摘要
管道内液体流动参数随时间变化引起的管道振动,会导致管道共振、连接失效或断裂,对管路系统的稳定和安全运行产生巨大的危害。本文基于泊松流固耦合原理,建立流体动力学模型和管道运动模型,进行流固耦合受力分析和模态分析,研究了有无流固耦合存在时,输流管道振动模态的变化,以及入口速度、压强和壁厚对管道固有频率和阵型的影响。结果显示,考虑流固耦合时,管道的固有频率会增加,壁厚的增加可使管道固有频率减小,流体速度的增加可以减小流固耦合作用对结构的影响,压强增大会使管道固有频率增大。因此,流固耦合作用对管道固有频率的影响不可忽略;适当增加壁厚、减小流体速度、降低压强,可使管道的固有频率减小。高阶模态频率随壁厚、入口速度、压强的变化趋势,要大于低阶模态频率的变化趋势。
The vibration of the pipeline caused by the change of the fluid flow parameters in the pipeline over time could cause resonance,connection failure or breakage of the pipeline,and caused great harm to the stable and safe operation of the pipeline system.Based on the Poisson fluid-structure interaction principle,this paper established a fluid dynamic model and a pipeline motion model,carried out fluid-structure interaction force analysis and modal analysis,and studied the changes in the vibration mode of the fluid-conveying pipeline with or without fluid-structure interaction and the inlet.The influence of speed,pressure and wall thickness on the natural frequency and formation of the pipeline were studied.The results showed that when fluid-structure interaction was considered,the natural frequency of the pipeline would increase.The increase in wall thickness could reduce the natural frequency of the pipeline.The increase of fluid velocity could reduce the influence of fluid-structure interaction on the structure.The increase in pressure would increase the natural frequency of the pipeline.Therefore,the influence of fluid-structureinteraction on the natural frequency of the pipeline could not be ignored.Appropriately increasing the wall thickness,reducing the fluid velocity,and reducing the pressure could reduce the natural frequency of the pipeline.The change trend of high-order modal frequency with wall thickness,inlet velocity and pressure was greater than that of low-order modal frequency.
作者
李玺
LI Xi(School of Mechanical Engineering,Xi’an Shiyou University,Xi’an 710065,China)
出处
《化工技术与开发》
CAS
2021年第1期62-66,共5页
Technology & Development of Chemical Industry
关键词
流固耦合
模态分析
固有频率
fluid-structure interaction
modal analysis
natural frequency
