There may be some cases in which you will need to read multiple mesh files (subdomains) to form your computational domain.
The grid node locations need not be identical at the boundaries where two separate meshes meet. FLUENT can handle non-conformal grid interfaces. See Section 6.4 for details about non-conformal grid boundaries.
There are two ways for reading multiple grid files in FLUENT:
Using FLUENT's Ability to Read Multiple Mesh Files
FLUENT allows you to handle more than one mesh at a time within the same solver settings. This multigrid handling capability is time saving, since you can directly read in the different mesh files in FLUENT itself without using other tools like TGrid or tmerge.
The steps to take when reading more than one mesh file are:
File Read Case...
In the Select File panel (see Section 2.1.2) (Figure 6.3.1), select the mesh file and click OK.
Grid Zone Append Case File...
In the Select File panel (see Section 2.1.2), select the second mesh file and click OK.
You will find that the second mesh is appended to the first.
FLUENT also allows you to append the data on the mesh. To do that, follow the procedure above. For the second step, use the following menu:
Grid Zone Append Case & Data Files...
Select the case file in the Select File panel (see Section 2.1.2) (Figure 6.3.1), and click OK. Both the case and data files will be appended.
| Reading multiple grid and data options are available only for serial cases, not for parallel cases.
Using TGrid or tmerge
| If one (or more) of the grids you wish to import is structured (e.g., a
FLUENT 4 grid file), first convert it to
FLUENT format using the
fl42seg filter described in Section
See the TGrid User's Guide for information about reading and writing files in TGrid.
utility tmerge -2d -cl -p my1.msh my2.msh final.msh
For a conformal mesh, if you do not want a boundary between the adjacent cell zones, use the Fuse Face Zones panel to fuse the overlapping boundaries (see Section 6.8.3). The matching faces will be moved to a new zone with a boundary type of interior. If all faces on either or both of the original zones have been moved to the new zone, the original zone(s) will be discarded.
| If you are planning to use sliding meshes, or if you have non-conformal boundaries between adjacent cell zones, do not combine the overlapping zones. Instead, change the type of the two overlapping zones to
interface (as described in Section
In this example, scaling, translation, or rotation is not requested. Hence you can simplify the inputs to the following: