堆内构件防断支承组件流致振动分析

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

堆内构件下部防断支承组件是反应堆堆内构件中堆芯下部支承结构的一个重要组成部分,它位于堆芯吊篮组件的下面,并处于堆内流场中复杂的流体交混区,为保持防断组件的结构完整性,必须对其进行流致振动分析。以某300MW反应堆堆内构件防断组件为研究对象,研究了随机湍动力、拟静态湍动力、旋涡脱落、吊篮运动等流体激励机理对防断组件流致振动的影响。用SRSS法对各激励机理作用下防断组件的各阶动态反应进行组合后,计算了由于流致振动引起的结构动态载荷,为防断组件的应力分析与评定提供了依据。

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.