IAEA0888 PSU-LEOPARD/RBI.

1. NAME OR DESIGNATION OF PROGRAM:  PSU-LEOPARD/RBI.

3. DESCRIPTION OF PROBLEM OR FUNCTION

LEOPARD is a unit cell code for generating two and/or four group constants for PWR fuel assemblies.  It assumes that the fuel assembly consists of a large array of identical unit cells, each unit cell being composed of a fuel pin and cladding, surrounded by a moderator. A non-lattice part of the fuel assembly is accounted for by introducing an "extra" region.
The most important feature of PSU-LEOPARD is the capability to fit the group constants as polynomials in burnup and soluble boron concentration, providing easily accessible data for in-core fuel management calculations. The polynomial coefficients are stored in a file called ADD (Assembly Data Description) in a format compatible with the MCRAC code.
RBI version 90.1 of PSU-LEOPARD (PC, IBM mainframe and VAX versions) includes a restart option, numerically more stable polynomial fit, PC and VAX timing routines, and a few other new options.

4. METHOD OF SOLUTION

LEOPARD is a spectrum dependent non-spatial depletion code, based on the modified MUFT and SOFOCATE models. The  MUFT model, dividing the fast energy range into 54 energy groups, calculates the fast constants by utilizing the B1 and Grueling-Goertzel approximations. The SOFOCATE model, representing the thermal energy range by 172 energy levels, calculates the thermal constants averaged over the Wigner-Wilkins spectrum. ABH method is used to homogenize the unit cell for each energy level to  provide the equivalent homogeneous macroscopic cross sections for use with Wigner-Wilkins spectrum. The LEOPARD energy range is from zero eV to 10 MeV with a 0.625 eV cutoff between the fast and thermal groups.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

PSU-LEOPARD works with nuclides commonly used in water reactors. Thorium and U-238 chains are allowed.

6. TYPICAL RUNNING TIME

Approximate running time per one depletion step (neutron spectrum calculation, few-group constants generation,  and depletion):
A) PC with 80x87 coprocessor
   96 seconds on 10 MHz PC-XT
   52 seconds on 12 MHz PC-AT
   19 seconds on 20 MHz PC-386
   14 seconds on 25 MHz PC-386/Cache
B) PC-386 with 80387 coprocessor
   12 seconds on 20 MHz PC-386
    8 seconds on 25 MHz PC-386/Cache
C) IBM mainframe
    6 seconds CPU on IBM-4341 (IBM VS FORTRAN)
D) VAX
   13 seconds CPU on VAX-11/750 (VAX-11 FORTRAN77)

7. UNUSUAL FEATURES OF THE PROGRAM

Group constants are fitted by polynomials in burnup and in soluble boron concentration providing a complete set of data for automated core depletion.

8. RELATED AND AUXILIARY PROGRAMS

Relation to previous version - The original IBM mainframe version of PSU-LEOPARD was developed by Prof. S.H. Levine of Penn State University and released earlier to NEA DB (Package-ID IAEA 0888/01). The RBI version offers:
- source in FORTRAN77 standard;
- version for PC, IBM mainframe, and VAX;
- binary library conversion program;
- several new options.
Auxiliary programs - DECTOBIN, and auxiliary program (included with  the package) for converting LEOPARD library from decimal to binary form; used to facilitate installation and/or transfer to different computers.
Related programs - MCRAC/RBI version 90.1.
PSU-LEOPARD/RBI and MCRAC/RBI (Multiple Cycle Reactor Analysis Code) form the computer code system PFMP/RBI (Penn State Fuel Management Package, RBI version). PSU-LEOPARD/RBI is used to prepare group constants for global core analysis code, MCRAC/RBI.

10. REFERENCES

- L.E. Strawbridge and R.F. Barry:
  Criticality Calculations for Uniform Water Moderated Lattices
  Nucl. Sci. Eng., 23, 58 (1965).
- S.H. Levine:
  In-Core Fuel Management
  Educational Module No. 5, Editor Dean Eckoff, Kansas State
  University (1980).
- D. Pevec:
  In CORE FUEL MANAGEMENT - PWR Constants Generation Using
  PSU-LEOPARD Code
  Lecture notes, Workshop on Reactor Physics Calculations for
  Applications in Nuclear Technology, ITCP Trieste (1990).

