Development of Subgroup Method 2D Arbitrary Geometry Reso-nance Calculation Code SUGAR

Conventional resonance calculation methods are developed based on the equivalence theory which are only appropriate for the simple regular geometry.It is not capable of dealing resonance calculation for complicated geometries.In this paper,the subgroup resonance calculation method is developed based on the subgroup theory and subgroup neutron transport equation.Resonance calculation is realized for 2D arbi-trary geometry by introducing sophisticated transport solver.Therefore the spatially dependent resonance multi-group cross-sections can be obtained directly by subgroup transport calculation.A computation code SUGAR is developed according to this method and verified by numerical samples.Good accuracy is observed to prove this method and code is very promising for complicate resonance calculation in two dimensional ar-bitrary geometries.