초심해역에서 오일/가스 개발을 위한 SLWR의 설계 및 해석

Abstract

The riser is one of the most important system for deepwater oil field development, which can transfer production fluid such as gas, oil and water from well to topside of processing platform on sea surface. There are several types of riser systems, depending on the material, configuration, and layout. Among these possible selections, Steel Lazy Wave Riser(SLWR) is recently increasing for the development of oil and gas in the ultra deepwater, because it can reduce excessive line tension at the hang-off position and fatigue damage at the touchdown point. A lazy wave configuration can be implemented using buoyancy modules attached in the middle of the SLWR, which gives rise to strong nonlinear problem. In this paper, design on SLWR in the water depth of 1,600m is presented and its safety in the static and dynamic point of view is investigated. Due to SLWR with strong geometric non-linearity, it needs the robust and stable method to find the static configuration. The dynamic relaxation method is known to be more stable and more robust than conventional methods with large deflection. Therefore, the dynamic relaxation method is developed and applied to estimate the static configuration of the SLWR. The dynamic response of the SLWR using finite element method is estimated from static configuration using dynamic relaxation method. Meanwhile, the configuration of the SLWR varies depending on the density and flow pattern of the