FLOW-INDUCED VIBRATION AND FLUID STRUCTURE INTERACTION IN NUCLEAR-POWER-PLANT COMPONENTS

This paper gives some subjects of flow-induced vibration (FIV) and fluid-structure interaction (FSI) in nuclear power plant components, especially based on a pressurized water reactor (PWR), a type of light water reactor, and a fast breeder reactor (FBR), promoted as a national project, both of which the author has been experienced with. The flow-induced vibration discussed in this paper also covers cross flow-induced periodic wake shedding, fluid elastic instability and axial flow-induced damping observed in the fuel assembly inside the reactor core, the tube bundle of the steam generator and other components of the reactor, as well as leakage flow-induced vibration. In addition, the discussion on the flow-induced vibration in extended to two-phase flow induced fluid-elastic vibration, random excitation and resultant fretting wear in the U-bend tube bundle of the steam generator, as well as to the problem of vibration induced by fluid pulsation in the component-connecting piping coupled with mechanical vibration of the piping. On the other hand, the fluid-structure interaction discussed here covers hydrodynamic mass-effect, added damping in very closely space reactor internals, as well as sloshing of the free surface of liquid sodium in FBR. © 1990.