1. NAME AND TITLE

TRANSHEX: Two-dimensional Multigroup Collision Probability Code System for Hexagonal Geometry.

2. CONTRIBUTOR

Technical Research Center of Finland, Nuclear Engineering Laboratory, Helsinki, Finland.

3. CODING LANGUAGE AND COMPUTER

Fortran V; UNIVAC 1108.

4. NATURE OF PROBLEM SOLVED

TRANSHEX is a multigroup integral transport program that determines the thermal scalar flux distribution arising from a known epithermal flux in two-dimensional hexagonal geometry.

5. METHOD OF SOLUTION

TRANSHEX solves the isotropic collision probability equations for a region-averaged scalar flux by an iterative method. Either a successive over-relaxation or an inner-outer iteration technique is applied. Flat flux collision probabilities between trigonal space regions with white boundary condition are utilized. The effect of epithermal flux is taken into consideration as a slowing down source that is calculated for a given spatial distribution and 1/E energy dependence of the epithermal flux.

6. RESTRICTIONS OR LIMITATIONS

None noted.

7. TYPICAL RUNNING TIME

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

8. COMPUTER HARDWARE REQUIREMENTS

Organized as an overlay structure, TRANSHEX requires about 13.6 K words core memory plus the memory required by array T on the UNIVAC 1108. If no overlay structure is used, the memory required is about 18 K words plus the array T.

9. COMPUTER SOFTWARE REQUIREMENTS

TRANSHEX runs under the EXEC 8 operating system.

10. REFERENCE

E. Patrakka, "TRANSHEX: A Two-dimensional Multigroup Collision Probability Computer Program for Hexagonal Geometry" (June 1973).

11. CONTENTS OF CODE PACKAGE

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

12. DATE OF ABSTRACT

January 1984.