1. NAME AND TITLE

SDC: Kernel Integration Shield Design Code for Radioactive Fuel Handling Facilities.

AUXILIARY ROUTINES

TABLES: Data Edit.

PHOEBE: Source Strength Generator.

The PHOEBE code is a revised and expanded version of the Internuclear Company EAPRR Code.

The code package was originally developed for the IBM 7090 and CDC 1604; was later converted to run on the IBM 360/370. It is also available in the OECD NEA Data Bank.

SDC has been widely used; was distributed by RSIC 106 times since it was packaged in 1965.

2. CONTRIBUTOR

Chemical Technology and Engineering Divisions, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

FORTRAN IV; IBM 360/370.

4. NATURE OF PROBLEM SOLVED

SDC is designed to calculate the gamma-ray shielding requirements for chemical processing, fabrication, or fuel handling facilities. It will handle 13 source geometries (point, line, disk, plane, slab, cylinder with shield at side, cylinder with shield at end, sphere, ring, rod cluster, skew line, annular cylinder with shield at side, and annular cylinder with shield at end) either unshielded or shielded by slab shields. Materials of construction for shield, cladding, or source volume may be selected from a list of 17. As many as 12 gamma-ray energy groups, covering an energy range of 0.10 to 10 MeV, with corresponding source strengths, may be used to describe the gamma-ray spectrum.

The PHOEBE code was developed to calculate the decay properties of mixed fission products resulting from the fission of 235U. Fission product beta-ray and gamma- ray activity and spectra are the primary quantities calculated.

5. METHOD OF SOLUTION

Integration of the basic exponential attenuation point kernel over the various geometries provides the uncollided gamma-ray flux in SDC. Speed is achieved by utilizing many of the integrations found in Rockwell (see References, b.). Biological dose rate was obtained by multiplying this uncollided flux by the product of a flux-weighted buildup factor and a dose-conversion factor. Two major options in the code permit calculation of (1) required shield thickness when a dose-rate level is specified, or (2) dose rate when the shield thickness is given. Calculation of dose rates from unshielded sources as well as surface intensities for cylinders and spheres is also included.

Results from PHOEBE are given in terms of photon-emission rates for each group, gamma-ray energy emission rates for each group, total gamma-ray emission rate, total gamma-ray energy emission rate, beta particle emission, total average beta-ray energy emission rate, and total energy release rate.

6. RESTRICTIONS OR LIMITATIONS

12 energy groups, 0.1 to 10 MeV.

17 materials.

7. TYPICAL RUNNING TIME

Average running time for SDC: 0.01 hour per case. No study has been made for typical running time for PHOEBE.

8. COMPUTER HARDWARE REQUIREMENTS

The code is operable on the IBM 360/370. Only 3 tape units are required.

9. COMPUTER SOFTWARE REQUIREMENTS

The IBM FORTRAN (level H) Compiler for the 360/370 may be used. Normally, only systems, input and output tapes are used. A scratch tape is used by TABLES.

10. REFERENCES

a. Included in package:

E. D. Arnold and B. F. Maskewitz, SDC, A Shielding Design Calculation Code for Fuel-Handling Facilities, ORNL-3041 (March 1966).

E. D. Arnold, PHOEBE A Code for Calculating Beta and Gamma Activity and Spectra for 235U Fission Products, ORNL-3931 (March 1966).

b. Background information:

T. Rockwell, Reactor Shielding Design Manual, D. Van Nostrand Company (1956).

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents and a reel of tape which contains the source codes and input for a sample problem written in BCD/EBCDIC card images and output from the sample problem written in list format; total records 7631.

12. DATE OF ABSTRACT

January 1968; updated July 1981.

KEYWORDS: FISSION PRODUCT INVENTORY; GAMMA-RAY; SOURCE STRENGTH; KERNEL; FUEL-HANDLING FACILITIES