Nuclear Energy Technology Sector

For deep-penetration shielding calculations in nuclear reactors, we have developed Marvin, a large-scale parallel deep-penetration shielding analysis code system based on the discrete ordinates method. Marvin supports complex-geometry visual modeling, parallel mesh generation, automatic cross-section processing, criticality calculations, coupled neutron/photon transport calculations, and result visualization.

For the deep-penetration shielding analysis of ex-vessel detectors in a large domestic pool-type sodium-cooled fast reactor, an S16 angular quadrature set and a spatial mesh with 1 billion cells were employed, giving a total of 10¹³ degrees of freedom. Using 9,216 processor cores in parallel, the final calculated results agree with the experimental measurements within a factor of about three (C/E ≲ 3), achieving the highest computational accuracy among similar domestic codes and reaching the international state-of-the-art level.