SCALE-4.2 Available from RSIC

The modifications and enhancements included in Version 4.2 should substantially improve the portability of SCALE to all types of UNIX workstations. One master FORTRAN source that can be easily ported to Cray UNICOS, IBM MVS, or UNIX workstations is now maintained at ORNL under our quality assurance and configuration control guidelines. System-dependent routines for UNIX and MVS systems are similarly maintained.

Significant improvements in SCALE-4.2 are listed below. Most of these appeared in previous issues of the SCALE Newsletter, but are included here for completeness.

SAS4 Added an option to input axial source profiles for both radial and axial dose calculations. Also added an option to calculate point-detector estimates from collisions in both halves of the geometry for axial dose calculations.

ORIGEN-S, SAS2, COUPLE Modified programs to accept the new updated and expanded decay data and fission-product yield libraries (January 1993 Newsletter) and to use combined binary libraries that include multicycle cross sections.

ORIGEN-S LIBRARIES Replaced the six standard ORIGEN-S card image libraries with two new libraries, END6DEC and XSECTPHO. END6DEC contains the updated and expanded decay data library based on ENDF/B-VI data. XSECTPHO contains the basic cross-section and photon-spectra data and updated fission-product yield data based on ENDF/B-V data. In addition, the BASICLWR binary library has been replaced with a binary library that has updated cross sections from the ENDF/B-IV and -V 27BURNUPLIB for all nuclides in that library.

HEATING7, HTAS1, OCULAR Version 7.2 of HEATING, which operates on both UNIX and IBM/MVS operating systems, was added. HTAS1 and OCULAR were updated to run with this new version.

A program to convert the source files between IBM mainframe and workstations is included to facilitate code conversion. Language flags allow some of the source codes to compile on DEC/Ultrix and Cray/UNICOS systems. Suggestions are provided for Vax/VMS, Sun, HP, and ALPHA users. The files come configured for an IBM RS-6000 workstation.

SCALE-4.2 Minor Corrections

The following minor corrections were made to SCALE-4.1 to produce SCALE-4.2. Most of these have appeared in previous issues of the SCALE Newsletter, but are included here for completeness.

KENO V.a: Module was fixed to correctly calculate matrix keff by array number for a problem using a bare global array (i.e., there is no global unit).

KENO V.a: Corrections made for applying differential albedo boundary conditions to supergrouped problems where the global unit contains only an array specification. Note that this combination of options is rare. The effect of this error on keff is very large for this type of problem and will give physically unrealistic results.

CSAS and KENO V.a: Error checking during input processing was added so that these modules terminate with an error message if input errors are encountered.

MIPLIB: Corrected calculation of Dancoff correction factor for cylindrical and spherical lattice cells. ("See Words to the Wise..." below for more information.) Also corrected calculation of Dancoff factor for multiregion slab cell with vacuum boundary conditions to appropriately set the value to zero.

MIPLIB: Made a correction to accept an input Dancoff factor of zero and use it. Added a check to ensure that all Dancoff factors input are between zero and one.

MIPLIB: Corrected the dimensional consistency test for annular cells and asymmetric slab cells. This change allows correct problems that previously failed to run properly.

NITAWL-II: Parameter added to prevent exponent underflows for very dilute resonance calculations on workstation.

NITAWL-II: Corrected discrepancies in maximum fractional energy loss of neutron in admixed moderator calculation and Simpson rule calculation of collision density as documented in "Improved Calculation of Flux Shapes with the Resonance Shielding Code NITAWL," by J. Oppe, ECN-I--93-003. Slight effect on all calculations; impact will vary, but is insignificant for hydrogen-moderated systems.

MORSE and SAS4: (a) Fixed the option that allows the geometry media number to differ from the cross-section media number. Prior to this correction, MORSE did not select the proper cross- section media number when this option was selected. Previously run problems with geometry and cross- section media numbers that differ should be rerun with the new version. (b) Error recovery procedure was added so that when a fatal geometry error occurs, the results will be normalized and printed for n-1 batches, where n is the batch number in which the error occurred.

MORSE-SGC: Modifications made for compatibility with the new options in SAS4 (i.e., the axial source profile input option and the option for estimation to point detectors from collisions in both top and bottom halves of geometry).

Standard Composition Library: Updated resonance data flags for nuclides that have resonance data in ENDF/B-V.

XSDRNPM: Corrected calculation of number of direct access data blocks needed to weight the cross sections to prevent occasional failure. Improved calculation of balance tables.

SAS2: Corrected so that 'parm=check' would work on workstation.

27GROUP, 27BURNUP, and 218GROUP: These libraries have been updated to correct an error found in the chlorine cross sections.

BONAMI: Corrected so that a case with a number density of zero for a nuclide that has Bondarenko data will run without failing.

AIM: ft47ft001 is no longer required for AIM to execute on workstations.

All modules: The Program Verification Table, printed by Subroutine Library member LISTQA, was modified to print the correct version numbers for modules with version numbers of 10 or greater.

No KENO-V.a Training Class

Words to the Wise...

Don't Let Your Holes Touch in KENO-V.a Geometry

This restriction is stated in Sect. F11.4.4 of the SCALE documentation near Figures F11.4.2 and F11.4.3. It applies to all versions of KENO-V.a and has been in the documentation since the SCALE-4.0 release. The SCALE staff at ORNL are currently investigating a programming change to solve this problem. In the meantime, users should make sure there is a slight gap in the KENO-V.a geometry model between each hole and any adjacent region. The gap can be as small as 1 in the fifth significant digit.

This error has been corrected in SCALE-4.2 and SCALE-PC, as indicated on the previous page. All CSAS, SAS1, SAS2, SAS3, and SAS4 cases with cylindrical lattice cells will give slightly different results due to this correction. For consistency, the spherical case was modified to use the same variable as the cylindrical case, although the original variable had not been modified in this case. A second change that involved reducing the distance to the first untreated row by the diameter of the pin or sphere to get a surface-to-surface distance was not implemented after testing showed it to be overly conservative.

The adjusted input to circumvent the error in SAS2H would look like this:

SCALE-PC NEWS

Update of SCALE-PC Available Through RSIC

CSAS - Corrected the Dancoff correction factor calculation for cylindrical cells. The previous version gave nonconservative k values for small cylindrical cells (O.D. < 0.4 cm). (See Words to the Wise... for more information.) Also corrected the type of function E3 from single to double precision. This error caused some problems to fail with underflows or overflows. Corrected the Dancoff factor for a multiregion slab cell with vacuum boundaries to be set to zero. These errors were also in SCALE-4.1, but were corrected in SCALE-4.2.

KENO-V.a - Corrected the type of three variables from single to double precision that caused a problem with a very small number density (1E-20) to fail with an arithmetic overflow. Changed the default memory for a KENO-V.a stand-alone problem to 400,000 words. The default is 1,000,000 words in the mainframe/workstation version. Modified the program to write the keff by generation number to the PC screen as it is calculated so that the user can monitor the progress of the calculation.

All Modules - Relinked with new SUBLIB subroutine ALOCAT that dynamically allocates the requested memory for a module when it is called by the SCALE driver. Previous versions of SCALE-PC allocated 100,000 words of memory for all modules, regardless of the amount requested.