Authors: Stuart Rogers, Steve Nash, Pieter Buning
wkcut [-f infile] [-o outfile] [-jte j]
[-cutk1 x1,y1,z1] [-cutk2 x2,y2,z2]
[-dteabs da] [-dtechord dc]
[-relx rx] [-rely ry] [-relz rz]
[-swake dist] [-schord rc] [-xblend j]
[-[no]closegap] [-cap] [-hgrid] [-ibdir ib]
[-keepopen jclose] [-bluntclose]
-f infile: infile is the filename of the input surface c-grid.
This input file must be in the format of a PLOT3D single-zone
unformatted grid file.
Default: if no input filename is supplied, it will be prompted for.
-o outfile: outfile is the name of the output surface grid containing
the resulting c-grid with wake cut. This output file will be in the
format of a PLOT3D single-zone unformatted grid file.
Default: if no output filename is supplied, it will be prompted for.
-jte j: Specifies the index of the TE in the new grid; thus j-1 points
will be added for the wakecut on both the top leg and bottom
leg of the c-grid.
Default: j=25
-cutk1 x1, y1, z1:
-cutk2 x2, y2, z2: These specify the direction for the downstream end
of the wake-cut surface. The input components of the direction
vector will be normalized. The (x1,y1,z1) vector is used at the
k=1 end of the input surface, and the (x2,y2,z2) vector is used at the
k=kmax end of the surface; inbetween k=1 and k=kmax the direction
is interpolated. If only one of these is specified, this vector
will be used for all k.
Default: x1=1.0, y1=0.0, z1=0.0
-dteabs da:
-dtechord dc: Specifies the j-direction spacing of the wake-cut grid
at the trailing edge. By default, the local trailing-edge spacing of
the input grid is used. If you want to override this, use -dteabs
to specify the absolute spacing to be used for all k, or use -dtechord
to specify a fraction of the local chord. If both -dteabs and
-dtechord are input, -dtechord will override -dteabs.
Default: da=0.0, dc=0.0
-dendabs da:
-dendchord dc: Specifies the j-direction spacing of the wake-cut grid
at the downstream end. By default, the end spacing is a function
of the total distance, the trailing-edge spacing, and the number
of grid-points on the wake-cut surface; a geometric spacing with
a constant stretching ratio is used. If you want to override this,
use -dendabs to specify the absolute spacing to be used for all k,
or use -dendchord to specify a fraction of the local chord.
If both -dendabs and -dendchord are input, -dendchord will override
-dendabs.
Default: da=0.0, dc=0.0
-relx rx; -rely ry; -relz rz: The factors rx,ry,rz are used to multiply
the three-components of the trailing-edge-tangent vector which is
used to control the direction of the wake-cut surface at and near the
trailing-edge. For example, setting ry=0.0 can be used to force the
wake-cut surface to leave the trailing-edge of a tapered wing
within the local xz plane.
Default: rx=ry=rz=1.0
-swake dist: Specifes the length of the wakecut for all k-planes.
If set, this overrides the value of -schord.
Default: dist=0.0
-schord rc: Specifies a factor used to determine length of the
wakecut; rc is multiplied by the local chord to determine
the local wakecut distance. By default, this takes precedence
over the -swake parameter. However, if -swake is specified
with a non-zero distance, -swake overrides the value set by -schord.
Default: rc=0.6
-xblend1 xb1:
-xblend2 xb2: Specifes the fraction of the total wake-cut distance
where the transition from the TE tangent line to the final
cut-direction will take place, measured from the trailing-edge.
Specifying xblend<=0.0 will cause the final directional-vector
(cutk[12]) to be used for the entire wake-cut. Specifying
xblend>=1.0 will cause the local input-surface tangent to
be used for the entire wake-cut. xb1 is used at k=1, xb2 is
used at k=kmax, and inbetween they are interpolated.
Default: xb1=xb2=1.0
-noclosegap, -closegap: This controls whether or not the wake-cut
will be closed when the body has non-zero-thickness trailing-edge.
Default: -closegap
-cap: This flag indicates that the input surface grid should be treated
as a cap grid, and not a c-grid.
Default: false
-hgrid: This flag indicates that the input grid is an h-grid,
and that the wakecut should be added by extrapolating from
the grid face indicated by the input variable ibdir. This
option will work for a volume grid.
Default: false
-ibdir ib: This indicates which computational face the extrapolation will
grow from in the hgrid option. ib = -1,-2,-3,1,2,3 indicate the
j=1, k=1, l=1, j=jmax, k=kmax, and l=lmax faces, respectively.
Default: ib=1
-keepopen jclose: This controls how many cells will be used to close
the wake cut (jclose is how many cells aft of the TE to the first
periodic cell).
Default: jclose=1
-bluntclose: (Only applies when using the -keepopen option (see above))
This will change the way that the blunt TE is closed off to stay the
same thickness that is at the TE, and then sharply closes it at the
jclose cell. The default is to gradually close the blunt TE over
the cells leading to the jclose cell.
Default: false
NASA Ames Research Center, Moffett Field CA 94035-1000, (650) 604-5000
Privacy Statement
URL: http://rotorcraft.arc.nasa.gov/
This Website Maintained By: Randall L. Peterson.
Responsible NASA Official: Dr. William Warmbrodt (Chief)
Ames Research Center Homepage
NASA Homepage