Flow Induced Vibration Response Of The Core Barrel Based On Numerical Simulation

The flow induced vibration of a reactor core barrel was studied in this paper. Based on the numerical simulation method, the vibration characteristics of the core barrel structure in air and water were analyzed. And effects of the reflect layer on the natural vibration characteristics of the core barrel structure were discussed. By considering the action of pulsating flow pressure, of the flow induced vibration responses of the core barrel structure in water were analyzed. The main work and results are as follows:1. The general commercial software ANSYS was applied to establish the 3D entity model of core barrel structure and the appropriate grids of the structure were divided, as well as the reasonable boundary conditions.2. The natural vibration characteristics of the empty core barrel and core barrel containing reflective layer in air and still water were calculated separately. The results show that the structure of the reflective layer in air has a great influence on the second-order mode of the beam type vibration. And the natural vibration frequencies of the structure in still water have significant decreases compared with the results in air.3. Based on the distribution of pulsating pressure of the core barrel obtained by using FLUENT, the vibration responses of the fluid-solid structure were calculated and analyzed. The RMS value distribution diagrams of the surface of the core barrel structure were drawn to analysis the displacements of the responses. The results show that with the restriction at the bottom of the core barrel, the maximum vibrating displacement is at the outlet area.