Analysis of Self-excited Sloshing Caused by the Fluid Discharge over the Flexible Weir Including Nonlinearity

含非线性柔性堰排液引起的自激晃动分析

基本信息

批准号：
07650275
负责人：
KANEKO Shigehiko
金额：
$ 1.47万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650275/
关键词：
Flow Induced Vibration Sloshing Self-excited Vibration Non-linear Vibration Stability Overflow Shell Vibration Fast Breeder Reactor シェル

项目摘要

Two rypes of self-excited vibrations of a cylindrical shell caused by the fluid discharge over the flexible weir were observed in French demonstration fast breeder reactor, Super Phoenix-1 during test operations. The first type is a sloshing coupled vibration and the latter is so called a fluidelastic vibration.In this study, an analytical model for the sloshing coupled vibration as observed in Super-Phoenix-ILMFBR is proposed. This fluid-structure system is constituted by the flexible weir and adjoining fluid plenums and the fluid is discharged from the upstream plenum to the downstream plenum over the flexible weir. The characteristic equation of the system is derived for the case in which the weir vibrates at the frequency of the downstream sloshing.In this research project, special attentions were made with higher mode sloshing coupled vibrations with the case of a rectangular flexible plate and with the case of two flexible cylindrical weirs. The effects of the fluid level difference between the upstream and the downstream plenum and weir rigidity are examined both theoretically and experimentally and the mechanism for instability is discussed in detail. As a result, it was found that the effects of discharge flow rate and the liquid height difference between the upper and lower tank on the higher mode instability can also be described by the proposed analytical model.

法国示范快中子增殖堆“超级凤凰一号”在试运行期间观察到两种由柔性堰上流体排放引起的圆柱壳自激振动。第一种类型是晃动耦合振动，后者称为流体弹性振动。在本研究中，提出了在 Super-Phoenix-ILMFBR 中观察到的晃动耦合振动的分析模型。该流体结构系统由柔性堰和相邻的流体静室构成，并且流体通过柔性堰从上游静室排出至下游静室。针对堰以下游晃动频率振动的情况推导了系统的特征方程。在本研究项目中，特别关注矩形柔性板情况下的高模态晃荡耦合振动和两个柔性圆柱形堰的情况。从理论上和实验上研究了上游和下游静压室之间的液位差和堰刚度的影响，并详细讨论了不稳定的机制。结果发现，排放流量和上下罐之间的液体高度差对高模态不稳定性的影响也可以通过所提出的解析模型来描述。