RSIC CODE PACKAGE PSR-317





1. NAME AND TITLE

TRANSX 2.15: Code system to produce neutron, photon, and particle transport tables for discrete-ordinates and diffusion codes from cross sections in MATXS format.



AUXILIARY CODES

BBC 2.5: Converts MATXS libraries between formatted and binary modes, indexes libraries, and maintains libraries by inserting, deleting, and extracting individual materials.



UPD 1.2: Version-control program for TRANSX and BBC.

Three sample data libraries are included in this package to execute the TRANSX2 sample cases. They are MATXS10, (a complete 30 neutron group and 12 photon group library), an abbreviated version of MATXS11 (an 80x24 fast-reactor and fusion library), and an abbreviated version of MATXS12 (a 69 x 24 thermal library). DLC-177/MATXS11 is a complete library packaged by RSIC in February 1994. The complete MATXS12 is not yet available. MATXS10 was revised September 1994 and will replace RSIC's DLC-176/MATXS10 package. The versions of MATXS11 and MATXS12 in this package are unchanged from the original TRANXS2 release and trace back to 1992. The complete and revised (Feb. 1994) release of MATXS11 is available as DLC-177. The complete MATXS12 library is not yet available.



2. CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.



3. CODING LANGUAGE AND COMPUTER/OPERATING SYSTEM

Fortran-77, Cray/UNICOS, Sun/Unix, VAX/VMS, IBM RS/6000. (P00317/MFMWS/01)



4. NATURE OF PROBLEM SOLVED

TRANSX is a computer code that reads nuclear data from a library in MATXS format and produces transport tables compatible with many discrete-ordinates (SN) and diffusion codes. A new version of the MATXS format developed for NJOY91 requires the use of TRANSX2. MATXS libraries developed with NJOY89 must be processed by PSR-206/TRANSX-CTR. Tables can be produced for neutron, photon, charged-particle, or coupled transport. Options include adjoint tables, mixtures, homogeneous or heterogeneous self-shielding, group collapse, homogenization, thermal upscatter, prompt or steady-state fission, transport corrections, elastic removal corrections, and flexible response function edits.

There is a correction for BBC that fixes some problems with the use of directories. The BBC up7 file can be downloaded from the developer's web site: http://t2.lanl.gov/codes/transx/index.html.



5. METHOD OF SOLUTION

TRANSX reads through the materials in a MATXS library and accumulates the cross sections into a transport table using the user's mix instructions. At the same time, response function edit cross sections are accumulated using the user's edit instructions. They can thus be any linear combination of the cross sections available in the library. When the table is complete, it is written out in the desired format. Output options include DTF-style card images, FIDO, ISOTXS, and the binary group-ordered GOXS format.

Self-shielding is handled using the background cross section method. Heterogeneity options include homogeneous mixtures, escape using mean chord, lattices of cylinders by the Bell or Sauer approximations, and reflected or periodic slab cells by the Bell or E3 approximations.



6. RESTRICTIONS OR LIMITATIONS

Only narrow-resonance self-shielding is available in this version. This may affect accuracy for thermal problems.



7. TYPICAL RUNNING TIME

Running times on Cray XMP computers vary from a few seconds for typical 30-group problems to as much as 2 minutes for a complex 80-group problem with self-shielding and many regions.



8. COMPUTER HARDWARE REQUIREMENTS

TRANSX 2.15 has been tested on Cray, Sun, IBM RS/6000, and VAX computers. Earlier versions have been run on IBM mainframes. There are no reasons that it could not run on any machine (down to the 386 level). The executable code requires about 500 kB of memory. The sizes of MATXS libraries vary from 3 to 150 MB. Free disk space of 10 to 20 MB should be adequate if only 30-group problems are to be run. Problems using 80 groups or more may require 300 MB or more.



9. COMPUTER SOFTWARE REQUIREMENTS

Fortran-77 compiler and linker. TRANSX2.15 runs on Unix type operating systems and on Vax under VMS. RSIC installed TRANSX2.15 on IBM RS/6000 running AIX 3.2 with XL Fortran Version 2.3 and on a Sun Sparcstation 5 running Solaris 2.3 with F77 Version 2.0.



10. REFERENCES

R. E. MacFarlane, "User Input Instructions for TRANSX2.15," (November 1994).

R. E. MacFarlane, "TRANSX 2: A Code for Interfacing MATXS Cross-Section Libraries to Nuclear Transport Codes," LA-12312-MS (July 1992).

R. E. MacFarlane and D. C. George, "UPD: A Portable Version-Control Program," LA-12057-MS (1991).

R. E. MacFarlane, "TRANSX Today and Tomorrow," LA-UR, prepared for the OECD Seminar Workshop on NJOY-91 and THEMIS, NEA Data Bank, Saclay, France, April 7-8, 1992.



11. CONTENTS OF CODE PACKAGE

The package contains the referenced documents and source code for UPD, TRANSX, and BBC; machine-dependent update decks for CTSS, UNICOS, Sun, VMS, and IBM for both BBC and TRANSX; makefiles for Sun, IBM, and UNICOS systems; ASCII text versions of MATXS10, the abbreviated MATXS11, and the abbreviated MATXS12; input decks and output listings for 9 test problems; and a README file. TRANSX-2 is transmitted on tape cartridge in tar format.



12. DATE OF ABSTRACT

June 1992, February 1994, February 1995, December 1995.



KEYWORDS: MULTIGROUP CROSS SECTION PROCESSING; SELF SHIELDING; MATXS FORMAT; WORKSTATION