Vibration control of a nuclear fuel rod maneuvering under water

This paper addresses the vibration control problem of a fuel transport system (FTS) in a nuclear power plant. The FTS transports the fuel rods in the nuclear reactor to desired locations within the fuel building. The fuel rods must be transported under water to avoid radiation leaks into the environment. It has been observed that a quick maneuver of the trolley can cause vibrations that can damage the structure of the fuel rods, due to the hydrodynamic force exerted by the surrounding fluid. In this study, a distributed parameter model of the FTS, using the extended Hamilton´s principle, is developed. The developed model is verified with experiments. A velocity command is designed, as an open-loop control, to transport the fuel rods in quick time to the target locations with minimal vibrations. The residual vibrations of the fuel rod are controlled while considering the effects of the hydrodynamic force imposed by the surrounding water. Simulation and experimental results show that the proposed velocity command transports the fuel rods to the target location quickly resulting in a significant decrease in the rod´s vibrations.