Abstract During irradiation, the fuel-cladding interface of a nuclear fuel rod can experience significant mechanical and chemical interaction. In-situ measurement of the radial deformation of the cladding can quantify the extent of this interaction and the state of the cladding. Existing capabilities to perform in-pile diameter measurements are limited by required contact and an intrusive presence of a device near to a specimen. To overcome these limitations, researchers have developed and evaluated an electrical impedance based diameter gauge using a benchtop system. The sensor consists of an electrically conductive concentric ring around the fuel cladding such that the electrical impedance between the ring and cladding is measured. The cladding diameter is determined through a measurement of the electrical impedance between the electrodes with a known ring electrode diameter. Analytic and three-dimensional finite element analyses (FEA) were used to quantify the measurement sensitivity, uncertainty, and off-design conditions. The experimental sensor measured diameters with less than 20 μm of error, and had a measurement resolution of less than1 μm for diameters ranging from 9.5 to 9.6 mm. The uncertainty analysis for the experimental setup estimated an uncertainty of 20 μm, consistent with the experimentally measured results.

中文翻译：

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用于堆内燃料变形测量的基于阻抗的直径计

摘要 在辐照过程中，核燃料棒的燃料包壳界面会发生显着的机械和化学相互作用。包层径向变形的原位测量可以量化这种相互作用的程度和包层的状态。执行堆内直径测量的现有能力受到所需接触和靠近样品的设备的侵入性存在的限制。为了克服这些限制，研究人员使用台式系统开发并评估了基于电阻抗的直径计。该传感器由围绕燃料包壳的导电同心环组成，以便测量环和包壳之间的电阻抗。通过测量具有已知环形电极直径的电极之间的电阻抗来确定包层直径。解析和三维有限元分析 (FEA) 用于量化测量灵敏度、不确定性和非设计条件。实验传感器测量直径的误差小于 20 μm，对于 9.5 至 9.6 mm 的直径范围，测量分辨率小于 1 μm。实验装置的不确定性分析估计的不确定性为 20 μm，与实验测量结果一致。实验传感器测量直径的误差小于 20 μm，对于 9.5 至 9.6 mm 的直径范围，测量分辨率小于 1 μm。实验装置的不确定性分析估计的不确定性为 20 μm，与实验测量结果一致。实验传感器测量直径的误差小于 20 μm，对于 9.5 至 9.6 mm 的直径范围，测量分辨率小于 1 μm。实验装置的不确定性分析估计的不确定性为 20 μm，与实验测量结果一致。