A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...
A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...
A User's Manual for DELSOL3 - prod.sandia.gov - Sandia National ...
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In other words, PLOST,R is the same at any time of the day or year. Implicit<br />
in the assumption is that the same temperature profile is maintained on the receiver<br />
at all times and <strong>for</strong> any receiver size by adjusting the fluid flow rate, and<br />
that convective losses vary insignificantly with time.<br />
Letting ~RC,R,DP be the design point efficiency dased on receiver radiation and<br />
convection losses, then:<br />
qRC,R,DP =<br />
Pth,R - PLOST,R<br />
Pth,R<br />
=I---- QRAR<br />
Pth,R<br />
(1II.G - 10)<br />
where Pth,R = gross thermal power absorbed by the receiver at the design point.<br />
Similarly, let ~RC,R,AVG be the yearly average efficiency as calculated by:<br />
~RC,R,AVG =<br />
ETOT,R - (HOP x PLOST,R)<br />
ETOT,R<br />
=I- HOP x ~RAR<br />
ETOT, R<br />
where ETOT,R = total gross energy absorbed by the receiver per year<br />
Hop = total number of hours of receiver (not plant) operation.<br />
(1II.G - 11)<br />
CYR is determined from some reference design <strong>for</strong> which the radiation and con-<br />
vection losses have been calculated in more detail. Rearranging Equation (II1.G-<br />
10) ,<br />
(1II.G - 12)<br />
where the variables have the same meaning as above and the O superscript refers<br />
to the reference. Current default values depend on the type of receiver, but in<br />
all cases flow is from the bottom to the top of the receiver, molten salt flow is<br />
assumed, and q&-.R should be calculated based on the average ambient conditions<br />
(wind speed, temperature, etc.).<br />
82<br />
Defaults <strong>for</strong> an external receiver (cylindrical or flat plate) are<br />
q&R (REFRC) zz 0.83<br />
P:h,R (REFTHP) = 4.10 X IO8 watts