Requirements Documentation

DOE-STD-3007-93

No unique requirements are applicable to this evaluation.

The calculations listed in this evaluation were performed using the CSAS25 module of the

SCALE4 package. The CSAS25 module contains three programs that were utilized, BONAMI-

II, NITAWL-II, and KENO V.a.2

BONAMI-II and NITAWL-II are cross section processing codes that are utilized to create

resonance corrected problem dependent cross sections for use in the KENO V.a program.

The system was modeled using the 3-dimensional neutron transport code KENO V.a, as

found in the SCALE4 package. KENO V.a is a Monte Carlo based computational method that

can be used in the determination of effective multiplication factors, keff, of various systems.

KENO V.a can utilize the problem dependent cross sections, as mentioned previously, in the

determination of keff. Various geometrical configurations can be modeled in KENO V.a.

The 27 group ENDF/B-IV cross section library, used for this evaluation, was collapsed

from the 218 group ENDF/B-IV library. This library contains 13 thermal energy groups (below

3ev) and 14 epithermal and fast groups (above 3 ev).

All calculations listed in this evaluation were performed on a Data General Avion Series

500 or Series 400 workstation operating under Data General Unix Version 5.4. The SCALE4

package was compiled using the Green Hills Fortran compiler, Version 1.8.5.

As part of the validation for this report a calculation was performed, using the above

described computer platform and code package, on an actual critical experiment performed in the

Borax V reactor.3 As outlined in "BORAX V Neutronics Report," (ANL-6964)3, an attempt to

2-13