Effects of tension on vortex-induced vibration (VIV) responses of a long tensioned cylinder in uniform flows
- 137 Downloads
The effects of tension on vortex-induced vibration (VIV) responses for a tension-dominated long cylinder with an aspect ratio of 550 in uniform flows are experimentally investigated in this paper. The results show that elevated tension suppresses fluctuations of maximum displacement with respect to flow velocity and makes chaotic VIV more likely to appear. With respect to periodic VIV, if elevated tension is applied, the dominant vibration frequency in the in-line (IL) direction will switch from a fundamental vibration frequency to twice the value of the fundamental vibration frequency, which results in a ratio of the dominant vibration frequency in the IL direction to that in the cross-flow direction of 2.0. The suppression of the elevated tension in the fluctuation of the maximum displacement causes the axial tension to become an active control parameter for the VIV maximum displacement of a tension-dominated long riser or tether of an engineering structure in deep oceans. However, the axial tension must be optimized before being used since the high dominant vibration frequency due to the elevated tension may unfavorably affect the fatigue life of the riser or tether.
KeywordsTension effect Maximum displacement Dominant vibration frequency Chaos
- 6.Wu, X.D., Ge, F., Hong, Y.S.: A review of recent studies on vortex-induced vibrations of long flexible cylinders. J. Fluid Struct. 28, 292–308 (2012)Google Scholar
- 7.Wu, X.D., Ge, F., Hong, Y.S.: An Experimental investigation of dual-resonant and non-resonant responses for vortex-induced vibration of a long slender cylinder. Sci. China Phys. Mech. 57, 321–329 (2014)Google Scholar
- 9.Resvanis, T.L., Jhingran, V., Vandiver, J.K., et al.: Reynolds number effects on the vortex-induced vibration of flexible marine risers. In: Proceedings of the ASME 2012 31st International Conference on Ocean, Offshore and Arctic Engineering, Brazil, OMAE2012-83565 (2012)Google Scholar
- 19.Rosenstein, M.T., Collins, J.J., De Luca, C.J.: A practical method for calculating largest Lyapunov exponents from small data. Phys. D 65, 117–134 (1993)Google Scholar