A FULL REFERENCE APOLLO3® DETERMINISTIC SCHEME FOR THE JHR MATERIAL TESTING REACTOR

JHR is a new material testing reactor under construction at CEA Cadarache. Its high flux core contains 37 fuel assemblies loaded along concentric rings into alveolus of an aluminum matrix. For the operation reactor, twenty-seven these hovnst hafnium rods in their center while other ones but also beryllium radial reflector can accommodate experimental devices. In order to accurately predict its operating characteristics irradiation performance, recently developed scheme based on APOLLO3 ® platform being which uses sub-group method for spatial self-shielding, 2D and 3D unstructured conform MINARET S n transport solver. A model has been built optimized calculating, lattice step, self-shielded condensed cross sections thanks characteristics. Results are benchmarked against TRIPOLI-4 stochastic reference calculation. more refined mesh gives better results fission rates reactivity compared former APOLLO2 scheme. The classical 2-step calculations use hypothesis infinite configuration, reasonable close not peripheral ones. Hence, approach set up taking account surrounding each assembly. newly 3-step solver than traditional This will be applied modelling heterogeneous configurations incorporating devices enabling burn calculations.