1. NAME AND TITLE

ALBEMO: Albedo Monte Carlo Code System.

2. CONTRIBUTOR

INTERATOM, Bensberg, Federal Republic of Germany, via the OECD Nuclear Energy Data Bank, Gif-sur-Yvette, France.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; CDC 6400/6600.

4. NATURE OF PROBLEM SOLVED

ALBEMO calculates the transport of particles (neutrons or gamma-rays) through cavities such as multiple bent pipe ducts or the distribution of particles within empty spaces of large volume. Using a combination of albedo and Monte Carlo methods, it can also be used to calculate the distribution of heat radiation.

5. METHOD OF SOLUTION

ALBEMO is a Monte Carlo code system using the albedo concept. It utilizes a data library with reflection coefficients for determining the energy moderation and, for gamma-rays only, the reflection angle depending on the angle of entry. For reflected neutrons, a cosine-shaped angular distribution is assumed. The data library is produced by a one-dimensional Monte Carlo code. Implementing the albedo concept, ALBEMO assumes that the reflected particles are re-emitted at the same spot where they entered a wall. At any place of the geometry, detector planes can be defined, where the energy and particle fluxes are computed. Provision is made for splitting as a variance-reducing technique.

6. RESTRICTIONS OR LIMITATIONS

Calculations with ALBEMO are accurate, if the dimensions of the empty spaces are large in relation to the migration lengths of the particles within adjacent walls. ALBEMO can only be used for reflection problems. Transmitted particles cannot be considered. X-Y-Z geometry is utilized.

7. TYPICAL RUNNING TIME

No study has been made by RSIC of typical running times for ALBEMO.

8. COMPUTER HARDWARE REQUIREMENTS

ALBEMO runs on standard CDC 6400 or 6600 equipment.

9. COMPUTER SOFTWARE REQUIREMENTS

A FORTRAN IV compiler is required.

10. REFERENCES

K. Muller and H. Vossebrecker, "ALBEMO, A Program for the Calculation of the Radiation Transport in Void Volumes with Reflecting Walls," INTERATOM ITB 75.10 (ORNL-tr-4008) (February 1975).

D. Luigs, "Instruction Notes on the System Library," INTERATOM Memo Nr. D-A 395 (August 1970).

R. Vogt, "Description of the Sub-Program DRUKAS," INTERATOM Memo Nr. 33.798.2 (November 1974).

11. CONTENTS OF CODE PACKAGE

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

12. DATE OF ABSTRACT

October 1978; revised March 1982, January 1983, January 1985.