Vortex-Induced Vibration (VIV) is a concern when dealing with slender, flexible structural members of deepwater platforms. While much is known about the characteristics of VIV in uniform and sheared current flows, very little is known about it in combined wave-induced cyclic and uniform current flows. The cyclic flows induced in this experimental study are a result of either regular or random waves. The uniform current is obtained by towing the model. In addition to understanding the mechanisms that generate VIV in various environments, the suppression of VIV is also an important concern. This study utilizes a large size horizontal cylinder model and the Offshore Technology Research Center wave basin to generate data on VIV in current-only, wave-only, and combined wave and current environments. Mud is known about various forms of VIV suppression, but there has been limited study on the optimum use of such coverage. Two types of VIV suppression devices, airfoil and ribbon type fairings, were investigated for coverages varying from 100% to 40% to determine their effectiveness. With the data obtained, present thinking on VIV prediction method in uniform currents was verified and new insight into the effects of controlled wave conditions on VIV was obtained. Both spectral and statistical characterizations of the experimental measurements were made and areas for further study identified.
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