Flow-induced vibration analysis for the secondary support assembly of reactor internal

The secondary support assembly of reactor internals,which is located below the lower support plate,is an important part of the lower internals and is subjected to flow-induced loads.So flow-induced vibration(FIV) analysis is required to be performed so as to ensure the structural integrity of the secondary support assembly.Influences of various flow excitation mechanisms such as random turbulence,quasi-static turbulence,vortex shedding,core barrel motion,etc.on FIV response of the secondary support assembly of 300MW nuclear reactor internals were studied.Structural dynamic loads caused by FIV were calculated by means of combining dynamic responses resulting from various vibration sources of different excitation mechanics via square root of sum of squares(SRSS) method,which provides basis for stress analysis and evaluation of the secondary support assembly.