CFD approach to flow-induced vibrations of tandemly placed circular cylinders

In the present study, we numerically examined the vibration characteristics of two cylinders which were placed tandemly in close vicinity of each other. The center-to-center pitch between the cylinders was four times the diameter of the cylinders. The cylinders were modeled as rigid bodies with two degrees-of-freedom in the simulation. The vibration frequencies of the cylinders were calculated, with the reduced velocity being varied. The vortex formation process was observed with regard to reduced velocity and structural damping. Also, the effects of the reduced velocity of the flow, the eigenfrequency of the cylinder, and the structural damping of the cylinder on the vibration response were discussed. A comparison was made between numerical results and the experimental ones obtained by means of the high-speed particle image velocimetry (Dynamic PIV) measurement.