Uncertainty analysis of temperature effect on reactivity in very high temperature reactor critical assembly and establishment of biases for benchmark models

Kitamura, Yasunori; Eguchi, Yuta 

A series of integral reactor physics experiments conducted at the Very High Temperature Reactor Critical Assembly (VHTRC) was analyzed and assembled into a benchmark through an extensive peer-review process under the International Reactor Physics Experiment Evaluation Project (IRPhEP). This benchmark provides the experimental data with respect to criticalities of 7 core configurations and temperature effect on reactivity up to 200C with explicit experimental uncertainties newly evaluated. It further presents the benchmark models and corresponding values with proper simplification, so that it can be utilized by reactor designers for validating their analytical tools employed to design next-generation reactors and for establishing the safety basis for operation of those reactors.