Evaluating the use of surface source banking to accelerate Monte Carlo transport simulations of far-field particle fluxes

In order to enhance the verifiability and usability of surface source banking as a far-field flux and dose simulation acceleration method for Monte Carlo neutron transport codes, two surface source stationarity criteria were developed and evaluated. Surface sources were considered defined, or an accurate proxy for fission sources in eigenvalue simulations once enough particles have been banked such that these criteria were met. One criterion utilizes multi-dimensional Shannon entropy to indicate the stationarity of the surface source in physical space and energy. The other criterion uses functional expansions to track the stationarity of Legendre coefficients associated with spatially-dependent banked effective neutron reaction rates with different Z materials. The completion of a test case with an OpenMC model of an MK2 TRIGA facility indicated agreement between the two criteria. Effects of oversampling a surface source that met the stationarity criteria, as well as potential limitations of the surface source banking method itself were also examined via the test case.

Name thesis:degree_name

Bachelor

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Nuclear Science and Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2025

Author dc:creator

• Mowery, Eleni T.

Advisor dc:contributor.advisor

• Forget, Benoit

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/159946

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/159946