README.DLR_grids.extracoarse
============================

These meshes were generated with Centaur v8.1.3 including a patch to couple anisotropy to boundary groups. 
DLR was not able to generate a "Fine" or "Extra Fine" grid using Centaur. The files are named: 

File Types Provided:
1. trap_wing.dlr.centaur.extra_coarse.cgns
       see www.cgns.org
       Note that in this original file, the ZoneBC_t element lists are numbered incorrectly:
       the boundary element numbers start at 1, but they should be offset by the number of
       volume elements.

2. trap_wing.dlr.centaur.fixed.extra_coarse.cgns
       see www.cgns.org
       Corrected version of 1. Also renumbers, reorganizes, and divides both ZoneBC_t and Elements_t nodes 
       according to their shape (TRI_3 or QUAD_4) as well as their BC type. However, the slat, flap,
       wing, and body elements are no longer listed separately.
       (file conversion by C. Rumsey)

3. trap_wing.dlr.centaur.extra_coarse.netcdf
       For the NETCdf files please use a reader compiled with NETCdf v3.6 or newer.

4. trap_wing.dlr.centaur.fixed.extra_coarse.b8.ugrid
       AFLR3 file (unformatted, big-endian)
       (see: http://www.simcenter.msstate.edu/docs/solidmesh/ugridformat.html)
           write(2) nnodesg, ntface, nqface, ntet, npyr, nprz, nhex
           write(2) (x(i),y(i),z(i),i=1,nnodesg),    &
                    ((if2nt(j,i),j=1,3),i=1,ntface), &
                    ((if2nq(j,i),j=1,4),i=1,nqface), &
                    (ifacetag(i),i=1,ntface+nqface), &
                    ((ic2nt(j,i),j=1,4),i=1,ntet),   &
                    ((ic2np(j,i),j=1,5),i=1,npyr),   &
                    ((ic2nz(j,i),j=1,6),i=1,nprz),   &
                    ((ic2nh(j,i),j=1,8),i=1,nhex)
       but contains no record marks (ACCESS="STREAM")
           nnodesg  = number of nodes
           ntface   = number of boundary triangles
           nqface   = number of boundary quads
           ntet     = number of volume TETRA_4 elements
           npyr     = number of volume PYRA_5 elements
           nprz     = number of volume PENTA_6 elements
           nhex     = number of volume HEXA_8 elements
           x,y,z    = grid coordinates
           if2nt    = face-to-node pointers for boundary triangles
           if2nq    = face-to-node pointers for boundary quads
           ifacetag = surface ID number for each boundary face (1, 2,... , number of BCs)
           ic2nt    = cell-to-node pointers for TETRA_4 elements
           ic2np    = cell-to-node pointers for PYRA_5 elements
           ic2nz    = cell-to-node pointers for PENTA_6 elements
           ic2nh    = cell-to-node pointers for HEXA_8 elements
   trap_wing.dlr.centaur.fixed.extra_coarse.mapbc
       BC file describing the boundary condition for each surface ID
       (in this file we are using: 6662=y-symmetry, 5000=farfield, 4000=body)
       (file conversion by C. Rumsey)


Note: large files have been gzipped

The griding guidelines were fullfilled as much as possible; the only difference is the given number 
of points which cannot be reached with unstructured meshes because of the lower anisotropy in span-wise
direction compared to structured meshes.


Here are some statistics for the meshes:

Coarse:
-------
no_of_elements ....................: 37418633
no_of_tetraeders ..................: 18103873
no_of_prisms ......................: 19288488
no_of_pyramids ....................: 26272
no_of_surfacetriangles ............: 687930
no_of_surfacequadrilaterals .......: 7264
no_of_surfaceelements .............: 695194
no_of_points ......................: 12923391

For further questions please contact Stefan.Melber@DLR.de or Ralf.Rudnik@DLR.de