# PROGRAM ODD--A ONE-DIMENSIONAL MULTIGROUP CODE FOR THE IBM-7090 (ANP PROGRAM NO. 657)

## Abstract

The physical and mathematical reactor models which are used in Program ODD are discussed. In addition, the FORTRAN II source program listings, decimal data input sheets, and input and output for a sample case are given. Program ODD was designed to raake use of the Revised Nuclear Data System at ANPD which consists of twenty-five energy group cross-section data including high energy inelastic scattering matrices, resonance parameters for the resolved resonances, and thermalization scattering matrices for the near thermal energy region. The most unique aspect of the program is the mathematical technique employed for eliminating inner iterations and slow convergenc rates occasioned by the up- scattering'' in the thermalization region of the energy lattice. Direct inversion of the energy matrix coupling the thermal and last four epitherma groups provides simultaneous consistent solutions for thes groups within each power iteration. (auth)

- Authors:

- Publication Date:

- Research Org.:
- General Electric Co. Flight Propulsion Lab. Dept., Cincinnati

- OSTI Identifier:
- 4802696

- Report Number(s):
- APEX-702

- NSA Number:
- NSA-16-010379

- DOE Contract Number:
- AF33(600)-38062; AND AT(11-1)-171

- Resource Type:
- Technical Report

- Resource Relation:
- Other Information: Orig. Receipt Date: 31-DEC-62

- Country of Publication:
- United States

- Language:
- English

- Subject:
- MATHEMATICS AND COMPUTERS; COMPUTERS; CROSS SECTIONS; ENERGY; ENERGY RANGE; FORTRAN; GROUP THEORY; IBM 7090; LATTICES; NEUTRONS; PROGRAMMING; REACTORS; RESONANCE; SCATTERING; THERMAL NEUTRONS

### Citation Formats

```
Fischer, P.G., Wenstrup, F.D., and Hoffman, T.A.
```*PROGRAM ODD--A ONE-DIMENSIONAL MULTIGROUP CODE FOR THE IBM-7090 (ANP PROGRAM NO. 657)*. United States: N. p., 1961.
Web. doi:10.2172/4802696.

```
Fischer, P.G., Wenstrup, F.D., & Hoffman, T.A.
```*PROGRAM ODD--A ONE-DIMENSIONAL MULTIGROUP CODE FOR THE IBM-7090 (ANP PROGRAM NO. 657)*. United States. doi:10.2172/4802696.

```
Fischer, P.G., Wenstrup, F.D., and Hoffman, T.A. Fri .
"PROGRAM ODD--A ONE-DIMENSIONAL MULTIGROUP CODE FOR THE IBM-7090 (ANP PROGRAM NO. 657)". United States. doi:10.2172/4802696. https://www.osti.gov/servlets/purl/4802696.
```

```
@article{osti_4802696,
```

title = {PROGRAM ODD--A ONE-DIMENSIONAL MULTIGROUP CODE FOR THE IBM-7090 (ANP PROGRAM NO. 657)},

author = {Fischer, P.G. and Wenstrup, F.D. and Hoffman, T.A.},

abstractNote = {The physical and mathematical reactor models which are used in Program ODD are discussed. In addition, the FORTRAN II source program listings, decimal data input sheets, and input and output for a sample case are given. Program ODD was designed to raake use of the Revised Nuclear Data System at ANPD which consists of twenty-five energy group cross-section data including high energy inelastic scattering matrices, resonance parameters for the resolved resonances, and thermalization scattering matrices for the near thermal energy region. The most unique aspect of the program is the mathematical technique employed for eliminating inner iterations and slow convergenc rates occasioned by the up- scattering'' in the thermalization region of the energy lattice. Direct inversion of the energy matrix coupling the thermal and last four epitherma groups provides simultaneous consistent solutions for thes groups within each power iteration. (auth)},

doi = {10.2172/4802696},

journal = {},

number = ,

volume = ,

place = {United States},

year = {1961},

month = {6}

}