REBUS 11.2892: Code System for Analysis of Fast Reactor Fuel Cycles.
Auxiliary Codes::
DIF3D 11.2892: Solves 1-D, 2-D, and 3-D finite-difference diffusion theory problems. VARIANT 11.2892: Solves VARIational Anisotropic Nodal Transport problems
Argonne National Laboratory, Argonne, Illinois.
Fortran 90 source code for Linux PCs, MacOSX and SUN, (C00822MNYCP02).
REBUS is a code designed for the analysis of fast reactor fuel cycles. Two basic types of analysis problems are solved: 1) the infinite-time, or equilibrium, conditions of a reactor operating under a fixed fuel management scheme, or 2) the explicit cycle-by-cycle, or non-equilibrium operation of a reactor under a specified periodic or non-periodic fuel management program. For the equilibrium type problems, the code uses specified external fuel supplies to load the reactor. Optionally, reprocessing may be included in the specification of the external fuel cycle and discharged fuel may be recycled back into the reactor. For non-equilibrium cases, the initial composition of the reactor core may be explicitly specified or the core may be loaded from external feeds and discharged fuel may be recycled back into the reactor as in equilibrium problems.
Four types of search procedures may be carried out in order to satisfy user-supplied constraints: 1) adjustment of the reactor burn cycle time to achieve a specified discharge burnup, 2) adjustment of the fresh fuel enrichment to achieve a specified multiplication constant at a specified point during the burn cycle, 3) adjustment of the control poison density to maintain a specified value of the multiplication constant throughout the reactor burn cycle, and 4) adjustment of the reactor burn cycle time to achieve a specified value of the multiplication constant at the end of the burn step.
REBUS will handle both equilibrium and non-equilibrium problems using a number of different core geometries including triangular and hexagonal mesh. The neutronics solution may be obtained using finite difference, nodal diffusion-theory and variational nodal transport methods. Fixed source depletion may be done with the three solution methods. Other features include: no restrictions on the number of neutron energy groups, and general external cycle with no restrictions on number of external feeds, reprocessing plants, etc. Fuel management is completely general for non-equilibrium problems. Microscopic cross sections are permitted to vary as a function of the atom density of various reference isotopes in the problem as appropriate for soft spectrum systems. The user may specify control rod positions at each time node in the problem. A number of relational database datasets containing various types of summary results are available for use in tailoring reports.
Related and Auxiliary Programs: DIF3D reads and writes the standard interface files specified by the Committee on Computer Code Coordination (CCCC). DIF3D is embedded into REBUS-3 and thus included in this distribution. Additional utilities are provided to allow users to better use the existing software package including a basic visualization capability called DIF3D_TO_VTK which generates input files for VISIT or Paraview. The FTU program is used to extract interface files from the STACK file REBUS generates during execution.
The total reactor burn cycle time is divided into one or more subintervals, the number of which is specified by the user. An explicit burnup is performed in each region of the reactor over each of these subintervals using the average reaction rates over the subinterval. These average reaction rates are based on fluxes obtained from an explicit 1-, 2-, or 3-dimensional diffusion theory neutronics solution computed at both the beginning and end of the subinterval. The transmutation equations are solved by the matrix-exponential technique. The isotopes to be considered in the burnup equations, as well as their transmutation reactions, are specified by the user.
All non - U.S. government funded license requests should be redirected to nera-software@anl.gov . Problem dimensions are all variable. Enough memory must be assigned to contain all the fuel cycle information and one-group system of the embedded neutronics package.
Most of the 24 test cases complete in a few seconds with a combined total time of 2 minutes for the benchmark suite where benchmark 20 and 22 take 35 seconds each with 21-23 accounting for a bulk of the total time. The existing coding only operates on a single core with no parallelism or threading noting that we are working towards using limited threading for DIF3D 12.0.
External data storage must be available for approximately 40 scratch and interface files. If insufficient memory resources are available then large random access scratch files may be created which are associated with the individual response matrices and vectors used for the solution. We strongly recommend mounting a separate hard drive as /tmp and running all jobs from that location to prevent network drive issues. The remaining binary files are sequential access files with formatted or unformatted record types.
No special requirements are made on the operating system. The included installation procedure requires a Fortran 90 (or newer) compiler and we impose compile-time fixed memory sizes (see installation README.txt). We note that the code was originally built to allow limited dynamic memory sizing (up to 2 GB) which was eliminated due to multi-platform issues. Although developed on the Cray and IBM 30xx, the current version is tailored for execution on Linux and MacOSX platforms.
At this point we have support for intel and gnu compilers noting that REBUS does not work with several older versions of intel and the gcc compiler 4.1.2.
B. J. Toppel, "The Fuel Cycle Analysis Capability REBUS-3," ANL-83-2 (March 1983 revised October 26, 1990) also included in PDF/REBUS-3_document.pdf.
R. P. Hosteny, "The ARC System Fuel Cycle Analysis Capability, REBUS-2," ANL-7721 (October 1978).
K. L. Derstine, DIF3D: A Code to Solve One-, Two-, and Three-Dimensional Finite-Difference Diffusion Theory Problems, ANL-82-64, Argonne National Laboratory, Argonne, IL (1984).
R. D. Lawrence, The DIF3D Nodal Neutronics Option for Two- and Three-Dimensional Diffusion Theory Calculations in Hexagonal Geometry, ANL-83-1, Argonne National Laboratory, Argonne, IL (1983).
G. Palmiotti, E. E. Lewis, and C. B. Carrico, VARIANT: VARIational Anisotropic Nodal Transport for Multidimensional Cartesian and Hexagonal Geometry Calculation, ANL-95/40, Argonne National Laboratory, Argonne, IL (October 1995).
C. H. Adams, et.al., The Utility Subroutine Package Used by Applied Physics Division Export Codes, ANL-83-3, Argonne National Laboratory, Argonne, IL (May 1992).
D. O’Dell, “Standard Interface Files and Procedures for Reactor Physics Codes, Version IV,” LA-6941-MS, Los Alamos Scientific Laboratory (September 1977).
Package consists of a Unix tar file which includes source code, code documentation (in pdf format), sample problem input and output, code dependent BCD and binary card image file descriptions, python scripts, a README installation file, an updated manual describing the revisions to the Variant option, and a series of documents highlighting the updates made to REBUS-3 since its release.
February 2014
KEYWORDS: DEPLETION; FUEL MANAGEMENT; BURNUP; CCCC INTERFACE FORMAT; DIFFUSION THEORY; TRANSPORT THEORY; CRITICALITY CALCULATIONS; REACTOR PHYSICS