Conception and development of an adaptive energy mesher for multigroup library generation of the transport codes
type: Dataset
contact point: Organization
  fn: CCSD
keyword: optimization
keyword: neutron-transport
keyword: mathmath-mpmathematics-mathmathematical-physics-math-ph
keyword: autoprotection
keyword: theses
keyword: self-shielding
keyword: spiotherengineering-sciences-physicsother
keyword: infoeu-reposemanticsdoctoralthesis
keyword: transport-neutronique
keyword: mathmath-ocmathematics-mathoptimization-and-control-mathoc
keyword: probability-tables
keyword: optimisation
keyword: multigroup-theory
keyword: tables-de-probabilite
keyword: theorie-multigroupe
landing page: https://theses.hal.science/tel-00678561
description: The deterministic transport codes solve the stationary Boltzmann equation in a discretized energy formalism called multigroup. The trans- formation of continuous data in a multigroup form is obtained by avera- ging the highly variable cross sections of the resonant isotopes with the solution of the self-shielding models and the remaining ones with the co- arse energy spectrum of the reactor type. So far the error of such an ap- proach could only be evaluated retrospectively. To remedy this, we stu- died in this thesis a set of methods to control a priori the accuracy and the cost of the multigroup transport computation. The energy mesh optimisation is achieved using a two step process : the creation of a reference mesh and its optimized condensation. In the ﬁrst stage, by reﬁning locally and globally the energy mesh, we seek, on a ﬁne energy mesh with subgroup self-shielding, a solution equivalent to a reference solver (Monte Carlo or pointwise deterministic solver). In the second step, once ﬁxed the number of groups, depending on the accep- table computational cost, and chosen the most appropriate self-shielding models to the reactor type, we look for the best bounds of the reference mesh minimizing reaction rate errors by the particle swarm optimization algorithm. This new approach allowed to deﬁne new meshes for fast reactors as accurate as the currently used ones, but with fewer groups.
issued: 2026-05-24T23:38:42.155880
language: fr
modified: 2026-05-24T23:38:42.155889

Conception and development of an adaptive energy mesher for multigroup library generation of the transport codes
type: Distribution
access URL: https://theses.hal.science/tel-00678561
format: HTML
issued: 2026-05-24T23:38:42.175446
modified: 2026-05-24T23:38:42.093527

test_moissonnage_selune
type: Agent