https://cea.hal.science/cea-02489479Canbakan, A.A.CanbakanEPM - École Polytechnique de MontréalHebert, A.A.HebertEPM - École Polytechnique de MontréalVidal, J.-F.J.-F.VidalCEA-DES (ex-DEN) - CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) - CEA - Commissariat à l'énergie atomique et aux énergies alternativesValidation of a subgroup method for pressurized water reactor fuel assembly modelsHAL CCSD2015Reactor physicsSelf-shieldingLattice schemeAPOLLO2[PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex][PHYS.NUCL] Physics [physics]/Nuclear Theory [nucl-th]amplexor, amplexor2020-02-24 14:48:352020-04-28 11:28:172020-03-13 15:57:15enConference papersapplication/pdf1We are investigating the accuracy of a self-shielding model based on a subgroup method for pressurized water reactor (PWR) fuel assembly models. Until now, APOLLO2 lattice code was using the Sanchez-Coste method based on an $equivalence\ in\ dilution$ with a 281-group Santamarina-Hfaiedh energy mesh (SHEM). Here, we validate a subgroup approach with an improved 361-energy group SHEMat burnup 0 and with isotopic depletion. The aim is to show this new self-shielding technique is more precise than the current one and leads to simpler production computational schemes by avoiding complicated correction algorithms for the mutual resonant self-shielding effects. Compared to a Monte Carlo reference case, the new approach leads to encouraging results in almost every cases. This subgroup technique is proposed as a short-term replacement for the Sanchez-Coste method used in production computational schemes dedicated to the production of multi-parameter cross-section reactor databases.