AVS Modules                                                      read_F3D
copyright  1992,1993  Michael J. Rangitsch                    27 Oct 1993

NAME
      read_F3D  - read in an ascii FLOW3D data file from Harwell FLOW3D
                  version 3 (multiblock flow solver code)

SUMMARY
      Name        read_F3D

      Type        data

      Inputs      none

      Outputs     ucd (data at cells), geometry

      Parameters  NAME                 TYPE
                  Read F3D Browser     file browser
                  show blocks          boolean

DESCRIPTION
      This module reads an ascii formatted multiblock FLOW3D solution file 
      (from Harwell FLOW3D version 3) and stores the cfd data as a ucd 
      data set.  The dummy nodes stored at the edges of each computational 
      block are removed by the module.  The n-vector data at each 
      computational cell is stored as cell data, to use most of the ucd 
      modules, this must be converted to nodal data.  The cells of the
      ucd structure are all hexahedra.  

      Possible orientation (handedness) changes in the grid can defeat
      the interblock boundaries removal.  To fix this, use the AVS 5.0
      module 'ucd reverse cell' to correct the topology.  This module
      ensures that all cells have the same vertex ordering.

      Version 1.1 of read_F3D sets the minimum and maximum of the cell data
      values.  This is is required for some of the other ucd routines to
      work correctly.
     
      Version 2.0.1 of read_F3D modifies the treatment of data labels and
      adds units to the 'default' variables (u,v and w velocities, 
      pressure, volume fraction, k and epsilon (if stored)).  The
      cell indexing is improved (through a macro) and code is added
      to remove the internal block boundaries (this is the default.)
      Removal of the block boundaries gets rid of discontinuous 
      isosurfaces that existed in the earlier versions
 
      Version 2.1 of read_F3D corrects all of the block boundary removals.
      Each removal 'switch' has been tested at least once, and all are
      apparently correct.

      Version 3.0 of read_F3D adds a geometry output which displays all
      of the 2 dimensional patches in the FLOW3D data set as objects
      named the way the patches are named (all names converted to lower
      case).  The inter-block boundary patches are not shown.  This 
      code probably doesn't work for 3 dimensional patches.  The 
      geometries are under a single parent which allows easier 
      manipulation of the properties (like transparencies).

COMMENTS/QUESTIONS/SUGGESTIONS
     
     please send them to me at mrangitsch@dow.com

INPUT
      none

OUTPUT
      The output is a ucd data set with data stored at the cells and
      a geometry representing the structures given by the 2 dimensional 
      patches

PARAMETERS
      Read F3D Browser - a file browser to choose the FLOW3D dump file,
                         generally (xxx.dmp).  It must be an ASCII file.

      show blocks - a boolean parameter to show the block structure
                    (by not removing the interblock patches).  Showing
                    the blocks can result in discontinuous isosurfaces
                    and 'kinks' in streamlines.

EXAMPLE
      The following network shows a typical usage of read_F3D:


                              read_F3D
             ___________________| |
             |                    |
             |            ucd cell to node      generate colormap
             |                    |                     |
             |            ucd reverse cell              |
             |                    |                     |
             |      -----ucd extract scalars            |
             |      |                 |                 |
             |      |                 |   |-------------|
             |      |            ucd contour
             |      |                 |
             |      |     |-----------|
             |    ucd to geom
             |         |
              ---------|
                       |
             geometry viewer


RELATED MODULES
      read ucd, write ucd, read_flow3d

AVS Module						         read_F3D
Michael J. Rangitsch          				      27 Oct 1993