Abstract The direct whole core calculation is applied on Cobalt-59 activation calculation. The coupled neutronics, thermal hydraulics and depletion calculation is conducted, where the neutronics is solved by the Monte Carlo code JMCT and the thermal hydraulics is treated with sub-channel method. In the neutronics calculation, the reactor core is pin-by-pin modeled and the cobalt rods are modeled without approximation in geometry. The first reactor cycle is calculated with and without cobalt rods. The power distribution, coolant temperature and boron concentration curve are shown. And the boron concentration curve is compared with the reference value provided by the power plant. The effect of loading cobalt rod on power distributions and critical boron concentration is investigated. With the direct whole core solution, the average specific activity of cobalt rods and their distribution are obtained. In the end, the sensitivity study on number of tracking particles, the coupling strategy and the position of cobalt rods are conducted respectively. And the optimization to enhance the specific activity of cobalt rods is discussed as well.

中文翻译：

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高保真反应堆模拟在Cobalt-59活化计算中的应用

摘要 Cobalt-59活化计算采用直接全核计算。进行了耦合中子学、热工水力和损耗计算，其中中子学采用蒙特卡罗代码JMCT求解，热工水力采用子通道法处理。在中子学计算中，反应堆堆芯是逐针建模的，钴棒的建模没有几何近似。第一个反应堆循环是在有和没有钴棒的情况下计算的。显示了功率分布、冷却剂温度和硼浓度曲线。并将硼浓度曲线与电厂提供的参考值进行比较。研究了负载钴棒对功率分布和临界硼浓度的影响。有了直接的整体核心解决方案，得到钴棒的平均比活度及其分布。最后分别对跟踪粒子数、耦合策略和钴棒位置进行了灵敏度研究。并讨论了提高钴棒比活性的优化方法。