Exact weight cancellation in Monte Carlo eigenvalue transport problems.
Phys Rev E
; 104(1-2): 015306, 2021 Jul.
Article
en En
| MEDLINE
| ID: mdl-34412312
ABSTRACT
Random walks are frequently used as a model for very diverse physical phenomena. The Monte Carlo method is a versatile tool for the study of the properties of systems modeled as random walks. Often, each walker is associated with a statistical weight, used in the estimation of observable quantities. Weights are typically assumed to be positive; nonetheless, some applications require the use of positive and negative weights or complex weights and often pose particular challenges with convergence. In this paper we examine such a case from the field of nuclear reactor physics, where the negative particle weights prevent the power iteration algorithm from converging on the sought fundamental eigenstate of the Boltzmann transport equation. We demonstrate how the use of weight cancellation allows convergence on the physical eigenstate. To this end, we develop a method to perform weight cancellation in an exact manner, in three spatial dimensions. The viability of this algorithm is then demonstrated on a reactor physics problem.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Contexto en salud:
1_ASSA2030
Problema de salud:
1_financiamento_saude
Idioma:
En
Revista:
Phys Rev E
Año:
2021
Tipo del documento:
Article
País de afiliación:
Francia