Abstract

Previous work presented a set of stylized three-dimensional benchmark problems based on the Oak Ridge National Laboratory (ORNL) preconceptual design of a fluoride-salt-cooled small modular advanced high-temperature reactor, or SmAHTR, with prismatic assemblies fueled by tri-isotropic (TRISO) particles. That previous work created a detailed description of the benchmark problems by closing several outstanding design gaps from the ORNL preconceptual design report, notably by addressing the lack of active control mechanisms, for which control rod “bundles” were implemented.

In this technical note, the creation of two additional stylized benchmark problem sets based on that past work is detailed, offering two new control rod configurations. The fluoride salt, small size, and highly heterogeneous TRISO-fueled pins make these additional benchmark problem sets useful numerical validation references in benchmarking neutronics tools against continuous-energy stochastic Monte Carlo results. Detailed reference results, including the eigenvalue (k_eff) and 1/11th assembly-averaged relative fission density distributions, are provided for both control rod configurations in full-core cases with all control rods withdrawn and all control rods fully inserted. A near-critical core benchmark problem and results are provided for one configuration. The provided results are calculated using the continuous-energy Monte Carlo code MCNP.

摘要

以前的工作提出了一组程式化的三维基准问题，基于橡树岭国家实验室 (ORNL) 的氟盐冷却小型模块化先进高温反应堆 (SmAHTR) 的概念前设计，棱柱组件由三各向同性提供燃料(TRISO) 粒子。先前的工作通过弥补 ORNL 概念前设计报告中的几个突出设计差距，特别是通过解决缺乏主动控制机制的问题，对基准问题进行了详细描述，为此实施了控制棒“束”。

在本技术说明中，详细介绍了基于过去工作创建两个额外的程式化基准问题集，提供两种新的控制棒配置。氟化物盐、小尺寸和高度异质的 TRISO 燃料引脚使这些额外的基准问题集在针对连续能量随机蒙特卡罗结果对中子学工具进行基准测试时设置了有用的数值验证参考。详细的参考结果，包括特征值 (k _eff) 和 1/11 组件平均相对裂变密度分布，提供给全芯情况下的两种控制棒配置，所有控制棒都被撤回，所有控制棒都完全插入。为一种配置提供了近乎关键的核心基准测试问题和结果。提供的结果是使用连续能量蒙特卡罗代码 MCNP 计算的。