1. NAME AND TITLE

PSU-LEOPARD/RBI 90.1: A Spectrum Dependent Non-Spatial Depletion Code.

2. CONTRIBUTOR

Ruder Boskovic Institute, Zagreb, Yugoslavia, through the NEA Data Bank, France.

3. CODING LANGUAGE AND COMPUTER

Fortran 77; IBM PC.

4. NATURE OF PROBLEM SOLVED

PSU-LEOPARD is based on the mainframe code LEOPARD, developed by Westinghouse (see CCC-343/LEOPARD) and later modified by Pennsylvania State University. PSU-LEOPARD is a spectrum dependent non-spatial depletion code. It differs from the standard LEOPARD code in two aspects: generation of tables with polynomial coefficients representing macroscopic cross sections in terms of depletion and boron concentration; and input simplifications for calculations of the Three Mile Island reactor (a subroutine was added to accommodate this type of reactor). RBI version 90.1 of PSU-LEOPARD includes a restart option, numerically more stable polynomial fit, PC timing routines, and a few other new options. Group constants are fitted by polynomials in burnup and in soluble boron concentration providing a complete set of data for automated core depletion.

5. METHOD OF SOLUTION

The fast neutron energy range is divided into 54 energy groups and the fast constants are calculated using B1 and Grueling-Goertzel approximations. The neutron thermal energy range is divided into 172 energy groups and the thermal constants are averaged over the Wigner-Wilkins spectrum.

6. RESTRICTIONS OR LIMITATIONS

The energy range is from 0 eV to 10 MeV with 0.625 eV cutoff between the fast and thermal groups.

7. TYPICAL RUNNING TIME

Approximate running time per one depletion step (neutron spectrum calculation, few-group constants generation, and depletion).

PC-386 with 80387 coprocessor: 12 seconds on 20 MHz PC-386

8 seconds on 25 MHz PC-386/Cache

8. COMPUTER HARDWARE REQUIREMENTS

PSU-LEOPARD runs on a PC 80386 personal computer with a math coprocessor.

9. COMPUTER SOFTWARE REQUIREMENTS

The code is written in Fortran 77. The executable files included in the package were created on an 80386 personal computer with 80387 math coprocessor under MS-DOS 4.01 using the Microsoft Fortran 5.0 compiler.

10. REFERENCE

B. G. Petrovic, D. Pevec, "PSU - LEOPARD/RBI Version 90.1," RBI-LP-N-6/90 (1990).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one DS/HD (1.2 MB) 5.25-inch diskette in DOS compressed format including Fortran sources, executables, data file, and sample input and output.

12. DATE OF ABSTRACT

August 1993.