TrueGrid

MESHING
RESEARCH
CORNER

MESH/GRID
GENERATION
SOFTWARE
SURVEY

Contact: Matthew Koebbe, Ph.D.

Email: xyz@netcom.com

Web Site: http://www.truegrid.com/

Availability: Commercial Code, Stand-alone Mesh/Grid Generator

Stand-alone commercial product.  Though we provide completeoutput files for many of the most popular analysis packages, including ABAQUS, LS-DYNA, TOPAZ3D, MARC, ANSYS, etc.

Customer Support: Yes

Approximate Number of Users: 500

Pricing:

Platform: Windows, UNIX (SGI, HP, Sun, DEC, and IBM)

Input: IGES

We support the reading in of points, surfaces, and IGES files.  At this time, we do not import STEPP or SAT and have had no serious request or need for it.  Our IGES filter is the best in the industry since the projection method is tolerant of errors in the geometry. IGES is ideal for TrueGrid and all of the CAD systems that our customers use have an IGES option.
One of the more unique features in TrueGrid is the ability to import polygonal surfaces, which can be used in the same ways that other surfaces are used.  This includes automatic intersection with all other surfaces, the combining of surfaces, and elliptic smoothing. This ability is ideal for users with biological data which cannot be converted to analytical geometry or for geometry extracted from analysis to be remeshed.

Engineering Discipline: Structural, CFD, Thermal, Electro Magnetic

The gamut.  Just in the last 6 weeks, we have supported users withstructural, fluid dynamical, thermal, biomechanical, electro-magnetic and biomedical modeling needs.

Elements: Triangle, Quadrilateral, Tetrahedra, Hexahedra, Wedge (Prism)

Surface Meshing: Yes

Tri/Tet Method:

We focus on high-quality meshes and, therefore, concentrate ongenerating quadrilateral and hexahedral elements.  We do generate triangular, tetrahedral and wedge elements as sparingly as possible and only when the geometry demands it.

Quad/Hex Method: Grid Based, Structured Grid Generation

TrueGrid generates the highest quality hexahedral and quadrilateral block structured meshes, both in Cartesian and cylindrical coordinate systems.  When building multiple parts that do not
match, TrueGrid can automatically merge theparts together by building
an interface layer of all hexahedron elements.  This is not appropriate
for many fluids codes, but they work well with finite element codes.
TrueGrid has a new feature to take an existing mesh of a shell or solid structure such as a ship or a bone, and extrude the quadrilateral faces using hexahedron elements and extrude the triangular elements to form wedge elements.  The interesting point about this feature is the great control that the user has on the extrusion process to build a quality extrusion, including a fine, orthogonal mesh in the boundary regions.

Element Sizing Method: Manual

Like all other TrueGrid features, we provide as intelligent a defaultalgorithm as possible and then give the user complete control to over-ride this default in many ways.  We feel that the user best knows the needs of their analysis package, the importance of the various geometrical features that need to be captured by the mesh, etc.  We also offer a very complete list of diagnostics.  See our comments below.

Other Features: Boundary Layers, Adaptivity, Refinement, Mesh_Improvement

TrueGrid supports many types of boundary conditions:  constraints,initial conditions, sliding interfaces, joints, special elements, nodal, facial and elemental properties, as well as detailed material model generation.  The same methods are used to select parts of the mesh for different properties, so that only one method needs to be learned. These conditions can then be displayed graphically on the mesh.

Comments:

Since we claim to enable a user to produce a high-quality mesh,we provide a long list of diagnostic tools, including, though not limited to, orthogonality, aspect ratio, jacobian, and skewness. The user can visually display the worst elements and then modify the mesh to guarantee the highest quality in the most important regions. It should be noted that we support both interactive graphical development and batch file capabilities.