1. Introduction to GAMBIT

2. Geometry And Mesh Building Intelligent Toolkit
What is GAMBIT?
Geometry And Mesh Building Intelligent Toolkit
A single, integrated preprocessor for CFD analysis:
Geometry construction and import using:
ACIS solid modeling capabilities
STEP, Parasolid, IGES etc. import (generally requires cleanup)
Mesh generation for all FLUENT solvers including FIDAP and POLYFLOW
Structured and unstructured hexahedral, tetrahedral, pyramid, and prisms.
Mesh quality examination
Boundary zone assignment
Mesh export

3. Problem Setup Geometry creation Meshing Examine mesh quality
GAMBIT modeling tools
Import from CAD/CAE or previously generated mesh file.
Clean up and/or decompose into meshable sections
Meshing
Local meshing – edge, boundary layers and size functions
Global meshing – face and/or volume
Examine mesh quality
Boundary and continuum zone assignment
Export the mesh to FLUENT

4. GAMBIT Startup
GAMBIT can be launched using the icon (Windows XP/2000 only).
GAMBIT can also be launched from a DOS command prompt or LINUX/UNIX prompt by typing the command
gambit sessionID
Gambit 2.3
Enter or browse for path to the working directory
Enter the session ID or select from previously stored sessions.
Startup options

5. GAMBIT Directory and Files
When GAMBIT starts up, it creates a directory called GAMBIT.#
# is a randomly assigned, four-digit process number
GAMBIT also creates a lock file, sessionID.lok, in the working directory
sessionID.lok prevents another user from starting up another session using the same ID in the same directory.
If GAMBIT crashes, this file must be removed manually.
Three files are created inside the GAMBIT.# directory.
The GAMBIT database. All geometry and mesh information is saved in this file. The database is often not retrievable after a crash.
sessionID.dbs
The journal file. All user instructions are stored in this file. The journal file is directly accessible from the Run Journal form.
jou
The transcript file. All output from the current GAMBIT session is stored here.
trn

6. GAMBIT Directory and Files
GAMBIT permanently saves these files to the working directory as sessionID.dbs, sessionID.jou, and sessionID.trn any time you issue the Save command (equivalent to any standard word processor).
The files sessionID.dbs, sessionID.jou, sessionID.trn are overwritten
New commands are appended to the journal file, sessionID.jou.
Upon successful exit of GAMBIT :
The GAMBIT.# directory is removed.
The lock file, sessionID.lok, is deleted.

7. The GAMBIT GUI Main Menu bar Operation Tool Pad Forms Area Transcript
Window
Global
Control
Description
Window
Command line

8. Operation Tool Pad Vertex Boundary Layer Boundary Types
Edge
Face
Volume
Group
Boundary Layer
Edge
Face
Volume
Groups
Boundary Types
Continuum Types
Coordinate Systems
Size Functions
G/Turbo
Geometry Cleanup
Plugin Tools

9. File Menu New, Open, Save, Save As and Exit Print Graphics
Prints graphics to printer or to file
PostScript, BMP, TIF, etc.
Run Journal / Clean Journal – Journal Utilities
Screen editor/command processor for journal files
Command processing:
Partial or global select/deselect
Automatic or stepwise journal file processing
Ability to load the current journal file
File browser
Clean Journal removes unnecessary entries, error commands, undo commands, etc. from the journal file.
View File – Opens a generic file viewer
View of the current output (the transcript file, ident.trn)
Ability to view other files as well

10. File Menu Import Export ACIS, Parasolid
IGES, STEP, Catia V4, Catia V5 (add-on)
ICEM Input, Vertex Data
CAD
Pro/E (STEP or DIRECT (add-on)
Optegra Visualizer
I-DEAS FTL
Mesh - mesh and faceted geometry files.
Export
IGES, STEP
Catia V4
Mesh
Export the mesh for your solver.
Export 2D mesh option guarantees 2D mesh

11. Edit Menu Title File – Ability to launch an editor within GAMBIT
Title will be included on any printed graphics
File – Ability to launch an editor within GAMBIT
Parameters – Ability to define, modify and list parameters
Defaults
Modify a large range of environment variables that affect:
User environment
Meshing characteristics
Geometry manipulation
Ability to load, modify and save a new set of defaults in $HOME/GAMBIT.ini which is loaded automatically at startup.
Undo/Redo
Ten levels of undo/redo (default)
Reducing number of levels also reduces memory requirements.

