Leakage-corrected fast reactor assembly calculation with Monte-Carlo code and its validation methodology
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摘要: 一种基于B1均匀化方程的泄漏修正模型在连续能量蒙特卡罗程序TRIPOLI4中得以实现并且用于制作少群截面参数。此蒙卡泄漏修正模型通过在连续能量的蒙卡模拟以及求解B1均匀化方程之间迭代,最终得到蒙卡模拟下的临界状态。通过此方法得到的少群截面参数较其他蒙卡以及确定论方法有两点显著优势:用于求解B1均匀化方程的少群常数是用通过临界状态的通量谱得到的;考虑了泄漏效应的蒙卡模拟可以更真实地反映组件计算时的能谱状态。为验证此泄漏修正模型,一个由连续能量的TRIPOLI4模拟而得到的数值临界实验被用于分析与比较。通过与其他蒙卡程序SERPENT以及确定论程序ECCO进行结果对比,可证明此B1泄漏修正方法能够给出更精确的用于堆芯计算的少群截面参数。Abstract: A leakage model based on B1 homogeneous equations has been implemented in continuous-energy Monte Carlo code TRIPOLI4. This leakage model algorithm iterates between the point-wise Monte Carlo simulation and a B1 homogeneous equation solver till reaching a final critical state in Monte Carlo simulation. The two advantages of our leakage model compared with the others are: we use critical flux spectrum to generate the multi-group constants for solving the B1 homogeneous equation; the leakage coefficients calculated are considered in point-wise Monte Carlo simulation. This leakage model is validated by a pre-designed numerical experiment simulated with continuous-energy TRIPOLI4 and the results obtained by this leakage model are proved to be more accurate by comparison with those from SERPENT leakage model and deterministic leakage model in ECCO code.
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Key words:
- leakage model /
- critical buckling /
- cross section
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表 1 临界曲率比较结果
Table 1. Comparison of critical buckling values
B2/(10-3cm-2) relative diff/% numerical curve 2.854 - TRIPOLI4 2.823 -1.09 SERPENT 2.807 -1.65 ECCO 2.747 -3.75 -
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