Numerical Simulation Of Fluid - Solid - Coupled Vibration Of Ring Tube Under Internal And Outlet

VIV problem represented by cylindrical blunt body spoiler has always been the focus of academic research, widely used in engineering practice.Fatiguefailure of marine riser caused by VIV, making the marine riser become the most easily damaged parts in the offshore oil and gas exploration and development. In this paper, CFX hasbeen choosed asthe flow field solver and LES as the turbulence model, achieveNumerical simulation of three-dimensional solid two-way fluid-solid coupled with Ansys dynamic response module for large aspect ratio riser model,in multi-physics coupling platform Workbench of commercial CAE software Ansys.Combined with modal analysis,unprecedentedly analyzethe vortex-induced vibration characteristics of large aspect ratio riser model. The main contents of this paper include:The first chapter reviews the current research of marine riser VIV; the secend chapter briefly describes the numerical simulation method and the coupling mechanism VIV involved; the third chapter the results of numerical simulation Comparison with experimental results verify the reliability coupled numerical simulation methods; Chapter IV firstly complete Modal Analysis for the large aspect ratio riser, then riser VIV characteristics coupled simulation and analysisin outflow; in Chapter V, VIV characteristics under the action of internal and external flow riser were simulated and analyzed; the last chapter is the full summaryand outlook of this article.Analyzed by Three-dimensional coupled simulation, it found that the riser vibration characteristics mainly affected by the lift force, with outflows higher Reynolds number, lift variation frequency close to the natural frequency of the structure, the structure resonance amplitude suddenly increase; With lift variation frequency is further increased, the fluid forces stimulate a higher vibrational mode andsmaller riser vibration amplitude. When the riser internal fluid flow, the flow in the riser produce a huge impact for rise’s VIV feature,the internal flow stimulate higher order vibration modes.