IAEA0889 MCRAC/RBI.

1. NAME OR DESIGNATION OF PROGRAM:  MCRAC/RBI.

3. DESCRIPTION OF PROBLEM OR FUNCTION

MCRAC is a two-dimensional, two-group diffusion code for global core analysis developed for in-core fuel management applications. It performs both nucleonic and economic analysis of PWR core over multiple cycles. MCRAC requires cross sections in the form of polynomials in burnup and in  soluble boron concentration, as generated by the PSU-LEOPARD code. The main features and options of MCRAC are:
  - x-y or r-z geometry
  - neutron diffusion approximation
  - 2-group or 1.5-group neutron diffusion model
  - multiple cycle power distribution and depletion calculation
  - multiple cycle fuel cost analysis
  - critical soluble boron concentration search
  - spatial power-dependent xenon-135 feedback modelling
  - control rod and burnable absorber simulation
  - search for LP with flat BOC power distribution
  - artificial ADDs
  - extensive printout control
  - variable dimensioning technique.
RBI version 90.1 of MCRAC is available for PC, IBM mainframe, and VAX. It offers:
  - compatibility with PSU-LEOPARD/RBI
  - the code is now completely in FORTRAN-77
  - timing routines for PC and VAX
  - more convenient input structure (ADD decks in a separate file)
  - fuel interchange option.

4. METHOD OF SOLUTION

Core neutronics is modelled in two group, two dimensional diffusion approximation. The EQUIPOISE method is employed to solve the finite-difference discretized form. Programming techniques are based on the EXTERMINATOR-II code.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM

Variable dimensioning technique is used to store most of variables in just one huge array. The size of that array determines the allowed sum of dimensions of individual variable, i.e., the complexity of the problem. That array size may be easily increased depending on the available main memory.

6. TYPICAL RUNNING TIME

Approximate running time for a complete cycle analysis (core quadrant modelled in X-Y geometry, 2-group model, 8
depletion steps, critical boron concentration search at each step, 19x19 mesh points, pointwise convergence criterion 0.0001):
A) PC with 80x87 coprocessor
46 min on 10 MHz PC-XT
22 min on 12 MHz PC-AT
9 min on 20 MHz PC-386
6 min on 25 MHz PC-386/Cache
B) PC-386 with 80387 coprocessor
4.5 min on 20 MHz PC-386
3.0 min on 25 MHz PC-386/Cache
C) IBM mainframe
2.5 min on IBM-4341 (IBM VS FORTRAN)
D) VAX
5.5 min CPU on VAX-11/750 (VAX-11 FORTRAN77)

NEA-DB ran the test case included in the package on a 66-MHz PC/80486 in one minute of elapsed time.

7. UNUSUAL FEATURES OF THE PROGRAM

  - variable dimensioning technique
  - polynomial cross sections representation (ADDs)
  - multicycle neutronic/cost analysis
  - fuel interchange option.

8. RELATED AND AUXILIARY PROGRAMS

Relation to previous version - The original IBM mainframe version of MCRAC was developed by Prof. S.H. Levine of Penn State University and released earlier to NEA DB (Package-ID IAEA 0889/01).
The RBI version offers:
  - source in FORTRAN77 standard
  - version for PC, IBM mainframe, and VAX
  - several new options.
Related programs - PSU-LEOPARD/RBI version 90.1.
PSU-LEOPARD/RBI and MCRAC/RBI form the computer code system PFMP/RBI (Penn State Fuel Management Package, RBI version). PSU-LEOPARD/RBI is used to prepare group constants for MCRAC/RBI.

10. REFERENCES

- S.H. Levine
  Module 5: In-Core Fuel Management, in Nuclear Fuel Cycle
  Educational Module Series (ed. N.D. Eckhoff),
  Kansas State University (1980).
- M.L. Tobias and T.B. Fowler
  The EQUIPOISE Method - A Simple Procedure for Group-Diffusion
  Calculations in Two and Three Dimensions
  Nucl. Sci. Eng., 12, 513 (1962).
- T.B. Fowler, M.L. Tobias, and D.R. Vondy
  EXTERMINATOR-II, A FORTRAN Code for Solving Multigroup Diffusion
  Equation in Two Dimensions
  ORNL-4078, Oak Ridge National Laboratory (1967).
- B.G. Petrovic
  In Core Fuel Management: PWR Core Calculations Using MCRAC,
  Lecture notes, Workshop on Reactor Physics Calculations for
  Applications in Nuclear Technology
  ICTP, Trieste (1990).

- B.G. Petrovic and D. Pevec:
  MCRAC/RBI Version 90.1 Use's Guide
  RBI-LP-N-12/90 (1990).
- In-Core Fuel Management Programs for Nuclear Power Reactors
  IAEA-TECDOC-314 (October 1984).

11. MACHINE REQUIREMENTS

A) About 480 KB of available (free) RAM memory required
Hard disk and mathematical coprocessor recommended.
B) About 480 KB of available (free) RAM memory and mathematical
coprocessor, NDP FORTRAN-386 and Phar Lap Tools required
Hard disk recommended.
C) About 600 KB of main memory
D) About 600 KB of main memory

NEA-DB used a DELL 466/L PC (80486 processor, 66 MHz, 8 Mbytes of RAM).

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

The tests were performed under MS-DOS 6.0 with the MicroSoft compiler Version 5.1.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS

- On PC-386, version B is about two 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 MCRAC on a PC without   coprocessor, but the running time increases significantly.

15. NAME AND ESTABLISHMENT OF AUTHOR

This code system has been included in the Coordinated Research Programme (CRP) on "Codes Adaptable to Small and Medium-Size Com- puters Available in Developing Countries for In-Core Fuel Manage- ment" of the International Atomic Energy Agency.

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

File name	File description	Records
IAEA0889_05.001	Information file	109
IAEA0889_05.002	FORTRAN source	164
IAEA0889_05.003	FORTRAN source	430
IAEA0889_05.004	FORTRAN source	590
IAEA0889_05.005	FORTRAN source	594
IAEA0889_05.006	FORTRAN source	572
IAEA0889_05.007	FORTRAN source	618
IAEA0889_05.008	FORTRAN source	446
IAEA0889_05.009	FORTRAN source	578
IAEA0889_05.010	FORTRAN source	412
IAEA0889_05.011	FORTRAN source	598
IAEA0889_05.012	Executable file	0
IAEA0889_05.013	Compile and link command	1
IAEA0889_05.014	Sample problem (input)	41
IAEA0889_05.015	Sample problem (input ADD file)	238
IAEA0889_05.016	Sample problem (output)	1323
IAEA0889_05.017	Command to run sample problem	1
IAEA0889_05.018	FORTRAN source	4999
IAEA0889_05.019	Compile and link command	1
IAEA0889_05.020	Sample problem (input)	41
IAEA0889_05.021	Sample problem (input ADD file)	238
IAEA0889_05.022	Sample problem (output)	1320
IAEA0889_05.023	Command to run sample problem	3
IAEA0889_05.024	DOS file-names	23