BENCHMARKING OF THE GRAPHITE AND FLUORIDE INSERTIONS IN LR-0 REACTOR

摘要

Graphite and selected fluoride salts have their place in historic, as well as in most advanced nuclear reactors. Integral benchmarking of materials used in nuclear technology is very important for validation of calculation codes used at advanced reactor modelling. Discovered discrepancies can also point at inaccurate description of nuclear data. Benchmark experiments have been carried out in zero power light water reactor, LR-0, which is suited for these tasks thanks to the well-defined criticality. Criticality and neutron spectrum in graphite and fluoride salt has been benchmarked in experimental phase. The results of critical benchmark for graphite are showing good coincidence with calculation in ENDF/B-Ⅶ.0 nuclear library, however discrepancies exceeding 3σ interval of uncertainties have been demonstrated with fluoride salt. Large discrepancies are apparent from C/E-1 comparison of neutron spectrum in fluoride salt. These discrepancies are likely caused by improper description of ~(19)F.