%0 Conference Paper %F Oral %T Validation of a subgroup method for pressurized water reactor fuel assembly models %+ École Polytechnique de Montréal (EPM) %+ CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)) %A Canbakan, A. %A Hebert, A. %A Vidal, J.-F. %Z The authors wish to thank AREVA and Electricit ´ e de France (EDF) for their financial contribution in APOLLO2 development and NSERC who supported the academic part of this work. The first author want to thank CEA/SPRC/LEPh who agreed to let him working on APOLLO2, use their clusters and benefit from their researchers who gave prolific advices. %Z CD-ROM, American Nuclear Society, LaGrange Park, IL (2015) %< avec comité de lecture %B ANS MC2015 - Joint International Conference on Mathematics and Computation (M&C), Supercomputing in Nuclear Applications (SNA) and the Monte Carlo Method %C Nashville, United States %8 2015-04-19 %D 2015 %K Reactor physics %K Self-shielding %K Lattice scheme %K APOLLO2 %Z Physics [physics]/Nuclear Experiment [nucl-ex] %Z Physics [physics]/Nuclear Theory [nucl-th]Conference papers %X We 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. %G English %2 https://cea.hal.science/cea-02489479/document %2 https://cea.hal.science/cea-02489479/file/201500000681.pdf %L cea-02489479 %U https://cea.hal.science/cea-02489479 %~ CEA %~ DEN