Towards 2D reference deterministic calculations in support of industrial model verification and advanced reflector modeling setup

Current industrial codes use efficient, simplified one-dimensional models to compute macroscopic reflector cross-sections (XS) for core calculations. For predicting the core response when heavy radial reflectors are employed, such as in the case of the VVER-1000 reactor type, two-dimensional radial reflector models may be developed and investigated. The present work supports the investigations about 2D reflector modeling setup using the new generation deterministic French code APOLLO3®, providing a Python library wrapping the ALAMOS mesh generator API to quickly generate 2D reflector geometry and meshes for lattice calculations. The proposed tool is intended to be integrated into the NEMESI platform, the multiparameter lattice generator prototype developed within the H2020 CAMIVVER project and oriented towards the industrialization of the APOLLO3® code. In the paper, the application of the library to three cases representative of and western PWR design is presented. Two configurations defined in the CAMIVVER project have VVER been considered: the KAIST-like core, a PWR-based case with a heavy reflector, and the Kozloduy-6 mini-core, representing a VVER. A third configuration dedicated to showing the applicability of the method to a full-scale core with heavy reflector is also presented.