A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...

grid of points on the DELSOL assumed heat absorbing surface (IFLAUT=4).
The grid of flux points for the first three options does not have to lie on the DEL-
SOL assumed heat absorbing surface unless desired, and also does not have to
correspond to the assumed height of the heat absorbing surface. Thus, the effect
of different internal cavity configurations on flux distribution can be examined by
specifying different flux surfaces, the noncooled surfaces of the interior of a cavity
can be checked for internal spillage, or the flux distribution of small sections of a
receiver can be examined in greater detail.
If IFLAUT=l, the points are generated on the outside of a cylinder with a di-
ameter of DIAMF (meters). The center of the vertical cylinder is XFC meters
to the east, YFC meters to the north, and ZFC meters up with respect to the
receiver center. There are NXFLX flux points around the circumference from a
minimum surface normal azimuth of FAZMIN degrees to a maximum of FAZ-
MAX degrees (see Figure 11-16). The north side of the cylinder has an azimuth
angle of BO0, the east is at 270°, and so on. There are NYFLX flux points on the
height of the flux surface from a minimum of FZMIN meters to a maximum of
FZMAX meters, relative to ZFC. This option is most useful for studying cylindri-
cal external receivers or for examining the flux distributions of individual tubes in
a receiver.
If IFLAUT=2, the flux points are on the inside of a hollow vertical cylinder.
All of the variables have the same meaning as above, except that since the sur-
face normals are on the inside of the cylinder the azimuth on the north side is 0’
(not 180°), and the east side azimuth is 90’ (not 270°), etc., as shown in Figure
11-16. This option is useful for generating flux maps for the interiors of cavity re-
ceivers. However, it must be remembered that the center of curvature of a cavity
heat absorbing area, as defined by DELSOL, is at the aperture, so that the cylin-
der defining the flux surface should be centered using the appropriate values of
XFC, YFC, and ZFC. Then, the diameter (DIAMF) of the cylinder defining the
flux surface should be based on the actual depth of the cavity, which may be dif-
ferent from half of the width W of the cavity structure, depending on the choice
of the parameter RWCAV(1).
If IFLAUT=3, the flux points are located on a plane. The outward surface
normal f on the side of the plane on which the flux is incident makes a polar angle
of POLF degrees with the vertical and an azimuthal angle of AZMF degrees
with respect to the south direction (these angles are defined in an analogous manner
to the angles of the fi, 3, E, and F vectors in Figure 11-2). A Cartesian coordinate
system (if, jf, I,) is constructed with = f, where 2?f is in the plane and
horizontal and jf is in the plane and pointing up when 6, is horizontal (Figure II-
17). The origin of this coordinate system is XFC meters to the east, YFC meters
to the north, and ZFC meters up with respect to the “center of the receiver” as
described above. There are NXFLX equally spaced values of the flux points along
the 2, axis from a minimum of FAZMIN meters to a maximum of FAZMAX meters.
Similarly, there are NYFLX equally spaced values of the flux points along
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