CUBIT™ 16.04 Release Notes

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Product Description

CUBIT™ is a full-featured software toolkit for robust generation of two- and three-dimensional finite element meshes (grids) and geometry preparation. Its main goal is to reduce the time to generate meshes, particularly large hex meshes of complicated, interlocking assemblies.

Product Highlights

Meshing: CUBIT™ is a solid-modeler based preprocessor that meshes volumes and surfaces for finite element analysis. Mesh generation algorithms include quadrilateral and triangular paving, 2D and 3D mapping, hex sweeping and multi-sweeping, tet meshing, and various special purpose primitives. CUBIT™ contains many algorithms for controlling and automating much of the meshing process, such as automatic scheme selection, interval matching, sweep grouping and sweep verification, and also includes state-of-the-art smoothing algorithms.

Geometry Preparation: One of CUBIT™’s strengths is its ability to import and mesh geometry from a variety of CAD packages. CUBIT™ currently integrates the ACIS and Catia geometry kernels directly within its code base, allowing direct manipulation of the native CAD geometry format within CUBIT™. This reduces the errors and anomalies so often associated with geometry translation. CGM (Common Geometry Module) also boasts a facet-based geometry kernel developed at Sandia that can be used for remeshing or editing old mesh files or models defined by triangle facets. In addition, CUBIT™ has developed a comprehensive virtual geometry capability that permits local composites and partitions to geometry without modifying the underlying native geometry representation. The user can choose to ignore, clean-up or add features to the model allowing greater flexibility to meshing algorithms to generate better quality elements.

CUBIT™ Environment: CUBIT™ has developed both a convenient command line interface with an extensive command language as well as a polished graphical user interface environment. The GUI is based upon the cross-platform standard Qt, which allows the same look and feel on all supported platforms. Also included is a graphical environment based upon the VTK graphics standard which has been optimized for display and manipulation of finite element data and geometry. Fast, interactive manipulation of the model is a tremendous advantage for models with thousands of parts or millions of elements.

For more information on CUBIT™, including licensing arrangements and terms see the CUBIT™ website.

New Features in CUBIT™ 16.04

Index of New Features

Meshing

Geometry

Miscellaneous

Meshing

New option in collapse tet command

The collapse tet command has a new option [Interior]. It forces the collapse to happen on the interior of the volume, instead of on the exterior tets.  It prevents the collapse command from modifying surface triangles. See documentation.

Collapse Tet <ids> [Interior][Altitude | Aspect Ratio | Aspect Ratio Gam| Distortion | Inradius | Jacobian | Normalized Inradius | Node Distance | SCALED JACOBIAN | Shape | Timestep]

New tet quality metric mean ratio added

The mean ratio quality metric has been added for tet4 and tet10 element types. As with aspect ratio, mean ratio is sensitive to elongation, measuring the deviation of a tetrahedral element from an equilateral tetrahedron through the root-mean-squared edge length. See documentation.

Quality { Tet | Volume | Group | Block } <id_range> [ GLOBAL | Individual ] { Algebraic | Allmetrics | Altitude | Aspect Ratio Bet | Aspect Ratio Gam | Condition No. | Distortion | Element Volume | Inradius | Jacobian | Mass Increase Ratio | Mean Ratio | Normalized Inradius | Node Distance | Relative Size | Scaled Jacobian | Shape | Shape and Size | Timestep | Traditional }

Syntax changes for set node constraint command

The syntax for the set node constraint command has been slightly modified to prevent user error. The options quality and threshold, which are only relevant to the smart option can now only be set when specify the smart option. See documentation.

Set Node Constraint [{on|off|smart [tet quality {NORMALIZED INRADIUS|distortion}] [threshold {<threshold=0.3>}]}]

Geometry

Import CAD models into SGM

SGM(Scalable Geometric Modeler) is a new addition to CUBIT as an alternative to the default ACIS geometric engine. Capabilities within CUBIT for interacting with geometry are limited when a model is imported into SGM. This is the first increment to support basic visualization and we have a roadmap to support other capabilities such as geometry modifications, mesh generation, and mesh-modification working on top of the SGM engine. We do not support mixing ACIS, Facet, and SGM engines.

