Interactions of vortex-induced vibrations of a circular cylinder and a steady approach flow at a Reynolds number of 13,000

The interactions of vortex-induced vibrations of a circular cylinder and a steady approach flow at a Reynolds number of 13,000 have been studied by numerical solutions of the stream-function/vorticity formulation of the two-dimensional incompressible Navier-Stokes equations with a large eddy simulation for the turbulence in the wake. The calculated results are in good agreement with available experimental data. It is shown that lock-on occurs between 0.82fso and 1.31fso, where fso is the vortex shedding frequency of a fixed circular cylinder, and can induce cylinder vibrations with a maximum amplitude of 0.31 × diameter of the cylinder. Material damping not only reduces the amplitude of vibration and the amplification factors on drag and lift coefficients, but also shifts the natural frequencies at which the maximum amplitude and maximum amplification occur to larger values.