CFD Utilities Files

MERGE_BLOCKS Description:

   [See also MERGE_BLOCKS_WITH HALOS in the same folder.]

   MERGE_BLOCKS is a utility for joining or rearranging multiblock grid
   blocks.  This adaptation of program JOIN_GRID allows for an optional
   function file.

   The input block faces are assumed to match neighboring faces exactly.
   (Use the SPLIT_GRID program first if this is not true.)

   Blocks are joined in 1, 2, or 3 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 (merge.inp):

   Block merging control inputs:
   Number of blocks after merging
      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, renamed JOIN_GRID here.
   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.
   10/24/06    "      "      MERGE_BLOCKS adapted from JOIN_GRID in order
                             to deal with optional function files too.

Origin:  NASA Ames Research Center, Moffett Field, CA.