Abstract In this study, analysis of the complete operational history of the “Jožef Stefan” Institute (JSI) TRIGA reactor was performed. Reactor power changes, core configurations and weekly excess reactivity measurements were analysed to obtain the needed data for fuel burnup calculations. More than 50 years of reactor operation was simulated using deterministic code TRIGLAV and stochastic code Serpent-2. The calculated core reactivities are in good agreement compared with the excess reactivity measurements. Code-to-code comparison is presented. Clear agreement is observed when comparing changes in core excess reactivity, and discrepancies are observed in the comparison of individual fuel element burnup and its isotopic composition. The Serpent-2 results are in better agreement with the measurements compared to the TRIGLAV code; nevertheless, a conclusion can be made that the TRIGLAV code is viable for TRIGA fuel management and burnup analysis. A three-dimensional (3D) burnup study was conducted, where individual fuel elements were further divided into multiple angular and axial depletion zones. Notable burnup effects were observed, and an explanation using surrounding water distance is presented.

中文翻译：

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TRIGA Mark II 研究堆燃料的计算燃耗分析

摘要 在这项研究中，对“Jožef Stefan”研究所 (JSI) TRIGA 反应堆的完整运行历史进行了分析。分析反应堆功率变化、堆芯配置和每周过量反应性测量，以获得燃料燃烧计算所需的数据。使用确定性代码 TRIGLAV 和随机代码 Serpent-2 模拟了 50 多年的反应堆运行。与过量反应性测量值相比，计算的核心反应性非常一致。提供了代码到代码的比较。在比较堆芯过量反应性的变化时观察到明显的一致性，在单个燃料元件燃耗及其同位素组成的比较中观察到差异。与 TRIGLAV 代码相比，Serpent-2 的结果更符合测量结果；尽管如此，可以得出结论，TRIGLAV 代码对于 TRIGA 燃料管理和燃耗分析是可行的。进行了三维 (3D) 燃耗研究，其中单个燃料元件被进一步划分为多个角度和轴向耗尽区。观察到显着的燃耗效应，并提出了使用周围水域距离的解释。