弯曲输流管道流固耦合动力特性分析

管道中流体和弹性体之间的相互作用是引起管道振动的主要原因,这种流固耦合作用对管道动力特性有直接影响。以流固耦合理论为基础,对脉动压力作用下的弯曲输流管道建立流体动力学模型及固体运动模型,在ANSYS Workbench中分别进行双向流固耦合受力分析、单双向流固耦合对比分析和模态分析,并考虑脉动压力,壁厚和管径等参数的影响。结果表明,弯管最大应力发生在入口和出口附近上下部,最大变形发生在转角及中间处;双向耦合作用下弯管最大等效应力与最大变形量均大于单向耦合;双向耦合作用下弯管固有频率明显降低,且固有频率随壁厚和管径的增大呈非线性增长。

AnalysisofDynamicCharacteristicsofFluid-structure InteractioninCurvedInfusionPipelines

The interaction between fluid and elastic solid in fluid-filled pipes plays a key role in pipeline vibration. The fluid-structure coupling effect has a direct impact on the pipe’s dynamic characteristics. In this paper, based on the theory of fluid-structure coupling, the fluid dynamics model and solid motion model were established for a crooked liquid-filled pipe which were impacted by the fluctuating pressure, the force analysis of Two-way fluid-structure interaction and modal analysis were conducted in ANSYS Workbench software, and then the impact of fluctuating pressure, wall thickness and diameter were also take into account. The results showed that the maximum stress occurred at the upper and lower portions in the vicinity of inlet and outlet, and the maximum deformation occurred at corners and the middle of the pipe. And, next, the maximum equivalent stress and maximum deformation of pipe under the two-way fluid-structure interaction were greater than the one-way. Lastly, The natural frequency of the bending infusion pipes under the two-way fluid-structure interaction decreased significantly, and the natural frequency of the pipe presented non-linear growth with the increasing of wall thickness and diameter.