## Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code

## Abstract

In this paper, we introduce a quick method for improving the accuracy of Monte Carlo simulations by generating one- and two-dimensional cross sections at a user-defined temperature before performing transport calculations. A finite difference method is used to Doppler-broaden cross sections to the desired temperature, and unit-base interpolation is done to generate the probability distributions for double differential two-dimensional thermal moderator cross sections at any arbitrarily user-defined temperature. The accuracy of these methods is tested using a variety of contrived problems. In addition, various benchmarks at elevated temperatures are modeled, and results are compared with benchmark results. Lastly, the problem-dependent cross sections are observed to produce eigenvalue estimates that are closer to the benchmark results than those without the problem-dependent cross sections.

- Authors:

- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
- Univ. of Tennessee, Knoxville, TN (United States)

- Publication Date:

- Research Org.:
- Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

- Sponsoring Org.:
- USDOE National Nuclear Security Administration (NNSA)

- OSTI Identifier:
- 1286860

- Alternate Identifier(s):
- OSTI ID: 1358752

- Grant/Contract Number:
- AC05-00OR22725

- Resource Type:
- Accepted Manuscript

- Journal Name:
- Annals of Nuclear Energy (Oxford)

- Additional Journal Information:
- Journal Name: Annals of Nuclear Energy (Oxford); Journal Volume: 88; Journal ID: ISSN 0306-4549

- Publisher:
- Elsevier

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 97 MATHEMATICS AND COMPUTING; 42 ENGINEERING; 99 GENERAL AND MISCELLANEOUS; Monte Carlo; Doppler broadening; Thermal scattering; KENO; SCALE

### Citation Formats

```
Hart, Shane W. D., Celik, Cihangir, Maldonado, G. Ivan, and Leal, Luiz C. Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code. United States: N. p., 2015.
Web. doi:10.1016/j.anucene.2015.10.011.
```

```
Hart, Shane W. D., Celik, Cihangir, Maldonado, G. Ivan, & Leal, Luiz C. Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code. United States. doi:10.1016/j.anucene.2015.10.011.
```

```
Hart, Shane W. D., Celik, Cihangir, Maldonado, G. Ivan, and Leal, Luiz C. Fri .
"Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code". United States. doi:10.1016/j.anucene.2015.10.011. https://www.osti.gov/servlets/purl/1286860.
```

```
@article{osti_1286860,
```

title = {Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code},

author = {Hart, Shane W. D. and Celik, Cihangir and Maldonado, G. Ivan and Leal, Luiz C.},

abstractNote = {In this paper, we introduce a quick method for improving the accuracy of Monte Carlo simulations by generating one- and two-dimensional cross sections at a user-defined temperature before performing transport calculations. A finite difference method is used to Doppler-broaden cross sections to the desired temperature, and unit-base interpolation is done to generate the probability distributions for double differential two-dimensional thermal moderator cross sections at any arbitrarily user-defined temperature. The accuracy of these methods is tested using a variety of contrived problems. In addition, various benchmarks at elevated temperatures are modeled, and results are compared with benchmark results. Lastly, the problem-dependent cross sections are observed to produce eigenvalue estimates that are closer to the benchmark results than those without the problem-dependent cross sections.},

doi = {10.1016/j.anucene.2015.10.011},

journal = {Annals of Nuclear Energy (Oxford)},

number = ,

volume = 88,

place = {United States},

year = {2015},

month = {11}

}

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