Unstructured Tetrahedral Viscous Grid for the DLR-F4 Configuration (coarse grid for cell-based solvers) Geometry dimensions: Body length: 1192.0 mm Semispan: 585.7 Mean Aerodynamic Chord (MAC): 141.2 Wing Ref. area: 145400.0 mm^2 Outer boundary defined by a box (50 chord lengths away from geometry in each direction) Grid statistics: Boundary points: 23290 Surface triangles: 46576 Triangles on the no-slip surfaces: 30037 Total grid points: 470427 Points in the viscous layers: 389753 Tetrahedral cells: 2743386 Tetrahedrons in the viscous layers: 2208260 Total viscous layers: 35 (?) Complete viscous layers: 24 (?) Grid points across the T.E. thickness 5 Grid spacings: Chordwise grid spacing at L.E. ~0.450 mm Chordwise grid spacing at T.E. ~0.800 Maximum spanwise spacing at L.E. ~6.000 Maximum spanwise spacing at T.E. ~3.500 Grid spacing on the fuselage ~10.000 Grid spacing at the outer boundary ~5000.000 First layer spacing off the wall (d1) 0.003 Viscous grid distribution (stretching): Number of layers off the wall with constant spacing of d1 (zone 1) 4 Rate of geometric stretching outside zone 1 ~1.2 Grid files: name size (byte) 1) dlr_f4.mapbc 8241 2) dlr_f4.bc 1909692 3) dlr_f4.grd 32459505 4) dlr_f4.int 112478854 5) dlr_f4.poin1 6625827 Note: the grid files are compressed using "gzip" command. File description/format (all files are ASCII): 1) dlr_f4.mapbc: Patch/flow-boundary-condition file ---------------------------- c parameter(mpatch=***) c integer bcpch(mpatch) character*1 text(80) c open(13,file='dlr_f4.mapbc',form='formatted') c read(13,900)text read(13,900)text read(13,900)text read(13,900)text do ipatch=1,npatch read(13,*)jpatch,bcpch(ipatch),idum1,idum2,idum3 enddo c 900 format(80a1) c ---------------------------- where text = text line npatch = number of surface patches defining the geometry jpatch = surface patch index bcpch = flow boundary condition assigned to surface patch "jpatch" idum1,idum2,idum3 = dummy variables Note 1: you may want to define your own BC in bcpch(ipatch) in column 2. Note 2: patch family names are given as "Family" in this file: Family Description ------ ----------- fuselage fuselage box_lo lower side of the outer boundary box box_up upper side of the outer boundary box box_sym symmetry plane box_sd side of the outer boundary box opposite to the symmetry plane box_in in-flow side of the outer boundary box box_out out-flow side of the outer boundary box wing_uple upper surface of wing close to leading edge wing_lole lower surface of wing close to leading edge wing_up upper surface of the wing wing_lo lower surface of the wing wing_tip wing tip wing_te blunt trailing edge of the wing ********************************************************************** 2) dlr_f4.bc: patch/surface-triangle file ---------------------------- c parameter(mbf=***) c integer fapch(mbf),fnode(mbf,3) character*1 text(80) c open(unit=12,file='dlr_f4.bc',form='formatted') c read(12,*)nbf,nbc,npatch,igrid read(12,900)text do if=1,nbf read(12,*)jf,fapch(if),fnode(if,in),in=1,3) enddo 900 format(80a1) c ---------------------------- where nbf = number of boundary triangular faces nbc = number of surface grid nodes along patch boundaries (curves) npatch = number of surface patches igrid = 1 for inviscid grids; 2 for viscous grids text = text line jf = triangle index fapch(if) = surface patch index containing surface triangle "if" fnode(if,in) = node "in" of triangle "if" Note: triangle connectivities are according to the right-hand rule with the outward normals pointing into the computational domain. *********************************************************************** 3) dlr_f4.grd: x,y,z coordinates of the grid nodes ---------------------------- c parameter(mp=***) c real*8 crd(mp,3) c open(10,file='dlr_f4.grd',form='formatted') c read(10,*)nbn read(10,*)npo do ip=1,npo read(10,*)jp,(crd(ip,id),id=1,3) enddo c ---------------------------- where nbn = number of grid nodes on the boundaries (including nbc) npo = total number of grid nodes (including nbn) jp = node index crd = x, y, and z coordinates Note: the first "nbn" coordinates listed in this file are those of the boundary nodes. ************************************************************************ 4) dlr_f4.int: tetrahedral node connectivity ---------------------------- parameter(mc=***) c integer cnode(mc,4) c open(4,file='dlr_f4.int',form='formatted') c read(4,*)nc do ic=1,nc read(4,*)jc,(cnode(ic,in),in=1,4) enddo ---------------------------- where nc = number of tetrahedral cells jc = cell index cnode(ic,in) = node "in" of the tetrahedral cell "ic" Note: tetrahedral cell connectivities are given according to the right-hand rule (3 nodes of the base in the counter-clockwise direction followed by the 4th node.) ************************************************************************ 5) dlr_f4.poin1: field nodes in the B.L. linked to the surface mesh nodes -------------------------- parameter(mp=***) c integer lpoin(mp) c open(14,file='dlr_f4.poin1',form='formatted') c read(14,*)nbn,npv do ip=1,npv read(14,*)jp,lpoin(ip) enddo --------------------- where nbn = number of grid nodes on the boundaries npv = number of grid nodes inside the boundary layer (including nbn) jp = node index lpoin(ip) = surface node linked to the field node "ip" Note 1: "viscous" field nodes are generated along rays emanating from the surface mesh nodes. lpoin gives the corresponding surface node index for each viscous field node along the ray. Note 2: lpoin(ip) = ip, for ip=1,nbn (surface mesh nodes). ************************************************************************ For questions/problems, contact Shahyar Z. Pirzadeh Mail Stop 499 Configuration Aerodynamics Branch Building 1251, Rm. 102A 16 Victory Street NASA Langley Research Center Hampton, VA 23681-2199 Phone: (757) 864-2245 FAX: (757) 864-8469 E-mail: s.pirzadeh@larc.nasa.gov ************************************************************************