- B.G. Petrovic and D. Pevec:
  PSU-LEOPARD/RBI Version 90.1 User's Guide
  RBI-LP-N-6/90 (1990).
- In-Core Fuel Management Programs for Nuclear Power Reactors
  IAEA-TECDOC-314  (October 1984)
- B.G. Petrovic and D. Pevec:
  PSU-LEOPARD/RBI Version 90.1 User's Guide
  RBI-LP-N-6/90 (1990).
- In-Core Fuel Management Programs for Nuclear Power Reactors
  IAEA-TECDOC-314  (October 1984)

11. MACHINE REQUIREMENTS

A) About 369 KB of available (free) RAM memory required;
   hard disk and mathematical coprocessor recommended.
B) About 360 KB of available of available (free) RAM memory and  mathematical coprocessor, NDP FORTRAN-386 and Phar Lap Tools    required;
   hard disk recommended.
C) About 400 KB of main memory.
D) About 400 KB of main memory.

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED

A) MS-DOS or PC-DOS on PC-XT/AT/386
B) MS-DOS or PC-DOS and Phar Lap Tools on PC-386
C) OS/VS, OS2/MVS, CMS, or similar on IBM mainframe
D) VMS on VAX

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

- On PC-386, version B is about 1.6 times faster than version A, but   requires NDP FORTRAN-386 compiler and Phar Lap Tools.
- Timing routines are provided through FORTRAN calls in PC and VAX  version. To avoid subroutines in assembly language, no timing is  provided in IBM mainframe version (CPU accounting automatically   done by OS).
- It is possible to recompile and run PSU-LEOPARD on a PC without   coprocessor, but the running time increases significantly.
- On some non-100% IBM-compatible PC-XTs, unexpected floating-point   exceptions may occur. This problem has not been noticed on PC-AT   and PC-386 compatibles.

15. NAME AND ESTABLISHMENT OF AUTHOR

RBI Version 90.1 (A, B, C, and D)           B.G. Petrovic, T. Smuc, D. Pevec, and D. Grgic
          Ruder Boskovic Institute
          Bijenicka c. 54, P.O. Box 1016
          4100 Zagrab, Yugoslavia

File name	File description	Records
IAEA0888_04.001	Information file	58
IAEA0888_04.002	Command file to run DECTOBIN	9
IAEA0888_04.003	Library in decimal format	6347
IAEA0888_04.004	DECTOBIN source file	91
IAEA0888_04.005	DECTOBIN executable file	0
IAEA0888_04.006	Command file to run LEO	21
IAEA0888_04.007	Binary library	0
IAEA0888_04.008	Sample problem 1 input	12
IAEA0888_04.009	Sample problem 2 input	33
IAEA0888_04.010	LEO source file	3195
IAEA0888_04.011	LEO executable file	0
IAEA0888_04.012	Sample problem 1 output	318
IAEA0888_04.013	Sample problem 2 add deck	61
IAEA0888_04.014	Sample problem 2 output	2697

File name	File description	Records
IAEA0888_05.001	Information file	67
IAEA0888_05.002	Batch file to compile and link DECTOBIN	1
IAEA0888_05.003	Batch file to compile and link LEO	1
IAEA0888_05.004	Batch file to run DECTOBIN	1
IAEA0888_05.005	Batch file to run Sample Problem 1	1
IAEA0888_05.006	Batch file to run Sample Problem 2	1
IAEA0888_05.007	Sample Problem 1 input	12
IAEA0888_05.008	Sample Problem 2 input	33
IAEA0888_05.009	DECTOBIN Source file	91
IAEA0888_05.010	LEO0 source file	110
IAEA0888_05.011	LEO1 source file	698
IAEA0888_05.012	LEO2 source file	387
IAEA0888_05.013	LEO3 source file	632
IAEA0888_05.014	LEO4 source file	716
IAEA0888_05.015	LEO5 source file	605
IAEA0888_05.016	DECTOBIN executable file	0
IAEA0888_05.017	LEO executable file	0
IAEA0888_05.018	LEO Binary Library	0
IAEA0888_05.019	LEO Decimal Library	6347
IAEA0888_05.020	Sample problem 2 punched output	61
IAEA0888_05.021	Sample problem 1 output	325
IAEA0888_05.022	Sample problem 2 output	2742
IAEA0888_05.023	DOS file-names	22