Conception and development of an adaptive energy mesher for multigroup library generation of the transport codes
type: Dataset
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.
landing page: https://theses.hal.science/tel-00678561
keyword: autoprotection
keyword: infoeu-reposemanticsdoctoralthesis
keyword: mathmath-mpmathematics-mathmathematical-physics-math-ph
keyword: mathmath-ocmathematics-mathoptimization-and-control-mathoc
keyword: multigroup-theory
keyword: neutron-transport
keyword: optimisation
keyword: optimization
keyword: probability-tables
keyword: self-shielding
keyword: spiotherengineering-sciences-physicsother
keyword: tables-de-probabilite
keyword: theorie-multigroupe
keyword: theses
keyword: transport-neutronique
issued: 2026-05-24T23:38:42.155880
modified: 2026-05-24T23:38:42.155889
language: fr
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

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