Abstract The critical power limit for a natural circulation-cooled research reactor core is estimated by utilizing a system analysis code RELAP5/MOD3.3 and an in-house companion program RCPP. The variation range of thermal-hydraulic parameters is found from steady-state and transient simulation results. From literature, potential candidate correlations for critical power estimation were selected and the design limit critical heat flux ratio was evaluated for the chosen correlations based on error statistics. A computational fluid dynamic simulation was carried out to observe the power-equilibrium flow relationship and used to prepare the system code input. To ease a rigorous critical power estimation process, an in-house code was developed to automate batch run and output post-processing of system code. The critical power limit was found for each combination of major operation parameters. A critical power map was generated by merging each power limit value, and the effect of the correlation and core states were studied.

中文翻译：

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自然对流冷却研究堆堆芯的自动临界功率极限估计

摘要 利用系统分析代码RELAP5/MOD3.3和内部配套程序RCPP估算了自然循环冷却研究堆堆芯的临界功率极限。热工水力参数的变化范围是从稳态和瞬态仿真结果中发现的。从文献中，选择了临界功率估计的潜在候选相关性，并根据误差统计评估了所选相关性的设计极限临界热通量比。进行计算流体动力学模拟以观察功率-平衡流动关系并用于准备系统代码输入。为了简化严格的关键功率估计过程，开发了一个内部代码来自动化批处理运行和系统代码的输出后处理。为每个主要操作参数组合找到了临界功率限制。通过合并每个功率极限值生成临界功率图，并研究相关性和核心状态的影响。