基于ANSYS的气液两相流海洋立管流固耦合振动分析

运用ANSYS软件对气液两相流海洋立管进行了单、双向流固耦合振动分析,并将单、双向流固耦合进行了对比分析,同时考虑了立管支承方式、流体边界条件对立管振动的影响,最后提出了立管减振措施。结果表明:立管变形最大处发生在立管中间处,最大应力发生在立管的入口和出口处附件的上下部;双向耦合作用下立管最大等效应力和最大变形量均小于单向耦合;随着立管约束数量的增加,立管的变形量和等效应力变小;随气相速度增大时,立管位移减小,相反,随液相流速的增加,立管位移增大,随截面含气率的减小,立管位移增大。分析结果对海洋立管的优化设计和运行的可靠性提供了重要的理论意义。

Fluid-solid Coupling Vibration Analysis of Gas-liquid Two-phase Flow Marine Vertical Riser Based on ANSYS

Interaction between fluid and elastomer in marine vertical riser is main cause of vertical riser vibration, which has a direct impact on the dynamic characteristics of vertical riser. In this paper, ANSYS software is used to analyze one-way and two-way fluid-solid coupling vibration of gas-liquid two-phase flow marine vertical riser, and results are compared and analyzed. Vertical riser support mode and fluid boundary condition are taken into account. Vibration reduction measures with vertical riser are proposed in the end. The results show that the maximum deformation of vertical riser occurs in the middle of vertical riser, and the maximum equivalent stress occurs at the upper and lower portions in the vicinity of inlet and outlet. The maximum equivalent stress and the maximum deformation of vertical riser under the two-way fluid-solid coupling interaction are smaller than the one-way fluid-solid coupling interaction. As the number of vertical riser constraints increases, the deformation and equivalent stress of vertical riser become smaller; as the gas phase velocity increases, vertical riser displacement decreases. Conversely, as the liquid flow velocity increases, vertical riser displacement increases. As the gas fraction of the section decreases, vertical riser displacement increases. The analysis results provide important theoretical significance for the optimal design and operational reliability of marine vertical risers.