## RSICC CODE PACKAGE CCC-763

### 1. NAME AND TITLE

SOLTRAN: Solving Multi-Dimensional Simplified
P2 Transport and Diffusion Problems of Hexagonal Geometry in Fast Reactors.

### 2. CONTRIBUTORS

Korea Atomic Energy Research Institute, Daejon, Republic of
Korea through the OECD Nuclear Energy Agency Data Bank, Issy-Les Moulineaux, France.

### 3. CODING LANGUAGE AND COMPUTER

FORTRAN 90, PC Windows (C00763PCX8600).

### 4. NATURE OF PROBLEM SOLVED

SOLTRAN is a computer code for solving
the multi-dimensional simplified P2 (SP2) transport and diffusion problems of a
hexagonal geometry by a nodal expansion method for an analysis of fast
reactors.

### 5. METHOD OF SOLUTION

The nodal SP2 equations are formulated with minimum
modifications of the nodal diffusion equation by introducing the SP2 constant
and flux. The response matrix equations that are the final forms of the nodal
equations involve the spatial flux moments, the surface-averaged flux, the
surface-averaged partial current, and the surface averaged sources, where the
last terms are used in the SP2 option only. These equations are solved using a fission
source iteration with red-black and coarse-mesh rebalancing acceleration.

### 6. RESTRICTIONS OR LIMITATIONS

Because the SP2 and diffusion equations can be considered
as an asymptotic approximation of a transport equation in optically thick
regions, relatively larger errors occur in the regions with long diffusion
lengths. But the magnitudes of the errors of the SP2 nodal are smaller than
those of the diffusion nodal.

### 7. TYPICAL RUNNING TIME

Run time was on the order of a few seconds.

### 8. COMPUTER HARDWARE REQUIREMENTS

X86 or X86_64 processor.

### 9. COMPUTER SOFTWARE REQUIREMENTS

Windows operating system with Compaq Fortran compiler 6.1 or
higher is required to compile source.

### 10. REFERENCES

Yeong-il Kim, Taek Kyum Kim, Young-Jin Kim: “User's Manual
for SOLTRAN (Version 1.0) - A Code for Solving Multi-Dimensional Simplified P2
Transport Theory Problems in a Hexagonal Geometry” (January 2000).

### 11. CONTENTS OF CODE PACKAGE

The package is transmitted on a CD in a Windows format file which
includes documentation, source files, precompiled executables and a sample
problem.

### 12. DATE OF ABSTRACT

September 2012.

**KEYWORDS:** DIFFUSION THEORY, MULTIGROUP