Vortex mode of vortex-induced vibration with a 2-dimensional elastic circular cylinder

A numerical simulation of vortex-induced vibration of a 2-dimensional elastic circular cylinder with one degree of freedom under the uniform flow was calculated when Reynolds is 200.2-dimensional incompressible Navier-Stokes equations were solved with the space-time finite element method,the equation of the cylinder motion was solved with the new explicit integral method and the mesh renew was achieved by the spring moving mesh technology.Considering vortex-induced vibration with the low reduced damping parameter,the variety trend of the lift coefficient,the drag coefficient,the displacement of cylinder was analyzed under different oscillating frequencies of cylinder.The phenomena of lock-in,beat and phaseswitch were captured successfully.The evolution of vortex shedding from the cylinder with time is discussed,the new vortex mode of 2P+2S is observed.When the amplitude of cylinder is the maximum,2S,2P+2S and 2P mode may be appeared in the different position of the wake.