# CMFD acceleration of spatial domain-decomposed neutron transport problems

## Abstract

A significant limitation to parallelizing the solution of neutron transport problems is the need for sweeps across the entirety of the problem domain. Angular domain decomposition is common practice, as the equations for each direction are independent aside from their shared scattering/fission source. Accordingly, spatial domain decomposition does not naturally arise in the transport equations and is therefore less frequent in practice. In this paper, we show that a neutron transport domain can be straightforwardly divided into independent, parallelizable sweep regions, globally linked with the standard CMFD method, with an additional update equation. We verify, theoretically (via Fourier analysis) and computationally, that the convergence properties of this method are stable and nominally as rapid as standard CMFD. (authors)

- Authors:

- Dept. of Nuclear Engineering and Radiological Sciences, Univ. of Michigan, Ann Arbor, MI 48109-2104 (United States)

- Publication Date:

- Research Org.:
- American Nuclear Society, Inc., 555 N. Kensington Avenue, La Grange Park, Illinois 60526 (United States)

- OSTI Identifier:
- 22105621

- Resource Type:
- Conference

- Resource Relation:
- Conference: PHYSOR 2012: Conference on Advances in Reactor Physics - Linking Research, Industry, and Education, Knoxville, TN (United States), 15-20 Apr 2012; Other Information: Country of input: France; 15 refs.

- Country of Publication:
- United States

- Language:
- English

- Subject:
- 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 22 GENERAL STUDIES OF NUCLEAR REACTORS; ACCELERATION; CONVERGENCE; DECOMPOSITION; FISSION; FOURIER ANALYSIS; NEUTRON FLUX; NEUTRON TRANSPORT; SCATTERING; TRANSPORT THEORY

### Citation Formats

```
Kelley, B. W., and Larsen, E. W.
```*CMFD acceleration of spatial domain-decomposed neutron transport problems*. United States: N. p., 2012.
Web.

```
Kelley, B. W., & Larsen, E. W.
```*CMFD acceleration of spatial domain-decomposed neutron transport problems*. United States.

```
Kelley, B. W., and Larsen, E. W. Sun .
"CMFD acceleration of spatial domain-decomposed neutron transport problems". United States.
```

```
@article{osti_22105621,
```

title = {CMFD acceleration of spatial domain-decomposed neutron transport problems},

author = {Kelley, B. W. and Larsen, E. W.},

abstractNote = {A significant limitation to parallelizing the solution of neutron transport problems is the need for sweeps across the entirety of the problem domain. Angular domain decomposition is common practice, as the equations for each direction are independent aside from their shared scattering/fission source. Accordingly, spatial domain decomposition does not naturally arise in the transport equations and is therefore less frequent in practice. In this paper, we show that a neutron transport domain can be straightforwardly divided into independent, parallelizable sweep regions, globally linked with the standard CMFD method, with an additional update equation. We verify, theoretically (via Fourier analysis) and computationally, that the convergence properties of this method are stable and nominally as rapid as standard CMFD. (authors)},

doi = {},

journal = {},

number = ,

volume = ,

place = {United States},

year = {2012},

month = {7}

}