A recent benchmarking effort, under the auspices of the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA), has been made to evaluate the current state of modeling and simulation tools available to model fluoride salt-cooled high temperature reactors (FHRs). The FHR benchmarking effort considered in this work consists of several cases evaluating the neutronic parameters of a 2D prismatic FHR fuel assembly model using the participants’ choice of simulation tools. Benchmark participants blindly submitted results for comparison with overall good agreement, except for some which significantly differed on cases utilizing a molybdenum-bearing control rod. Participants utilizing more recently updated explicit isotopic cross sections had consistent results, whereas those using elemental molybdenum cross sections observed reactivity differences on the order of thousands of pcm relative to their peers. Through a series of supporting tests, the authors attribute the differences as being nuclear data driven from using older legacy elemental molybdenum cross sections. Quantitative analysis is conducted on the control rod to identify spectral, reaction rate, and cross section phenomena responsible for the observed differences. Results confirm the observed differences are attributable to the use of elemental cross sections which overestimate the reaction rates in strong resonance channels.

在经济合作与发展组织 (OECD) 核能机构 (NEA) 的主持下，最近开展了一项基准测试工作，以评估可用于模拟氟化物盐冷高温反应堆的建模和模拟工具的现状。 FHR）。在这项工作中考虑的 FHR 基准测试工作包括几个案例，使用参与者选择的模拟工具来评估 2D 棱柱 FHR 燃料组件模型的中子参数。基准参与者盲目地提交结果以与总体良好一致性进行比较，除了一些在使用含钼控制棒的情况下存在显着差异的结果。使用最近更新的显式同位素横截面的参与者有一致的结果，而那些使用元素钼横截面的人观察到与同行相比，反应性差异约为数千 pcm。通过一系列支持测试，作者将差异归因于使用较旧的传统元素钼横截面驱动的核数据。对控制棒进行定量分析，以识别导致观察到的差异的光谱、反应速率和横截面现象。结果证实观察到的差异可归因于元素横截面的使用，它高估了强共振通道中的反应速率。作者将这些差异归因于使用较旧的传统元素钼横截面驱动的核数据。对控制棒进行定量分析，以识别导致观察到的差异的光谱、反应速率和横截面现象。结果证实观察到的差异可归因于元素横截面的使用，它高估了强共振通道中的反应速率。作者将这些差异归因于使用较旧的传统元素钼横截面驱动的核数据。对控制棒进行定量分析，以识别导致观察到的差异的光谱、反应速率和横截面现象。结果证实观察到的差异可归因于元素横截面的使用，它高估了强共振通道中的反应速率。