Abstract The steady-state fuel behavior prediction code FRAPCON has been coupled with the Monte Carlo code MCS to accomplish fuel performance analysis capability. The Monte Carlo based multi-physics coupling analysis for large-scale light water reactors (LWRs) with high fidelity has mostly focused on the inner coupling of the Monte Carlo neutronics analysis code and the thermal–hydraulics code. However, there are still some issues that cannot be considered precisely when predicting fuel thermal conductivity, and the gap thermal conductance between fuel pellets and cladding with the increase of burnup. Therefore, the FRAPCON has been chosen in this paper to be coupled with the MCS code to increase the accuracy of fuel temperature calculations and the corresponding fuel temperature feedback. A fixed-point iteration scheme is adopted for the coupling interface, which has been verified by a single rod case. In addition, the paper also depicts the application of the MCS/FRAPCON coupling system to the BEAVRS quarter core benchmark, by comparison with MCS internal one-dimension T/H solver — TH1D. The results clearly explain the necessity for considering the fuel performance in multi-physics coupling analysis and demonstrate the capability of the MCS/FRAPCON coupling system.

中文翻译：

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FRAPCON 耦合用于蒙特卡罗代码 MCS 中的燃料性能分析

摘要 稳态燃料行为预测程序FRAPCON 与蒙特卡罗程序MCS 相结合，实现燃料性能分析能力。基于蒙特卡罗的高保真大型轻水反应堆 (LWR) 多物理场耦合分析主要集中在蒙特卡罗中子学分析代码和热工水力代码的内部耦合上。然而，在预测燃料热导率以及燃料芯块与包壳之间的间隙热导率随燃耗增加时，仍存在一些不能准确考虑的问题。因此，本文选择FRAPCON 与MCS 代码耦合，以提高燃油温度计算和相应燃油温度反馈的准确性。耦合界面采用定点迭代方案，已通过单杆案例验证。此外，本文还通过与MCS内部一维T/H求解器TH1D的对比，描述了MCS/FRAPCON耦合系统在BEAVRS四分之一核基准测试中的应用。结果清楚地解释了在多物理场耦合分析中考虑燃料性能的必要性，并证明了 MCS/FRAPCON 耦合系统的能力。