CFD Utilities Files

JOIN_GRID Description:

   Utility for joining or rearranging multiblock grid blocks.

   This version assumes block faces match neighboring faces exactly.
   (Use the SPLIT_GRID program first if this is not true.)

   Blocks are joined in one, two, or three directions at once,
   first in the i direction, then j, then k (although the ijk
   convention within each input block can be permuted, and each
   direction can be reversed, via +/-1, 2, 3 input controls).

   The first block entered for a given joined block corresponds
   to the (1,1,1) element of a 3-D array of blocks being joined.
   The relative positions of further blocks follow the Fortran
   convention of varying the left-most index first, etc.

   Multiple joined blocks may be produced in one run.

   Reordering input blocks or simply transmitting them is achieved
   by entering 1 1 1 for the i/j/kjoin counts.

Sample control file (join.inp):

   Block joining control inputs:
   Number of blocks after joining
      2
   -----------------------------------------------
   Joined block ID
      1
   ijoin jjoin kjoin (# joins)
      3     2     2
   nblock(1:ijoin,1:jjoin,1:kjoin) & permuting indices
      37          1  2  3  ! Base block
      38          3 -2 -1  ! 1st block joined in i direction
      30          1  2  3  ! Block (3,1,1)
      40          1  2  3  ! (1,2,1)
      41          1  2  3  ! (2,2,1)
      50          1  2  3  ! (3,2,1)
      51          1  2  3  ! (1,1,2)
      60          1  2  3  ! (2,1,2)
      :           :  :  :
      99          1  2  3  ! (3,2,2)
   -----------------------------------------------
   Joined block ID
      2
   ijoin jjoin kjoin (# joins)
      1     1     1
   Input block
     101          1  2  3  ! Transcribe this block
   -----------------------------------------------

History:

   ??/??/??  James Reuther   Original split_xyz.
   11/12/99  David Saunders  Overhauled for use by mere mortals;
                             no attempt to handle other than PLOT3D
                             unformatted files; x(1:3,i,j,k) ordering
                             in memory is inefficient.
   11/16/99    "      "      Abandoned obscure original control scheme.
                             Functionality (probably different from the
                             original, however that worked) is spelled
                             out above.  Avoid unnecessary rewinds.

Origin:  NASA Ames Research Center, Moffett Field, CA