PAB3D Interface



The PAB3D interface writes a control file and a grid file for the multiblocks PAB3D flow solver. The control file contains a list of terms describing the physical properties, block dimensions, topology, boundary conditions and control settings for the flow solver. The grid file is written in the PLOT3D multiblocks unformatted format with no iblank array.

Creating the PAB3D control file and grid file

The translator writes the PAB3D files using the structured domain files (domain.1 to domain.n), the boundary conditions file (boco), the topology file (topo_mulcad_out) and the PAB3D parameters file. To create the PAB3D files, select the translator "PAB3D" in the "Output" menu from the ICEM CFD/CAE Manager. After clicking "Write output" you can specify the following options for the PAB3D interface:

The interface generates the PAB3D files located in the Transfer Shell. You may open a shell window in this directory by selecting the menu items "Utility" and "Transfer Shell".

Defining boundary conditions for PAB3D

In MULCAD, the boundary conditions are defined on subfaces using the "Unspec. Bound. Cond." menu. For a mesh created with the HEXA-Mesher, use the "general bound. cond." menu of the DDN-Mesher Interface. For more details on how to define boundary conditions in MULCAD or in the DDN-Mesher Interface, please refer to the General Remarks section.

The boundary condition types must be assigned on the block faces, except for singular faces where they are assigned to edges. After selecting a face, assign the appropriate type by entering one of the PAB3D bctype number.

        MULCAD          DDN-Mesher
        ------          ----------
        1.FLAG           1.string1        Enter the word TYPE
        2.NR             3.integer        Enter PAB3D bctype number

If no boundary condition types are defined by the user, the translator assigns automatically a type zero (no-slip wall) to all external walls.

Unmatching interfaces

Regular block interfaces are automatically written in the control file. However, the translator in not yet set up to detect automatically unmatching interfaces. Unmatching interfaces occur when 2 blocks have faces which are geometrically adjacent but are not sharing any topological entities (no common subfaces or edges). In order to tell the translator which unmatching faces must be coupled, the user must tag each faces of such interfaces. Two faces with the same name tag will be written as a block interface in the PAB3D control file.

        MULCAD          DDN-Mesher
        ------          ----------
        1.FLAG           1.string1        Enter any character string
					  (5 characters maximum)