Design of NECL subgroup data module and arbitrary geometry resonance calculation code in neutronics evaluation comprehensive package

A multi-group data module and a subgroup resonance calculation code were designed for Neutronics Evaluation Comprehensive Package based on subgroup method in this paper. A self-advanced 2D transport module called matrix MOC was employed as solver in subgroup resonance calculation module. Finally, a series of resonance benchmarks were calculated by MCNP and subgroup code respectively, and the k_inf and macro cross section of ²³⁵U and ²³⁸U by MCNP and subgroup code were compared. The results show that the subgroup code has enough accuracy and adaptability for arbitrary geometries and it's suitable for 2D arbitrary resonance calculation. (authors)