Research On Suppression Of The Flow-induced Vibration Of A Circular Cylinder By Traveling Wave Wall Control Method

Cylinder-like structures can be found in the designs for offshore structures,buildings,chimneys,power lines,and cables,in both air-and water-flow.Fluid flow over a circular cylinder is one of the classical problems of fluid mechanics.in many of these engineering applications,vortex shedding of flow around one cylinder or cylinder group is responsible for problems with flow-induced vibration,which can provide a major source of instability and fatigue damage to engineering structures.So,it is necessary to eliminate vortex and suppress flow-induced vibration and the associated fluid-structure interaction in order to improve the design of such engineering structures.In this paper,both CFD numerical simulation and wind tunnel were combined: dynamic mesh in Fluent was employed to generate Traveling Wave Wall(TWW)on the rear section of cylinder;a new cylinder-TWW system was developed,eliminating the oscillating vortex by moving waves,in order to eliminate fluid-induced vibration of a circular cylinder.The main research points are:The numerical simulation of fluid flow over a fixed cylinder at high Reynolds number was accomplished.The aerodynamic force coefficients obtained was compared with the experimental values,to verify reasonability and reliability in constructed grids as well as solution method,being the basis of following fluid-structure interaction computation.Effectiveness under different TWW parameters in simulation will be accomplished,studying how parameters influenced control effects.Propagating direction,wave amplitude,wave number and wave velocity were discussed for their effects on aerodynamic force.Evaluate control effectiveness by characteristic values of aerodynamic force,analyze from that we can get optimal parameter combination.Using the optimal parameter combination,carry out spring-supported Cylinder-TWW system simulation,and then CFD numerical simulation of bi-directional fluid-structure interaction effect between cylinder with TWW and flow field.Study the obtained time-history and characteristic value of aerodynamic and displacement response.Analyze control effect,and then derivate transient aerodynamic force TWW caused.Develop a Cylinder-TWW system,accomplish a wind tunnel experiment of fluid flow over a fixed cylinder or Cylinder-TWW.Use PIV to measure wake flow field of Cylinder-TWW system.By contrasting standard cylinder,static Cylinder-TWW and moving Cylinder-TWW with different wave velocities,analyze control effect under different inflow velocity as well as diff erent wave velocity.