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Integrated CR( t)
=
∫
t
0
∫
FISSProduction( τ ) dτ
. (2.11-4)
t
FISSDepletion( τ ) dτ
0
Thus the user can calculate his own microscopic or macroscopic reaction rates and
their ratio by the option IBC5=1.
The defaulted definition of conversion ratio follows the description in the
burn-up chain library. As the initial setting, it is defined as the ratio of the
summation of capture reaction rates of Th-232 (if any in chain), U-234 (if any),
U-238 and Pu-240 to the summation of absorption reaction rates of U-233 (if any),
U-235, Pu-239 and Pu-241. (no decay effect)
IBC6
Option to write effective microscopic cross-sections into MICREF file
= 0 No cross-sections are written unless IXMICR (Sect.2.9) is not specified
to certain nuclides. This option is suggested if MICREF file is not
preserved.
= 1 Write cross-sections of the nuclides specified by Block-8
= 2 Write cross-sections of the whole depleting nuclides
= 3 Write cross-sections of the whole burnable resonant nuclides
Note:
In such a case that numbers of depleting materials, burn-up steps or depleting
nuclides are large as to cause shortage of core memory for virtual PDS file, keep
the requirement to write cross-sections to a minimum.
[cf.] Sect.1.4, Block-5 in Sect.2.2, Block-3 in Sect.2.9
IBC7
Option to make up collision probability table for PEACO calculation (effective if
IC5=±2 is specified in Sect.2.2)
= 0 Update at each burn-up step (suggested)
= 1 Make up tables at first two steps and use the second one after that
Note:
Option IBC7=1 is used to reduce large CPU time.
IBC8
Maximum length (LCHA) of decay chain in linear analysis
= 0 Defaulted value (LCHA=6) is used
> 0 Input value is used for LCHA. If large LCHA is used, as number of
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