The Steel Catenary Riser (SCR) concept has many advantages compared with other riser concepts and has been widely used for decades in deep water oil and gas production. Once the SCR has been installed in deep water field, the replacement of SCR is almost impossible so SCR should have enough fatigue strength. Therefore, the prediction of fatigue life is very important for developing SCR. The Vortex Induced Vibration (VIV) is an important source of fatigue damage for SCR. For riser system, the fatigue damage due to VIV can be calculated with the use of S/W SHEAR 7. This program was developed for predicting the VIV response based on various theoretical models and experiments. Parameters for VIV response calculation in this program were also determined through various experiments and experiences. For better understanding of VIV response, it is necessary to investigate the effect of parameters which affects the analysis result. This paper summarizes the results of parametric study performed to enhance the understanding of relationship between each parameter and fatigue analysis result.
The Steel Catenary Riser (SCR) is simple and cost effective system among the riser systems. For many decades, SCR has been adopted for several offshore projects. Most rules and regulations for riser design, however, only specify the functional requirements and basic analysis method or initial scantlings. They do not suggest detailed analysis methods for riser fatigue analysis. Therefore, it is imperative that engineers select appropriate analysis procedure to get valid results. In general, for riser, the fatigue damage due to environments can be divided into two damages. They are from the wave action and vortex phenomenon.
In case of vortex phenomenon, there are two terms. They are Vortex Induced Vibration (VIV) acting on riser and the other one is Vortex Induced Motion (VIM) acting on floater. This paper focuses on VIV fatigue analysis.