12. Solver Menu
The Solver selection will have an impact on the following input forms:
Available meshing algorithms
Available element types
Continuum types
Boundary types
Export mesh file
Default solver is FLUENT 5/6

13. Graphical User Interface
Transcript Window
Output from GAMBIT is printed here as well as in ident.trn. The transcript window can be expanded using the arrow button in the top right corner.
Description Window
Gives a short description of all global function buttons and screen areas
Command Line
Input of (non-GUI) commands
reset: deletes all mesh and geometry
reset mesh: deletes mesh, keeps geometry

14. Global Control Scale to Fit Pivot anchor control Four Split Four View
Light source
Labeling
Annotation
Undo
Redo
Display Orientation
Journal View
Modify Label, Visibility, Render, Show/Hide mesh, Silhouette
Wireframe, Shaded, Hidden line
Color coding by Entity Type or Connectivity
Examine Mesh

15. Global Control – Display Attributes
Specify Display Attributes form
Modify the following attributes (defaults given)
Render Wireframe
Mesh Volume OFF
Silhouette All ON
Label All OFF
Visibility All ON
Two ways of picking entities
All All entities are picked (Default)
Pick Individual picking including use of pick lists

16. Global Control Render Model Modify Light/Label type Color Mode
Wireframe
Shaded
Hidden
Modify Light/Label type
Change light source orientation and properties
Additional information on the entity label
Insert arrows and text for graphic presentations
Color Mode
Color by entity
Color by connectivity
Undo/Redo
Examine Mesh
Display different element types by quality, plane cuts, etc.

17. Forms List Box (picking) Active (yellow) Inactive (white) Radio Button
(mutually exclusive)
Option Button
(activates a menu)
Text Box
(click to activate/edit)
Check Box
(non-mutually exclusive)
Command Buttons

18. Forms
Text box
Field for input of data, expressions, parameters
Forms with several text boxes
The order of input is not important
Use the tab key to go to the next text box
Left-Click on any text box to activate.
List box
The active list box is displayed in yellow
Left-Click to activate
Tells you the name of the most recently picked item
The item is also highlighted in red on the screen
All previously picked items are displayed in pink
Individual pick lists for each list box
Forms with several list boxes:
Depending on the task, the order of picking may be important
Use Shift + Right-Click to go to the next list box

19. Forms Pick Lists Open the Pick List by clicking on the arrow
The "Available" list is sorted in the order of picking
Pick List functionality:
Pick or unpick, Selected or All entities by highlight in left column and by clicking on the arrows
Highlighted "picked" entities will appear red on the screen
edge.32, edge.33
Non-highlighted “picked” entities will appear pink
edge.26, edge.28
Right-click in lists area provides additional options
Filter can be used to control which objects are picked.

20. Save view to journal file
Mouse Operations
Action
Left
Middle
Right
Drag
x/y Axis Rotation
Translate (pan)
Zoom / Z-axis Rotation
Shift + Click
Pick
Next
Accept / Next Picker
Double-Click
Previous View
Save view to journal file
Ctrl + Click
Drag zoom
Stretch Zoom
Click points to grid
You can toggle between picking with or without using the Shift key:
Press and hold the right mouse button and click the left button.
The cursor changes to an eye shape.
Now, Pick/Next/Accept do not require the Shift key.
The Rotate/Translate/Zoom actions require the Shift key.

21. Mouse Operations – Selecting Entities
Pick a single entity
Shift + Left-Click on the entity
To pick a face or volume, Shift + Left-Click on one of the bounding edges
Pick multiple entities
Multiple “single-entity” picks OR
Click and hold, drag diagonally to pick several items at the same time
Upward diagonal drag will pick everything fully enclosed in the box.
Downward diagonal drag will pick anything inside or touching the box.
The most recent pick is highlighted in red
Previously picked items are highlighted in pink
Picking One Face
Picking Five Faces
This face
is not picked

22. Mouse Operations – Selecting Entities
Shift + Middle-Click = Modify Pick
The middle mouse button will behave differently depending on the mouse location:
Same: Cycle to the next available object within picking tolerance
New: Replace last pick with new pick at new location
Bad: Shift + Middle-Click on nothing is equivalent to “deselect last pick”
Shift + Right-Click = Apply or go to the next list box

23. GAMBIT Journal Files Executable list of GAMBIT commands Uses:
Created automatically by GAMBIT from both the GUI and TUI.
Can be created and/or edited manually using a text editor.
Journal files are small – easy to transfer, , etc.
Uses:
Can be parameterized, comments can be added
Easy recovery from a power loss or crash
Edit existing commands to create new ones

24. Running GAMBIT Journal Files
Journal files can be processed in two ways:
Batch mode (Run)
All commands processed without interruption.
"read pause" command will force interrupt with resume option appearing.
Interactive mode (Edit/Run)
Includes text editor for easy modification
Mark lines in process field to activate for processing.
Editable text field.
Right click text field for more options.
Auto or Step through activated process lines.
File
Run Journal

25. Appendix

26. Global Control Scale-to-fit – zoom in/out to fill the screen
Orient Model – major axes , isometric and:
Reverse
Previous
Journal view
Select pivot point around which the model rotates, zooms
Body center
Mouse position
Model display attributes
Turn on/off visibility, label, silhouette, mesh and hidden line on all or selected geometric entities
Preset configuration of the graphics window
4-view and split
Options to return to any single view