1

Otto-von-Guericke-Univ. Magdeburg!

Computational Fluid Dynamics: Preprocessing!

April 16, 2012!

2

Introduction! GAMBIT is an integrated preprocessor program for CFD!

  geometry construction and import!  mesh generation with structured and unstructured elements!

  mesh quality examination!  definition of boundary zones!

3

File structure!  GAMBIT is an integrated preprocessor program for CFD!

  project.dbs is a database with all information!  project.jou is a text file with all commands!  project.trn is a text file with all output from Gambit!

  Temporary directory GAMBIT.# with the following files:!  project.dbs, jou und trn!

 project.lok in your working directory. It prevents any user from starting up another session using the same identifier in the same directory.!

4

Gambit - GUI!

5

„Transcript“ window!

6

„Transcript“ window!

Transcript window can be expanded using arrow button in top right corner.

Output from GAMBIT is printed here as well as in project.trn!

7

„Description“ window!

8

„Description“ window!

It gives a short description of all global function buttons and screen areas.

9

Menu structure!

10

Menu structure!File! Edit! Solver!

11

Import geometry!

in Menu File!

12

Operation!

13

Operation!

Geometry!

Mesh! Boundary conditions!

other Tools!

14

Creating geometry!Vertex!(point)!

Edge!(curve)!

Face!(surface)!

Volume!

15

Creating edge!Edge!

16

Creating face!

Face!

17

Creating volume!

Volume!

18

Boolean operations!

Face! Volume!

19

General operations: Move/Copy!Vertex! Edge!

Face! Volume!

20

General operations: Move/Copy!

21

Vertex! Edge!

Face! Volume!

General operations: Delete!

22

Edge meshing!

Edge mesh!

Possibilities!

23

Edge meshing!Temporary meshed edges !are white!

Single-sided grading!

Symmetric grading!

Asymmetric grading!

When you Apply, the!mesh nodes will turn blue!

24

Face meshing!

Face mesh!

25

Face meshing!

26

Face meshing!

27

Volume mesh!

Volume meshing!

28

Volume meshing!

29

Volume meshing!

30

Boundary conditions!

Definition of the !Boundary conditions!

Possibilities!

31

Definition of the Fluid zone!

Definition of the !Volume!

Possibilities!

32

Global Control!

33

Global Control!

Check mesh !quality!

Scale-to-Fit!

34

Examining the mesh!

35

Examining the mesh!

36

Examining the mesh!

37

Export mesh!Menu File!

38

Mouse operations!

Mouse! Movement! Description!Left mouse! All direction! Rotation!Middle mouse! All direction! Translation!Right mouse! Horizontal! Rotation (z-direction)!Right mouse! Vertical! Zoom!Ctrl- Left mouse! Diagonal! Drag zoom!Shift- Left mouse! Pick an object!Shift- Middle mouse!

Next / Change direction!

Shift- Right mouse! Accept / Next Picker!

39

End!

April 16, 2012!