Evaluation of criticality of FCA XV core series simulating high conversion light water reactor

Sakurai, Takeshi ; Fukushima, Masahiro   

Experimental data obtained in the Fast Critical Assembly (FCA) simulating a High Conversion Light Water Reactor (HCLWR) were evaluated for the criticality of assemblies XV series in the second phase of FCA-HCLWR experiments, primarily using plutonium fuel. Analysis was performed using the nuclear data libraries JENDL-4.0 and JENDL-5 and the Monte Carlo code MVP3, which calculates neutron transport using the continuous energy method. In the evaluation of criticality, a detailed uncertainty assessment was performed, taking into account the effects of uncertainties in the weight and composition of the uranium and plutonium fuel plates and simulated material plates such as moderator in the FCA. The analysis involved detailed simulations of the fuel and lattice tube structures in the FCA. The calculation results for the effective multiplication factor overestimated the experimental results by 0.4% to 0.8% using both JENDL-4.0 and JENDL-5.