Download TrueGrid ® Tutorial Manual

I. Introduction to TrueGrid®
TrueGrid® is a general purpose tool for creating a multiple-block-structured mesh. Although the
beginning of this Tutorial provides some introductory information, the new user is strongly advised
to also read the first 2 chapters of the TrueGrid® User’s Manual, A User’s Guide and Reference
Manual.
The processes of creating a mesh and creating geometry are separated within TrueGrid®. Surfaces
and curves may be created internally, imported from a CAD/CAM system via an IGES file, or
imported as polygon surfaces using the vpsd command. A block mesh is then created and molded
to the shape of the geometry.
Making a mesh with TrueGrid® is analogous to sculpting: A block mesh is created using the block
command. Pieces of the block mesh are removed so that its topology matches that of the object to
be meshed. Portions of the mesh are moved, positioned along curves, projected to surfaces, etc.
Interpolation, smoothing, and zoning requirements are used to fine-tune the mesh. Parts created
separately are glued with the block boundary interfaces and common nodes merged together by
specifying a tolerance.
TrueGrid® is based on a powerful technique known as the projection method. The projection
method allows faces, edges, and nodes of the mesh to be directly placed on surfaces. Similarly,
edges and nodes of the mesh can be placed along curves. In this sense, TrueGrid® is a constraintbased mesh generator.
Additionally, if TrueGrid® is required to place two faces of the mesh sharing a common edge onto
two different surfaces, then it will automatically place the shared edge on the intersection of the two
surfaces. There is no need to construct the intersection curve of two surfaces; TrueGrid® will find
the intersection curve automatically. Likewise, a vertex required to be on three surfaces will be
placed at the intersection point of all three surfaces.
Other notable features of TrueGrid® include:
1. You can choose to run TrueGrid® in an interactive or batch mode or switch back and forth
between these two modes.
2. Any number of commands can be deactivated and reactivated.
3. The most frequently used mesh generation commands can be performed using the mouse.
4. The mesh can be easily refined.
5. TrueGrid® produces a session files that can be easily edited and rerun in a batch mode.
6. Every feature of the mesh can be made into a parametric feature.
There are a few conventions used in this tutorial. All text to be typed or produced by a dialogue are
placed in a Courier font. Keyword commands in a sentence are Bold face. The name of a button
in the menus or the environment window are Bold and Italic. It is also assumed that you are using
a mouse with 3 buttons. If you only have 2 buttons, use the right mouse button with the control key
down to simulate the third mouse button.
Copyright © 2005 by XYZ Scientific Applications, Inc.
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