1. NAME AND TITLE

KAMCCO: Three-Dimensional Time Dependent Monte Carlo Code System for Fast Neutron Physics Problems.

2. CONTRIBUTOR

Gesellschaft fur Kernforschung, Institute for Neutron Physics and Reactor Technology, Karlsruhe, Federal Republic of Germany, through the OECD NEA Data Bank, Gif-sur-Yvette, France.

3. CODING LANGUAGE AND COMPUTER

Fortran IV, Assembler language; IBM 370.

4. NATURE OF PROBLEM SOLVED

KAMCCO is a three-dimensional Monte Carlo code system designed for fast neutron reactor physics problems. It includes time dependence and a continuous treatment of the energy. The geometry must be defined in terms of surfaces up to second order. Two options are available: (a) census time scheme for time dependent inhomogeneous neutron transport problems, and (b) source iteration for static eigenfunction problems.

Neutron collisions are treated on a per isotope basis. Elastic scattering retains first order anisotropy in the center-of-mass system. Inelastic scattering is processed via the evaporation model or via the excitation of discrete levels, depending on the pre-collision energy.

5. METHOD OF SOLUTION

The Monte Carlo techniques are mostly analog. Importance sampling is involved in the collision physics, and Russian roulette and splitting are employed to a minor extent. Estimates are obtained from the collision, the track length estimator, and their linear combination. Eigenfunction problems are handled by a variant of the power method.

6. RESTRICTIONS OR LIMITATIONS

The maximum number of isotopes (fissile isotopes) is 30 (10). Most data fields have variable dimensions. The few exceptions can be easily extended by strictly logical changes.

7. TYPICAL RUNNING TIME

For a medium sized fast critical assembly (Sneak 3A1) with 8 isotopes, a standard error 0.005 in the static eigenvalue is obtained in 12 minutes on the IBM 370/168.

8. COMPUTER HARDWARE REQUIREMENTS

KAMCCO requires at least 230 K bytes of main storage on an IBM 370 computer, but no external storage. The availability of a clock routine which measures CPU time is a great advantage, but not absolutely necessary.

9. COMPUTER SOFTWARE REQUIREMENTS

Fortran IV and Assembler compilers and assemblers are required.

10. REFERENCE

a. Included in the documentation:

G. Arnecke, H. Borgwaldt, V. Brandl, and M. Lalovic, "KAMCCO, A Reactor Physics Monte Carlo Neutron Transport Code," KFK-2190 (June 1975).

b. Background information:

G. Arnecke, et al., "KAMCCO, Ein Reaktorphysikalischer Monte-Carlo-Neutronentransport-Code," KFK 2190 (1975) in German.

G. Arnecke, et al., "Efficient Data Management Techniques Implemented in the Karlsruhe Monte Carlo Code KAMCCO," NEA-CRP-L-118 (ANL-75-2), p. 5-17 (1974).

H. Borgwaldt, "Comparison of 3 Methods to Control the Leakage of Particles in a Monte Carlo Game," KFK 1391 (1971).

V. Brandl, "Die Monte-Carlo Berechnung von Quotienten in der Reaktorphysik," KFK 2074 (1975).

B. Hinkelmann, et al., "Status of the Karlsruhe Evaluated Nuclear Data File KEDAK in June 1970," KFK 1340 (1971).

11. CONTENTS OF CODE PACKAGE

Included are the referenced document and one (1.2MB) DOS diskette which contains the source code and sample problem input and output.

12. DATE OF ABSTRACT

August 1979; revised March 1982, February 1983, January 1984.

KEYWORDS: MONTE CARLO; NEUTRON; TIME-DEPENDENT; COMPLEX GEOMETRY