EQUIPOISE--AN IBM-704 CODE FOR THE SOLUTION OF TWO-GROUP, TWO-DIMENSIONAL, NEUTRON DIFFUSION EQUATIONS IN CYLINDRICAL GEOMETRY

Technical Report · Tue Nov 01 04:00:00 EST 1960

OSTI ID:4124105

Tobias, M L; Fowler, T B

S>An IBM-704 code for the solution of two-group twodimensional neutron- diffusion equations in cylindrical geometry was constructed using FORTRAN. In its present form, the code can treat problems involving a maximum of 625 mesh points (including boundary points). The machine required must be at least 8K with one drum unit and seven tape units. The iterative procedure used is simpler than any currently in use. The "extrapolated Liebmann process" is used to speed convergence. Machine running times and required number of iterations have been comparable with and often less than those required by similar programs. A typical 200-point case convenged in 4 1/2 min and required 50 sweeps through the mesh. Running times are roughly proportional to the number of mesh points. No proofs are presented to guarantee that this program will convenge in all cases which meet the input number requirements. However, no difficulties have yet been experienced in realistic problems, and a special example which combined an extremely bad initial flux guess with awkward material location convenged in a reasonable time (23 min). (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-15-001004
• OSTI ID: 4124105
• Report Number(s): ORNL-2967
• Country of Publication: United States
• Language: English

Related Subjects

ABSORPTION
COMPUTERS
CYLINDERS
DIFFUSION
E-CODES
FORTRAN
GAMMA DETECTION
GROUP THEORY
IBM 704
NEUTRON DETECTION
NEUTRONS
PROGRAMMING
REACTOR CORE
REACTOR TECHNOLOGY