1. NAME AND TITLE

FANG: An Angular Folding Code System for Channel Theory Analysis.

AUXILIARY ROUTINES

DEFILE: Service Routines.

DOT3.5: Two-Dimensional Discrete Ordinates Radiation Transport Code System.

2. CONTRIBUTORS

Oak Ridge National Laboratory, Oak Ridge, Tennessee (A).

Century Research Center Corp., Tokyo, Japan (B).

3. CODING LANGUAGE AND COMPUTER

Fortran IV, Assembler Language; IBM 360/370, CDC.

4. NATURE OF PROBLEM SOLVED

FANG calculates the "contribution flux" and "contribution leakage" necessary for performing "channel theory" analysis and also provides 3-D plots of streaming channels, performs space-energy dependent folding, and computes 2-D angular fluxes. It also calculates the contribution leakage across internal surfaces.

5. METHOD OF SOLUTION

FANG uses information available on a DOT scalar flux tape for performing its analyses. It calculates "channel theory" analysis functions by using various folding options for direction, interval, and group. It calculates angular forward and adjoint fluxes by group, interval, and angle from expansion of Legendre moments on DOT scalar flux tape.

FANG is flexibly dimensioned and reads input in fixed or free form FIDO format. Forward and adjoint fluxes are assumed available from previous DOT calculations.

6. RESTRICTIONS OR LIMITATIONS

The user should be aware that reconstructed forward and adjoint angular fluxes are used in the calculation of the contribution flux; if unreasonable answers appear (e.g., negative values), the number of moments input to FANG should be checked.

7. TYPICAL RUNNING TIME

On an IBM 360/91 computer, relatively complex problems take from 1 to 3 minutes.

8. COMPUTER HARDWARE REQUIREMENTS

FANG is operable on the IBM 360/370 or the CDC computers. A large problem requires approximately 540 K bytes.

9. COMPUTER SOFTWARE REQUIREMENTS

Fortran IV and Assembler Language compilers are required.

10. REFERENCE

M. L. Williams and F. B. Sadler, "The Fang Angular Folding Code for Channel Theory Analysis," ORNL/TM-5228 (August 1977).

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

March 1984.