JAEA-Data/Code 2007-004 - Welcome to Research Group for ...

any of zone material identification numbers is negative. See IDCS in Block-16.
= 0 Isotropic scattering
= 1 P 1 scattering
= L P L component (L=1~5)
Note:
The maximum order of scatter depends on the library selected (cf. Sect.8.2).
Normally in the fine-group calculation, the scattering cross-sections up to P 5 are
available for the material containing light water. (scattering matrices of order L>1
are prepared for limited light nuclides in the SRAC.)
In the few-group calculation, the P 1 calculation is available only when the P 1
cross-sections are prepared in the MACRO file as the result of collapsing of
fine-group P 1 cross-sections after an anisotropic transport calculation by ANISN or
TWOTRAN. Since the few-group cross-sections collapsed by the PIJ calculation
do not include any higher order cross-sections, only P 0 (transport corrected)
calculation is available.
3 ISN Order of angular quadrature (S N order)
Enter even integer (= 2/ 4/ 6/...../16..... ; S 2 / S 4 / S 6 /....... /S 16 )
If negative, quadrature coefficients are taken from the 11th logical device.
Otherwise (for ISN from 2 through 16) built-in constants are used.
4 IGM Number of energy groups (internally set)
5 IM Number of rebalance coarse mesh intervals in the i-direction.
IM=3 in the example of Fig.2.6-1.
Bottom
i (X/R/R)
Left
Material-1
Material-2
Right
Material-3
j (Y/Z/θ)
Top
Fine mesh
Coarse mesh
Fig.2.6-1 Cordinates in TWOTRAN
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