Underwater fuel assembly deformation measurement with multisensor dual-line structured light

The fuel assembly is the core component of the nuclear energy system, and its excessive deformation will affect the normal insertion of the fuel rod and endanger safe operation of the reactor. In this paper, we present an underwater fuel assembly deformation measurement system based on 10 sets of visual measurement units. Benefitting from the waterproof design, the shielding-radiation design, the reflective structure design, the dual-optical line laser triangulation principle, and the underwater multilayer refractive geometry, the measurement system has shorter measurement time, higher measurement accuracy, and better environmental adaptability. Through the underwater field measurement and verification of the standard rod and fuel assembly, the bow deformation measurement accuracy of the measurement system is better than 0.3 mm, and the twist deformation measurement accuracy of the system is better than 0.15 degrees. The proposed method allows transient and high-precision measurement in a certain irradiation dose and certain depth water, which provides a strong guarantee for measurement of fuel assembly deformation parameters in deep water and high radiation. (C) 2021 Optical Society of America

Automated summary

This paper presents an underwater fuel assembly deformation measurement system based on visual measurement units, which features a waterproof and radiation-shielding design, reflective structure design, dual-optical line laser triangulation principle, and underwater multilayer refractive geometry. Through field measurement and verification, the system achieves high measurement accuracy for bow and twist deformation, providing a strong guarantee for measuring fuel assembly deformation parameters in deep water and high radiation environments.