Nonlinear acceleration methods for even-parity neutron transport

Convergence acceleration methods for even-parity transport are being developed that have the potential to speed up transport calculations and provide a natural avenue for an implicitly coupled multiphysics code. An investigation was performed into the acceleration properties of the introduction of a nonlinear quasi-diffusion-like tensor in linear and nonlinear solution schemes. Although poor numerical properties prohibit the direct matrix solution of this reduced system, using it as a preconditioner for the conjugate gradients method proves highly efficient and effective and using it directly in a nonlinear solution scheme proves practical but costly. The results for the linear and nonlinear cases serve as the basis for further research into the application in a full three-dimensional spherical-harmonics even-parity transport code. Once moved into the nonlinear solution scheme, the implicit coupling of the convergence accelerated transport method into codes for other physics can be done seamlessly, providing an efficient, fully implicitly coupled multiphysics code with high order transport.

Name thesis:degree_name

Nuclear Engineering

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Nuclear Engineering

Year

2010

Author dc:creator

• Martin, William

Contributors dc:contributor

• de Oliveira, Cassiano
• Prinja, Anil
• Coutsias, Evangelos

Language dc:language

English

Identifier

https://digitalrepository.unm.edu/ne_etds/24

OAI identifier oai:identifier

oai:digitalrepository.unm.edu:ne_etds-1023