Axial-Flow-Induced Vibration Studies on Cantilever Rods for Nuclear Reactor Applications: A Summary of Recent Research

Abstract

Abstract:  With over 400 nuclear power reactors currently operating worldwide, 66 units under construction, 85 more in the planning stage and an additional 344 reactor proposed, nuclear power plays a key role in the global low-carbon electricity production, and will remain a key player in the years to come. A frequent cause of unplanned and costly outages in water-cooled nuclear power plants is the premature failure of the fuel rods due to excessive flow-induced vibration in the reactor core. Turbulence and unsteadiness in the coolant water flowing through the reactor core can cause excessive vibration of the fuel rods, which in turn can result in fretting wear that eventually leads to the fuel rod cladding perforation and subsequent failure. The economic burden of unplanned reactor outages has motivated extensive research into flow-induced vibration. This technical note provides a brief summary of recent research on flow-induced vibration of cantilever rod systems, which are paradigmatic test configurations that have been instrumental to advance the fundamental physical understanding of axial-flow-induced vibration problems for nuclear reactor systems. The summary covers both experimental and numerical studies, and includes a description of the non-contact measuring techniques employed to track the vibration of the cantilever rod.

Keywords: Optical tracking, Hall-effect-based position tracking, Particle image velocimetry (PIV), Fluid-structure interaction (FSI); Fretting wear