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

equation is applied to meshes, the accuracy of solution depends on mesh size. For typical geometrical
models, they are illustrated at the end of this section so that the user can understands the relation
among zone, region and mesh.
The terms ‘left’, ‘right’, ‘top’, ’bottom’, ‘front’ and ‘back’ are used to indicate boundary
surfaces (or directions) of three-dimensional space under consideration. Figure 2.8-1 shows them on
X-Y and X-Y-Z models, and they are applied to all other models by the correspondence in Table 2.8-1.
Note that the ‘top and bottom’ in CITATION is inverse positioning to that of TWOTRAN.
Left
Top
X
Right
Y
Top
Front
Bottom
Left
Right
X
Bottom
Back
Y
Z
Fig.2.8-1 Naming of boundary surfaces in CITATION
Block-1 Control integers, always required /3/
1 NM ±Number of zones
As a special case, the number NM dose not count the zone allocated to the
internal black absorber whose cross-sections are not defined. See NUAC17 in
Card-003-2 and XMIS2 in Card-003-4.
Negative value activates the entry of the linear perturbation theory calculation
specified by Block-4 through Block-8.
2 NXR Number of X-Regions to make homogenized flux and cross-sections in PDS files.
Enter 0 if it is not required.
3 ID Option to select diffusion coefficient (cf. IC17 in Sect. 2.2)
= ±1 Select D1 in the SRAC macroscopic format through the CITATION
routine
= ±2 Select D2
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