1. NAME AND TITLE

SPHINX: A One-Dimensional Diffusion and Transport Nuclear Cross Section Processing Code System.

2. CONTRIBUTORS

Westinghouse Advanced Reactors Division, Madison, Pennsylvania.

Computer Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee.

3. CODING LANGUAGE AND COMPUTER

Fortran IV, Assembler Language; CDC-7600, IBM 360/370.

4. NATURE OF PROBLEM SOLVED

SPHINX provides a standardized calculational scheme for generating multigroup cross sections. It interpolates to the correct composition-dependent self-shielding factors, provides elastic matrix removal corrections if requested, and space-energy collapses or cell homogenizes the resultant cross sections to a desired group structure for subsequent spatial calculations.

5. METHOD OF SOLUTION

SPHINX incorporates both one-dimensional diffusion and transport theory. SPHINX is standardized in that it uses a set of standard interface files as input and output and can be linked with other codes which use the same. The basic input to SPHINX consists of cross sections and self-shielding factors in standard interface format. The code uses one-dimensional diffusion theory or one-dimensional transport theory to space-energy collapse the cross sections to the desired group structure. Cell homogenization of the composition and temperature-corrected cross sections using transport fluxes are also available in SPHINX.

The self-shielding factor interpolation is a Lagrangian-interpolation scheme with safeguards to prevent unreasonable interpolation. The heterogeneity effects are based on the approximate methods of Sauer, Bell, Levine, and Wigner. PSR-96/1DX is the source for the elastic transfer corrections (as suggested by Bondarenko, et al.), the space energy collapse, and the diffusion theory one-dimensional space calculation. Cell homogenization of user specified cross sections is accomplished by using fluxes from one-dimensional space calculation. The transport theory one-dimensional space calculation is that of CCC-254/ANISN-ORNL.

6. RESTRICTIONS OR LIMITATIONS

Available core storage affects the size of the problem which can be executed. However, SPHINX is variably dimensioned to allow a wide range of problems to be run.

7. TYPICAL RUNNING TIME

The running time is dependent upon the problem size and upon the data transfer speeds of a particular system.

8. COMPUTER HARDWARE REQUIREMENTS

SPHINX is operable on the CDC-7600 computer (A) or the IBM 360/370 computers (B). 50,000 words of core storage and a reasonable amount of disk and/or tape backing storage are required.

9. COMPUTER SOFTWARE REQUIREMENTS

Fortran IV and Assembler Language compilers are required.

10. REFERENCES

a. Included in the documentation:

W. J. Davis, M. B. Yarbrough, and A. B. Bortz, "SPHINX, A One Dimensional Diffusion and Transport Nuclear Cross Section Processing Code," WARD-XS-3045-17 (August 1977).

R. Q. Wright, "SPHINX: Resonance and One Dimensional Diffusion Theory Nuclear Cross Section Processing Code (IBM Version)," Draft (March 1978).

b. Background information:

G. I. Bell, "A Simple Treatment for Effective Resonance Absorption Cross Sections in Dense Lattices," Nucl. Sci. Eng. 5 (1959) 138-139.

I. I. Bondarenko, ed., "Group Constants for Nuclear Reactor Calculations," New York: Consultants Bureau. 1964.

W. W. Engle, Jr., "A Users Manual for ANISN: A One Dimensional Discrete Ordinates Transport Code with Anisotropic Scattering," K-1693 (1967, updated June 1973).

R. W. Hardie and W. W. Little, Jr., "1DX: A One-Dimensional Diffusion Code for Generating Effective Nuclear Cross Sections," BNWL-954 (March 1969).

M. M. Levine, "Resonance Integral Calculations for U²³⁸ Lattices," Nucl. Sci. Eng. 16 (1963) 271-279.

A. Sauer, "Approximate Escape Probabilities," Nucl. Sci. Eng. 16 (1963) 329-335.

E. P. Wigner, E. Creutz, H. Jupnik, and T. Snyder, "Resonance Absorption of Neutrons by Spheres," J. Appl. Phys. 26 (1955) 260-270.

11. CONTENTS OF CODE PACKAGE

Included are the referenced documents (10.a) and one (1.2MB) DOS diskette which contains the source code and sample problem input.

12. DATE OF ABSTRACT

March 1984.