Simulation optimization and design of eddy current detection probe for the oxidation film thickness of zirconium alloy shell

Abstract Nuclear fuel components are running in extremely harsh environments such as high radioactive, high temperature and deep water for a long time, and it is easy to produce oxide films on the surface of the fuel rod, which affects the operation of fuel components. Therefore, obtaining the oxide film data on the fuel rod can provide data support for analyzing fuel corrosion performance and the operating status in the heap. The simulation model of the thickness detection of the oxide film on the surface of zirconium alloy surface was established using the COMSOL software. The overall structure size parameters and incentive parameters of the designed probe was optimized and analyzed, and the corresponding relationship between its coil impedance amplitude and phase changes and the influencing factors was analyzed. The simulation results showed that the impact of the detection sensitivity in the coil parameters from high to low was turning, middle diameter, height, and width. The simulation results were used to design a new type of oxide film measurement probe, the oxide film measurement system was used to carry out non-metallic membrane tests on the surface of zirconium alloy plate. The test results showed that the detection precision of the oxide film probe was high, and the measurement deviation was less than 5 μm.