPC. Parallel tet meshing is an option in the Tet Mesh Command panel mentioned above. Parallel tet meshing is threaded and will support up to 8 concurrent threads. Geometry Reduce Command

The reduce command prepares a bolt for analysis by quickly breaking down its geometry into its simplest form and applying boundary conditions. The different options allow the bolt to be simplified, decomposed into its component parts, overlap removed and fitted to surrounding geometry, imprinted and merged with surrounding geometry, meshed with a qtri scheme on the plug volume, and more. The full command syntax for the command is:

reduce {volume<ids>} [fit_volume] [webcut [{head|shank|both}]] [imprint] [merge][qtri] [increment_block_ids] [summary] [diameter <value>] [group_id{<value>|default}] [group_name {<string>|default}] [head_block_id{<value>|default}] [head_block_name {<string>|default}] [shank_block_id{<value>|default}][shank_block_name {|default}] [plug_block_id{<value>|default}] [plug_block_name {<string>|default}] [bolt_block_id{<value>|default}] [bolt_block_name {<string>|default}]


Figure 8:


Figure 9: Groups Persist across Webcut

When a volume or body of a group is split in a webcut operation, the resultant pieces of the webcut will also be in the group. Sculpt HTET Unstructured Option

Sculpt now provides an option for splitting hexes into tets using an unstructured method where each hex is subdivided into six tets. Previously only the structured approach was available which split each hex into 24 tets. Thicken Void

A new option for ensuring physical separation between elements of different material blocks is now provided. The new thicken_void option will insert elements designated as the void block material where non-void blocks would otherwise be in contact. Better Fitting STL

Using the capture=5 option in Sculpt, mesh is fitted to the input STL. Sculpt now associates the grid edges of the reference mesh to the STL curve geometry. This is an extra level of association, in addition to the grid faces associated to the STL surface geometry. The result is better conforming of the mesh to the STL. Color Smoothing Improvement

Color smoothing (spot optimization) in sculpt now extends smoothing out one additional layer of nodes after the first smoothing iteration, ensuring better quality. Graphics, Utilities, etc. Enhancements to Free Entity Selection

The ability to select free surfaces (sheet bodies) has been added to the command:

select free [surface <id_list>] [curve <id_list>] [vertex <id_list>] [add|remove] No More Highlight Color Collisions

The automatic colors that Cubit assigns to entities have been slightly changed to avoid colors that are too close to the highlight color, which previously made it difficult to see what was highlighted. Case Insensitive Names

When naming entities in Cubit, names are now case insensitive. New HDF5 file type supported


Figure 10:

A new file type for saving the state of the Cubit model has been introduced in Cubit 2020.2. The new file type is .cub5.

The contents and structure of the new type is exactly the same as a .trelis file, but the extension name has been changed.

Beginning with Cubit 2020.2, users will be able to read in .trelis files, .cub5 files, and .cub files.

Users will be able to export .cub files and .cub5 files, but will not be able to export .trelis files. Over time, Coreform Cubit will deprecate support for .trelis files in favor of supporting only .cub and .cub5 files.

What are the motivations for this change? Defects Fixed in Coreform Cubit 2020.2

Ref #





Draw curve all produces error on composited surface



Extended selection *.py files not showing up on Mac



Spurious warning on cub import



Cubit slow to select with a long command string



Draw command outputs commands when nothing to draw



Dark mode on mac - model tree font matches the background color



Model tree needs refresh event after import



Crash - on merge all



Draw vol not is_meshed produces ERROR if everything is meshed



Nastran Export Issue



Selecting free vertex, curves and surfaces with is_free



Crash in RelWithDebInfo mode on Windows



SAW client has flashing graphics on Windows



Case sensitivity not respected in new parser help strings



MGT Function



Unique_genesis_ids not working with import ’filename.cub’



