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  Image says 'GridEx'.
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Table of Contents
Introduction
Software Execution
GUI Design & Operation
CAD & Geometry
Element Sizing
VGRID Sources
FELISA Sources
Visualization
Quick-Link Reference
FAQs

GridEx Tutorials
Geometric Primitives & Solid Operations
Generic Wing/Body - FELISA Sourcing
Generic Wing/Body - VGRID Sourcing
Feature Suppression & Regeneration
Parameter Modification & Regeneration
Transformations & Displacement

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Introduction

  GridEx is an interactive software system developed by Geometry Laboratory of the NASA Langley Research Center for the generation of unstructured meshes.  The software integrates native CAD geometry access, multiple unstructured meshing algorithms, and interactive 3D computer graphics through a Graphical User Interface (GUI) resulting in a package that is both powerful and easy to use.

  GridEx is part of the next generation of CFD modeling software being developed at the NASA Langley Research Center as part of the Fast Adaptive Aerospace Tools (FAAST) research project.  Foremost in its list of features is the seamless link established between geometry and mesh generation as the software supports a variety of native CAD formats.  The CAD data is transparently linked to the meshing operation through use of the CAPRI software interface.  GridEx exploits the topological information contained within models created by solid modeling CAD systems to drive the mesh generation process.  The result is a significant reduction in modeling time and effort over traditional methods which are typically based on the translation of geometric data to a common exchange format such as IGES.  Such translations most often result in a loss of the model topology and can lead to a host of other problems.

  GridEx also incorporates the FELISA VGRID surface and volume modules as well as the AFLR3 volume module for meshing flexibility.  Interactive controls permit the efficient specification of background sources, and unique capabilities provide the ability to assess source placements and relative strengths prior to volume mesh generation.  Advanced interrogation facilities employing "crinkle cuts" permit dynamic inspection of the resulting volume mesh while surface regions can be displayed with flooded contours based on grid quality metrics.

  This user's guide provides a comprehensive description of the capabilities provided within the GridEx software, their implementation, and instructions for their proper use.  Tutorials demonstrating the operation of the facilities are also provided to further illustrate the capabilities of the tool.  For experienced users, a quick-link summary is provided for rapid access to specific sections of the user's guide.

Crude movie demonstrating GridEx
Request GridEx software (US distribution only)

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Site Curator: William T. Jones
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Last Updated: Dec 11, 2001