Importing a grid from Gambit

You can import a mesh created in Gambit.

  1. You have to save your mesh as a Neutral file (mesh.neu) in gambit into your working directory.
  2. Start Prostar and type the command gambit ; then type the mesh filename mesh.neu. The grid is then imported.
  3. Replot all cells.
The downside is that the vertex numbering is not regular. Therefore the boundaries selection gets harder.
Creating a grid

In STAR-CD it is easy to create rectangular shapes and circular shapes.

Go to the Create and Import Grids > Create Grids > Create 3D Grids menu.

  1. Select a cell type: when you have difference parts in your mesh it is useful to define the corresponding fluid region with another color. Like in our case for the moving cells and the non moving cells.
  2. Select a coordinate system: Use this button to chose the type of coordinate system or to create a new one. Be careful to use the correct coordinate system when for exempla defining the boundaries.
  3. Create the mesh: type in the dimensions: starting point, end point and number of cells in each direction and click Generate grid



    Merging overlaying vertexes


When creating a circular shape the first and last series of vertexes are occupying the same positions. They must be merged to complete the mesh creation. You can use the VSET command to select the vertexes by defining a selection box.

VSET, LOPT1, LOPT2: Builds a vertex set. The set is used to define the range of plotted vertices. The set can also be used in lieu of any vertex range commands throughout the program.



For example:
VSET NEWS GRAN 0.1, 0.5, -0.001, 0.001,,,1
selects all the vertex within 0.1<x<0.5; -0.001<y<0.001, any z using the cartesian coordinate system 1.


Copy the file maillage.neu in your working directory.

In prostar type:
maillage (the name of your .neu file, the file is here)

Plot cells


Go to the Create and Import Grids > Create Grids > Create 3D Grids menu.

Create a new Coordinate system 4 with the setting:
Cylindrical, Xc=0,5, Yc=0,5.
New (global)
Set it active

Change the Cell type:
Choose 4 in the list
Set the color index to 6

Create the Mesh by typing the following setting:

Generate Mesh