Change to fire ray output



Have an explicit option to name a new group



Bug with list geometry after volume regularization



Old attributes remain when importing cub file



Update get_total_bound_box documentation



Node moving (smoothing) bug in Cubit 15.6



Bug with selecting entities in Cubit 15.6



group_names_ids() missing from documentation



Crash - get_sub_elements



Nastran exporter broken since 15.4



Segfault in Cubit python module when importing an exodus database



Extraneous Command Output for volume copying



Add query for material types for all blocks in a Cubit session



Update netcdf



Selection not recognised in batch mode



Python 3.7 with Cubit-alpha - error loading shared object



Draw command outputs commands when nothing to draw



Equivolume and equiangle unrecognized



Documentation update - Mesh Refinement



Bug in splitting surface using close_to



Typo when trying to export quality metric from a lite mesh



Crash - tetmeshing with MeshGems 2.11



Performance issue with recent merge of parser changes



Misplacement of higher-order mid-face nodes during smoothing



Avoid generation of a new volume in surface removal on multiple shell volume



simplify command respects vertices now. Not respected previously



Hardlines can now be parsed with num_parents=1 Other Enhancements to Coreform Cubit 2020.2

Ref #





Cannot have return carriages within for loops in a Cubit python script



Keep volume in group after a webcut and reflections



Exodus-based surface mesh sizing by function



Select surface based on angle



Sierra mesh_scale to use more updated version of Cubit



Update Cubit component snap shot in Sierra repository



Create standalone Sculpt CMake for Alegra



STL import performance improvement



Import Mesh-basd geometry performance improvement on models with large sidesets



Enhanced meshing of composites. Better underlying faceting from ACIS



Improved robustness in blunt tangency command



topology check coincident node works off absolute distance instead of distance between bounding boxes



Fix for inability to create group in quality command using node distance metric



Allowing blocks to persist through unite operation with include_mesh option



Support Dark Mode



Add a command panel navigation method that minimizes wasted vertical space Limitations Introduced in Coreform Cubit 2020.2

Ref #





Superelement export not supported



Cubit is not supported on RHEL6 machines

1.3 Release Notes: Coreform Cubit 2021.11

1.3.1 Usplines

U-splines are a revolutionary new spline technology, developed by Coreform, and can be thought of as a generalization of B-splines, NURBS, and T-splines. A U-spline is created by first generating a linear mesh to define the spline’s topology, then prescribing the polynomial degrees of the elements and degree of smoothness with their neighboring elements, and then computing the resulting U-spline in Coreform Cubit. The generated U-spline can then be used as a watertight CAD geometry definition or as an accurate and computationally efficient mesh for a simulation, a technique known as Isogeometric Analysis (IGA).

1.3.2 Usplines: Initial support in ANSYS LS-Dyna

Bézier Extraction is an IGA/spline technology that transforms a spline into a traditional "element point of view" format that can be more readily implemented in traditional finite element codes. ANSYS LS-Dyna supports Bézier extraction via DYNA’s *IGA_INCLUDE_BEZIER keyword and the "BEXT" files that Coreform Cubit can export from a U-spline.

1.3.3 Geometry Compliant Lattice Structures

Geometry Compliant Lattice Structures (GCLS) is a novel lattice construction technology that enables the efficient design of lattices that conform to a CAD model’s shape and size. GCLS structures are built using a background U-spline mesh, which the user generates on a CAD volume of the lattice region. Several default lattice unit cells are provided, as is a workflow for designing custom unit cells. This new feature is available as a separate license, Coreform Lattice GC™ . Contact sales@coreform.com for a free trial or other inquiries.

1.3.4 Updates to Coreform Cubit Learn licensing

We at Coreform are committed to ensuring that students, hobbyists, and open-source simulation developers have access to the world-class mesh generation capabilities in Coreform Cubit. In the 2020.2 release we accomplished this by releasing the Learn license for Coreform Cubit. Beginning with Coreform Cubit 2021.11, we have streamlined the licensing process for Coreform Cubit Learn. Going forward, all Cubit Learn licenses will require internet access and an account at www.coreform.com to be activated. All legacy Coreform Cubit Learn licenses that used the RLM server will expire 60 days following the release of Coreform Cubit 2021.11 (approximately January 2022).

