Abstract A 4-step data analytic methodology has been devised for the purpose of inferring the distribution of power in a reactor core, based on the response of an array of optical fiber based gamma thermometers (OFBGTs). This data analytic methodology is crucial for the development of a system of OFBGTs for the purpose of calibrating local power range monitors in boiling water reactors. Such a system would be an improvement to the present calibration system in boiling water reactors, in terms of safety, efficiency, and permanence. The first step of this methodology is to establish an energy balance method. In this method, one uses MCNP to determine response functions, which allow one to convert from gamma thermometer response to power. The gamma thermometers and the reactor core are segmented, such that each gamma thermometer segment provides an estimate of power for each reactor core segment. The estimates of power for the reactor core segments (hereafter referred to as fuel assembly segments) are calculated based on the measured response of the gamma thermometers. The second step of the methodology is to employ a weighting scheme to combine the estimates of the power of the various fuel assembly segments, based on the response of the various OFGBT segments and the incremental dose rates of the various fuel assembly segments to the OFBGT segments. The third step is to iteratively calculate the estimates of the power of the fuel assembly segments, until a convergence criterion is met, which indicates that the calculation has converged. The fourth and final step of the methodology is to estimate the uncertainty of the power for each fuel assembly segment. The mathematical basis for this step is not the focus of this paper. We have used a 3-D homogeneous reactor model to demonstrate the data analytic methodology; and have found that the data analytic methodology operates as intended.

中文翻译：

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从基于光纤的伽马温度计阵列推断反应堆堆芯功率分布的方法

摘要 为了根据基于光纤的伽马温度计 (OFBGT) 阵列的响应来推断反应堆堆芯中的功率分布，设计了 4 步数据分析方法。这种数据分析方法对于开发用于校准沸水反应堆本地功率范围监测器的 OFBGT 系统至关重要。在安全性、效率和持久性方面，这样的系统将是对沸水反应堆中现有校准系统的改进。该方法论的第一步是建立能量平衡方法。在这种方法中，人们使用 MCNP 来确定响应函数，从而可以将伽马温度计响应转换为功率。伽马温度计和反应堆堆芯是分段的，以便每个伽马温度计段提供每个反应堆堆芯段的功率估计。反应堆堆芯段（以下称为燃料组件段）的功率估计值是根据伽马温度计的测量响应计算得出的。该方法的第二步是采用加权方案，根据各个 OFGBT 段的响应和各个燃料组件段对 OFBGT 段的增量剂量率，结合对各个燃料组件段的功率估计。 . 第三步是迭代计算燃料组件段的功率估计，直到满足收敛标准，这表明计算已经收敛。该方法的第四步也是最后一步是估计每个燃料组件段的功率不确定性。这一步的数学基础不是本文的重点。我们使用 3-D 均质反应器模型来演示数据分析方法；并发现数据分析方法按预期运行。