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

flux point grid defined during system optimization should be defined with respect
to the initial values of receiver dimensions. Then, as the receiver size is varied the
azimuthal location of the flux points for an external receiver remain unchanged.
The height of the flux points is given by
Hit
Height of flux point = (Initial location) -
H
where Hit is the current iterated receiver height. For example, if a flux point is
chosen as 3/4 of the way up the receiver on the NE side, it will remain in this
relative position as W and/or H is varied.
For cavity receivers, the locations of flux points on the heat absorbing surface
scale with W and the height of the heat absorbing surface based on RADMIN
and RADMAX as
where Wit is the current iterated width, and HCAVit is the height of the heat ab-
sorbing surface based on current values of THT, W, and RY. The surface normal
at the flux point is held constant.
Choosing the correct location of flux points for a cavity heat absorbing sur-
face is not straightforward because the vertical center of the receiver (ZFC=O) is
the vertical center of the aperture but not the vertical center of the heat absorb-
ing surface. The bottom of the heat absorbing surface is chosen by DELSOL to
intercept all possible images that pass through the aperture from the farthest he-
liostat in the field, as described in Section V.A-5. The top of the heat absorbing
surface is defined as described in Section II.E, depending on either the ratio of the
value H to the aperture height RY or on the methods of Section V.A-5. For ei-
ther case, the scaling methods described above work to keep the flux points in the
same relative location on the heat absorbing surface.
For cavity receivers, the peak flux will usually occur along the back centerline,
but not necessarily at the center of the height of the heat absorbing surface. The
user should test several points along the centerline of the back wall in order to
locate and properly design for the maximum flux.
For a single flat plate receiver, the flux points on the heat absorbing sur-
face are specified using IFLAUT=3 with POLF=RELV( l), AZMF=RAZM( l),
ZFC=O, XFC=-Wx sin(AZMF), and YFC=-Wx cos(AZMF), where W is the
“diameter” defined in namelist REC (or use IFLAUT=4 option). The spacing
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