All Coreform Cubit Learn users are invited to obtain a new Coreform Cubit Learn license by following this process:
  1. Get the new Coreform Cubit Learn license
    • Login to your Coreform account

    • Go to “Request Free Coreform Cubit Learn License” page

    • Click “Get Coreform Cubit Learn” button

  2. Download the latest version of Coreform Cubit
    • Go to Coreform Cubit Downloads page

    • Download the most recent release of Coreform Cubit for your platform

  3. Activate new Coreform Cubit Learn license
    • Launch latest version of Coreform Cubit

    • In the activation window that appears, select “Educational” and enter the email and password associated with your Coreform account

1.3.5 Changing tool for generating documentation

For many years Cubit’s help has been generated using RoboHelp. We’re transferring to using Scribble as our documentation tool, which is based on the Racket programming language. This transfer of documentation tooling, while still in its infancy, is now "live" and this manual is rendered using this new tooling. We expect there to be some rough edges, so if you find any issues with the documentation please send us a bug report at support@coreform.com!

1.3.6 Geometry tools: Taper surfaces

Exposed ACIS "taper" operation that tapers an array of faces about an array of corresponding edges and a supplied draft direction by a given draft angle.

1.3.7 Geometry tools: Create tangent curve

Added a new curve construction method that creates a spline curve that connects two points with prescribed tangent direction at each point. This can be particularly useful for smoothly connecting two discontinuous curves.

1.3.8 Mesh export: ’mesh-only’ export for ANSYS LS-Dyna

A new option has been added to the LS-DYNA .k mesh export utility to enable only writing the mesh data, which can then be *INCLUDE-d into another LS-DYNA .k file. Previously, this exporter would output a minimum working input file that included "dummy" keywords for items such as materials, steps, etc.

1.3.9 User experience: Improved performance importing complex assemblies

Improvements to file-reading algorithms have resulted in dramatically (>10x) faster performance when importing certain STEP files. For example the wall time required to read a large test file has been reduced from ~720 seconds to ~20 seconds, matching the performance of another, industry-leading, CAD software. The specific change is a refactor of the algorithm that checks for clashing entity names, turning an algorithm into an algorithm. This is not a breaking change.

1.3.10 New features in Coreform Cubit 2021.11






Officially release U-splines



Officially release Coreform Lattice GC



Allow Coreform Cubit Learn users to log in with credentials



Implement uspline saves to HDF5



Use symmetric tessellation for GCLS default unit cells



Adds a GCLS implementation that uses the symmetric tessellation



Add methods to unfold a symmetric tessellation from a repeating unit



Add ’mesh_only’ option to LS-DYNA export



Add routine to make all basis funcs C0 across an edge



Add capability to output BEXT from cubit that is compatible with Dyna



Add command to fold lattice reference cell geometry in cubit



Added nodesets for 1d domains to the list of subdomain_dynamic_cells created by the build uspline command in cubit



Added command to taper a surface or surfaces at a given angle.



Added a breadcrumbs panel option to use small or large icons.



Auto change the working directory for the GUI on Windows if started in an unwritable location.

1.3.11 Defects FIXED in Coreform Cubit 2021.11






Progress bar bug in import healing.



Bug in the pick widget menu setup.



Bug in detecting entities added to another block.



Bug in the handling of triple quoted strings in Python.



Bug in the tree’s context menu when a pick widget was active.



Found some duplicate tree item issues.



Duplicate nodes in the navigation xml.



Location and Direction syntax errors not printed



Error in the GUI and a bug in direction parsing.



Impetus exporter not handling merged surfaces



Importing some STEP files is slow



Missing axis keyword in GUI panel



Tetmesh adaptivity memory management changed



Bad GUI keyword in volume cleanup



Missing keyword to GUI panel