1. NAME AND TITLE

SNEX: A One-Dimensional Single Group Discrete Ordinates Transport Code System.

2. CONTRIBUTOR

Los Alamos National Laboratory, Los Alamos, New Mexico.

3. CODING LANGUAGE AND COMPUTER

Fortran IV; CDC.

4. NATURE OF PROBLEM SOLVED

SNEX exactly solves the spatial single group, one-dimensional (plane, cylinder, sphere) discrete ordinates transport equations with diamond approximation for the angular fluxes. Its purposes are to provide a standard for comparisons of spatial differencing schemes as well as an exact numerical solution to the discrete ordinates equations in one-dimensional geometries.

5. METHOD OF SOLUTION

SNEX solves the single group transport equation with isotropic scattering for specified left and right boundary conditions. Full solutions are generated by numerically integrating the inhomogeneous source terms and adding them to the homogeneous (analytic) solutions in the standard fashion. Simple relationships between angular quadratures permit application of the method to plane, cylindrical, and spherical geometries.

6. RESTRICTIONS OR LIMITATIONS

Analysis is confined to isotropic scattering.

7. TYPICAL RUNNING TIME

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

8. COMPUTER HARDWARE REQUIREMENTS

SNEX is operable on the CDC computer.

9. COMPUTER SOFTWARE REQUIREMENTS

A Fortran IV compiler is required.

10. REFERENCE

B. R. Wienke, "SNEX: Semianalytic Solution of the One-Dimensional Discrete Ordinates (S_n) Transport Equations with Diamond Differenced Angular Fluxes," LA-7879-MS (June 1979).

11. CONTENTS OF CODE PACKAGE

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

12. DATE OF ABSTRACT

January 1982.