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

The next set of cards is read at the start of the optimization calculation. At
this point in the calculation, the design will be affected by flux limits and aim
strategies. IAUTOP=l on the $REC$ card specifies the 1-dimensional smart aim-
ing option necessary for a flux limited external receiver design. In the $OPT$
namelist, tower height and receiver dimensions are varied over a range compatible
with the range of power levels. The variation in receiver height to width is speci-
fied to allow spreading of the flux along the height. IFLX=l in $NLFLUX$ turns
on the flux calculation, and the flux limit is set by FLXLIM. Since the maximum
flux should occur at the center of the north panel for the default design point,
only that one point is tested for flux levels. The default values in $NLFLUX$ will
result in the flux being calculated at the correct point and compared to the limit
FLXLIM.
The absence of storage is indicated by setting SMULT=1.0 in both $OPT$
and $NLEFF$. It is not necessary to set the reference costs to zero because the
code will calculate zero storage costs if no energy is available to charge storage.
The optimum systems for all power levels specified by the non-zero values of
IPLFL will be saved on a file on Unit 30 because the value of IOTAPE=l is spec-
ified.
- Comments on Output
The first part of the output consists of the printing of the performance
namelists, followed by summaries of the heliostat design and receiver used in the
initial performance calculation, zone by zone density and heliostat counts, an in-
solation table, and the zone by zone yearly average performance. A printing of
the optimization namelists follows, then a summary of the optimization variables
and design constraints. The default choice of IPROPT in $OPT$ produces the
abbreviated list indicating the combinations of optimization variables searched,
along with pertinent information related to each set considered.
The optimization results are then presented in a series of tables. Note in the
system design summary that all design variables fall within the ranges searched
except for the receiver height in the three smallest power sizes, which is at the
maximum allowed height to width ratio. Although energy costs would probably
not change significantly, a thorough user would want to rerun this case to allow
consideration of larger height to width ratios. Note also in the field layout sum-
mary that the field extends to RADMAX in all cases for a number of azimuthal
zones. The user could rerun this case with a larger value for RADMAX to allow
the code more flexibility in zone selection for field build-up.
In no case was the flux limit met for this series of calculations. It is likely
that a finer grid of choices for receiver dimensions and tower height would have
resulted in optimum systems in which the peak flux was much closer to the al-
lowed flux on the receiver. Sample Problem lb looks at the flux distribution over
the receiver for one of these systems in which the flux limit was not met.
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