Vortex-induced vibration current tank tests of two equal-diameter cylinders in tandem

Tests have been performed on equal diameter ABS cylinders in tandem subjected to uniform and sheared flows in a current tank at subcritical Reynolds numbers. An accelerometer on each cylinder was used to measure the vortex-induced vibration response, which primarily varied between the third and seventh transverse bending modes. The results reveal some interesting relationships between the responses of the two cylinders when plotted against the upstream cylinder displacements. In addition, it was discovered that the downstream cylinder consistently experiences bimodal response even when the upstream cylinder response is dominated by a single mode.