实时RPV中子剂量测量的共轭探测器响应函数方法研究

An Adjoint Detector Response Function Method for Real-Time RPV Neutron Dosimetry

摘要: 精确的反应堆压力容器辐照评估，对延长反应堆寿命和核电站的长期运行至关重要。每个反应堆压力容器都有其独特的辐照历史，因此需要进行大量的输运计算。传统方法效率低下，无法针对每种运行条件快速重新计算。本文建立了一个实时探测器响应计算框架，称为共轭探测器响应函数(Adjoint Detector Response Function, ADRF)方法。ADRF系数通过结合首次碰撞源(First-Collision Source, FCS)技术进行的一系列共轭计算预先求得。这些系数与ARES系统中的中子源分布进行线性组合。结果表明，ADRF方法在将计算时间缩短几个数量级的同时，其模拟结果与完整输运计算结果的偏差控制在1%左右。该方法为反应堆压力容器的实时剂量测量提供了高保真度的替代方案，为下一代在线监测系统的开发奠定了基础。

Abstract: Accurate irradiation assessment of the reactor pressure vessel (RPV) is critical for reactor life extension and the long-term operation of nuclear power plants. Each RPV possesses a unique irradiation history, necessitating a multitude of transport calculations. The inefficiency of traditional methods prevents rapid recalculation for every operating conditions. This paper establishes a real-time detector response calculation framework, referred to as Adjoint Detector Response Function (ADRF) methodology. The ADRF coefficients are pre-calculated through a series of adjoint calculations with the First-Collision Source (FCS) technique. These coefficients are linearly combined with neutron source distributions from the ARES system. Results demonstrate that the ADRF method reproduces full transport results within 2%, while reducing computational time by several orders of magnitude. The methodology provides a high-fidelity alternative for real-time RPV dosimetry, enabling next generation online monitoring systems.