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Grids - 2D Mixing Layer Validation Case

A series of 5 nested 2-D grids, in units of mm, are provided. As structured grids, these are comprised of 3 zones, connected in a one-to-one fashion. All grid files have been gzipped. Note that there are two different entry boundaries, one above and one below the plate. These two plate lengths are different in order to allow for different boundary layer thicknesses at the end of the plate; the thickness on the top of the plate is larger than the thickness on the bottom. Each coarser grid is exactly every-other-point of the next finer grid, ranging from the finest 737 x 737, 177 x 321, 241 x 321 to the coarsest 47 x 47, 12 x 21, 16 x 21 grid. The following figure shows a portion of the 185 x 185, 45 x 81, 61 x 81 grid (2 levels down from the finest grid). The part of the grid not shown extends to the right to x=1200 mm.
portion of Delville grid

Note: be sure to use double precision when reading the grids!

STRUCTURED VERSIONS OF GRIDS

PLOT3D Files

The structured PLOT3D grids are given in two different ways, as 2-D grids (x-y plane) or as 3-D grids (two identical x-z planes, separated by a distance y=1, giving one spanwise cell for all grid levels). You may use whichever is more convenient for your particular application.

Format for the structured 2D grids is PLOT3D-type, formatted, MG, 2D (nbl=3) - note that you must use double precision when reading! :

      read(2,*) nbl
      read(2,*) (idim(n),jdim(n),n=1,nbl)
      do n=1,nbl
        read(2,*) ((x(i,j,n),i=1,idim(n)),j=1,jdim(n)),
     +            ((y(i,j,n),i=1,idim(n)),j=1,jdim(n))
      enddo

Download the 2-D version of the grids in PLOT3D format here:

(2-D) 737x737, 177x321, 241x321 (gzipped) (5.8 MB)
(2-D) 369x369, 89x161, 121x161 (gzipped) (1.2 MB)
(2-D) 185x185, 45x81, 61x81 (gzipped) (< 1 MB)
(2-D) 93x93, 23x41, 31x41 (gzipped) (< 1 MB)
(2-D) 47x47, 12x21, 16x21 (gzipped) (< 1 MB)

Format for the structured 3D grid is PLOT3D-type, formatted, MG, 3D (nbl=3, and idim in this case is 2) - note that you must use double precision when reading! :

      read(2,*) nbl
      read(2,*) (idim(n),jdim(n),kdim(n),n=1,nbl)
      do n=1,nbl
        read(2,*) (((x(i,j,k,n),i=1,idim(n)),j=1,jdim(n)),k=1,kdim(n)),
     +            (((y(i,j,k,n),i=1,idim(n)),j=1,jdim(n)),k=1,kdim(n)),
     +            (((z(i,j,k,n),i=1,idim(n)),j=1,jdim(n)),k=1,kdim(n))
      enddo

Download the 3-D version of the grids in PLOT3D format here:

(3-D) 2x737x737, 2x177x321, 2x241x321 (gzipped) (11.8 MB)
(3-D) 2x369x369, 2x89x161, 2x121x161 (gzipped) (1.7 MB)
(3-D) 2x185x185, 2x45x81, 2x61x81 (gzipped) (< 1 MB)
(3-D) 2x93x93, 2x23x41, 2x31x41 (gzipped) (< 1 MB)
(3-D) 2x47x47, 2x12x21, 2x16x21 (gzipped) (< 1 MB)

If desired, example Neutral Map Files associated with 3-D version of the grids are given here (these files specify grid indices associated with each boundary condition - see The Neutral Map File):

CGNS Files

The structured grids are also available as CGNS files (3-D versions only, with two identical x-z planes, separated by a distance y=1, giving one spanwise cell for all grid levels). Note that the BCs written inside the CGNS files are for guidance only, and may not reflect the appropriate BCs needed for your application. To read/write CGNS files, (free) software may be necessary if your pre/post-processing tools do not already handle it. See: CGNS Website for details.

Download the 3-D version of the grids in CGNS format (gzipped) here:

(3-D) 2x737x737, 2x177x321, 2x241x321 (gzipped) (4.3 MB)
(3-D) 2x369x369, 2x89x161, 2x121x161 (gzipped) (1.1 MB)
(3-D) 2x185x185, 2x45x81, 2x61x81 (gzipped) (< 1 MB)
(3-D) 2x93x93, 2x23x41, 2x31x41 (gzipped) (< 1 MB)
(3-D) 2x47x47, 2x12x21, 2x16x21 (gzipped) (< 1 MB)

UNSTRUCTURED VERSIONS OF GRIDS

CGNS and AFLR3 Files

The unstructured versions of the same grids are all given as CGNS and AFLR3 (UGRID) files. Note that the BCs written inside these files are for guidance only, and may not reflect the appropriate BCs needed for your application. To read/write CGNS files, (free) software may be necessary if your pre/post-processing tools do not already handle it. See: CGNS Website for details.

The unstructured grids are all given as 3-D grids (two identical x-z planes, separated by a distance y=1, giving one spanwise cell for all grid levels). They are given here only as hexahedra (quadrilaterals in the x-z plane).

Download the unstructured CGNS grids (gzipped) as 3-D hexahedra (quadrilaterals in x-z plane) here:

Download the unstructured AFLR3 grids (gzipped) as 3-D hexahedra (quadrilaterals in x-z plane) here:

All AFLR3 grids have the same mapbc file: Delville_mmfinal4_quad_all.mapbc.

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Responsible NASA Official: Ethan Vogel
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Last Updated: 02/10/2025