The focus of this research is on the developmentudand testing of a large-scale model riser (130 m in length)udundergoing high mode vortex induced vibrations (VIV) in theudocean environment. This large scale model will provide anudintermediate step between the common riser models (8-10 mudin length) that have mainly been used to research VIV to dateudand the actual 3,000+ m deepwater risers being used in industryudtoday.udDuring offshore drilling operations, marine risers carry mududand debris from below the sea floor, and during productionudoperations they are responsible for transporting oil or gas fromudthe hydrocarbon reservoir to the surface platform. The integrityudof a marine riser is therefore critical to the success of offshoreuddrilling and production.udThe flow of seawater around marine risers is subject to vortexudshedding which excites oscillations known as Vortex InducedudVibrations (VIV). When the VIV frequency approaches one ofudthe natural frequencies of the structure, resonance, or lock-inudoccurs. This results in enhancement of the vibration amplitude ofudthe structure and may have potentially destructive consequencesuddue to high bending stresses and fatigue damage of the riser. Atudpresent, the prediction of this phenomenon is one of the mostudchallenging areas in the offshore industry.udIn experimental investigations of VIV, large aspect ratio risers,udnamely long cylinders with relatively small diameters, pose audmodeling challenge. This paper focuses on the development of audlarge-scale model riser capable of transmitting data in real-timeudunder realistic operating conditions.
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