堆内构件径向支承键流致振动载荷研究

CAP1400堆内构件设计过程中,由于涉及系统性和非线性,径向支承键流致振动载荷的预测是一个难点;传统方法针对单部件,采用线性的功率谱密度分析,据此对径向支承键载荷进行非常保守的估计。提出了一种新的计算径向支承键流致振动载荷的简化分析方法,可考虑间隙、刚度、摩擦等非线性效应,从而得到更为准确的结果;建立了CAP1400下部堆内构件的有限元模型,并通过CAP1400堆内构件比例模型动态特性试验结果,验证了该模型的正确性;形成了功率谱密度载荷和时程载荷的转换方法,并验证了其准确性;通过1∶6比例模型试验结果,验证了时程分析方法的准确性。利用CAP1400下降环腔的流致振动载荷,对有限元模型加载进行时程分析,得到了不同间隙状态下堆内构件径向支承键的流致振动载荷。

A study on the FIV load of reactor internals-radial support key

In the design of CAP1400 Reactor Vessel Internals (RVI), because of systemic and non-linear properties, it is difficult to predict the flow induced vibration (FIV) load of Radical Support Key.The traditional way is to get the FIV load of Radical Support Key by over conservative methods, based on the linear PSD analysis for single component.A new simplified method to calculate the FIV load of CAP1400 Reactor Internals-Radial Support Key was proposed in this work, which considers the non-linear effects such as gap, stiffness, and friction, and thus gets more accurate results.A simplified beam model was developed for the CAP1400 lower internals, and has was verified by a CAP1400 RVI 1/6 scale model dynamic property test.The downcomer PSD load was transferred to time history load.The time-history analysis method was verified by scale model test results.The time-history downcomer turbulence load was then applied to the beam model to calculate the FIV load of CAP1400 Radial Support Key in various gap conditions.