Abstract In this paper a probabilistic methodology based on core nodalization is proposed to estimate the core power in the presence of xenon oscillation. A time-dependent Monte Carlo neutron transport code named MCSP-NOD is developed for dynamic analysis in arbitrary 3D geometries to simulate xenon oscillations as well as sub-critical condition with feedbacks. The new code is based on the approach adopted in MCNP-NOD which was previously introduced as a tool for core transient analysis using the MCNPX platform. As before, the core is divided into nodes of arbitrary dimensions, and all terms of the transport equation e.g. interaction rates, leakage ratio are estimated using the MC techniques. However, as a new option the concentration of iodine and xenon are also estimated which enables us to predict the oscillatory behavior of reactor power following poison oscillation. These quantities are then employed within the time-dependent neutron transport equation for each node independently to compute the neutron population. Simulations prove the robustness of the method.

中文翻译：

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基于节点离散化模拟带反馈氙振荡的瞬态中子输运方程求解新蒙特卡罗方法

摘要 本文提出了一种基于核心节点化的概率方法来估计存在氙气振荡的核心功率。开发了一种名为 MCSP-NOD 的瞬态蒙特卡罗中子输运代码，用于在任意 3D 几何中进行动态分析，以模拟氙振荡以及具有反馈的亚临界条件。新代码基于 MCNP-NOD 中采用的方法，该方法之前作为使用 MCNPX 平台的核心瞬态分析工具引入。和以前一样，核心被分成任意维度的节点，并且使用 MC 技术估计传输方程的所有项，例如相互作用率、泄漏率。然而，作为一个新的选择，碘和氙的浓度也被估计，这使我们能够预测毒物振荡后反应堆功率的振荡行为。然后在每个节点的瞬态中子输运方程中独立地使用这些量来计算中子种群。仿真证明了该方法的鲁棒性。