Import sgm <filename> [restore_ids] [read_colors]

STEP export now writes out names

If users have assigned names to geometry entities in CUBIT, those names will be written into a STEP file upon export. Similarly, upon STEP import those names will be assigned to the entities.

Miscellaneous

CUBIT™’s Python interface enhancements

The function measure_between_entities can now support mesh entities in addition to geometry entities.

Defects Fixed in CUBIT™ 16.04

Ref #Description
MESH-639 Desired number of through-thickness tet elements with proximity layers
MESH-4529STEP import unsuccessful on Mac
MESH-5513Crash playing journal file
MESH-5877Paver creates different meshes on windows and linux
MESH-5888Graphics vs. Nographics mesh difference when running same journal file
MESH-5923Unable to paste commands into Cubit 15.9
MESH-5940SAW was crashing cubit_server by making an obviously wrong RPC call
MESH-5953Crash after mbg import and reset
MESH-5976Crash when creating surface from composite vertices
MESH-6268Crash when using the ‘x’ key in graphics window
MESH-6271Long STEP file import times in Cubit
MESH-6297Crash on Mac when clicking on icon
MESH-6454Crash saving cub file with lite mesh

*The defects listed above are only those user-reported issues deemed “critical” or “blocker”. For information on other known defects contact Roshan Quadros.

Documentation Updates

The CUBIT™ 16.04 online documentation may be found here. A PDF version is also available for download. The CUBIT™ GUI installation also includes the full user documentation included with the program. The user’s manual may be accessed from the Help menu.

CUBIT™ 16.04 Contents of Release

CUBIT™ Program: The installation package includes executables and libraries, packaged in tar.gz files for Linux machines. For Windows, the package is in a self-installing executable, and for Mac OS X a .dmg file is provided. Both a command line and GUI version of CUBIT™ are included with the installation package for all platforms.

Documentation: Linux, Windows and Mac versions include full online documentation.

Platforms Supported

CUBIT™ 16.04 supports the following Platforms:

  • Linux RedHat Enterprise 7 and 8
  • Windows 10
  • macOS 10.14+

Non-Sandia Users

CUBIT™ is freely available for United States government use. For more information on licensing CUBIT™, including academic, commercial, and all other use, go to our licensing page. For current CUBIT™ users, CUBIT™ 16.04 may be downloaded from the CUBIT™ download page.

Sandia Personnel Only

CUBIT™ 16.04 may be downloaded from the CUBIT™ download page.

Windows

Download a Windows installation file and double-click to install.

MAC OS X

Download a Mac OS X disk image file. After the disk image is opened, click and drag the CUBIT™ folder to /Applications.

LINUX LANS

Check with your local LAN administrator for instructions on how to access CUBIT™ on your local LAN. In most cases typing one of the following commands at the UNIX prompt should allow you to execute CUBIT™.  In some cases, the full path will need to be specified:

/projects/cubit/<cubit_command>
cubitThe latest released version (16.04) of CUBIT™ deployed to the LAN.
cubit -noguiThe latest released version (16.04) with just the Command Line and graphics window
cubit -nogui -nographicsThe latest released version (16.04) with just the Command Line
cubit-16.04Version 16.04 with GUI
cubit-betaThe latest beta version still in development

Contact Information

CUBIT™ Help

For general technical questions including download, installation and CUBIT™ technical assistance.

cubit-help@sandia.gov

CUBIT™ Licensing and Passwords

Email: cubit-req@sandia.gov

CUBIT™ Support Lead

Trevor Hensley
Phone: 505-284-7756
Email: cubit-help@sandia.gov

CUBIT™ Project Lead

Roshan Quadros
Sandia National Laboratories
Computational Simulation Infrastructure (org. 1543)
Phone: 505-844-0408
Email: wrquadr@sandia.gov