Compared with those offshore oil development platforms using wet wellhead, dry wellhead has advantages of drilling, production and maintenance management. At present, the TLP and SPAR platforms which use dry wellhead have poor liquid storage capacity. On the other hand, the vertical motion of FPSO platform with strong storage capacity is too extreme to meet the requirements of dry wellhead system. In present work, a floating column with dry-well and storage platform (FCDS platform) is proposed based on the FWPSO platform. After adding an extension cylinder and the new damping structure to the bottom of the platform, the hydrodynamic performance is investigated by the numerical algorithm. Taking the sea scenarios in the South China Sea into account, a time-domain coupling analysis was adopted to simulate the dynamic performance of the buoy-mooring system. The maximum horizontal displacement and the maximum tension of the mooring line are compared and analyzed. The results show the FCDS platform with "chain-polyester-chain" type mooring system can meet the motion response requirements and the mooring system can also meet the requirements of the specification.
The crude, which is one of the major energy resources, has played an important role in the society development. As the onshore oil storage becomes less and less, more attentions are paid on the offshore areas. According to previous surveys (Yacovitch et al., 2020; Kaiser, 2020), the offshore oil has reached about 30% of the whole production in 2019, and it will be undoubtedly increasing and become the major contributor in the following years.
For the offshore oil and gas development, the facilities and equipment are located on the offshore platforms. According to the water depth of their working area and connection type to the seafloor, there are two main kinds of offshore oil and gas platforms. One kind is the fixed platform, such as jacket, gravity-based platform, etc. They are directly supported by the piles or other structures which are injected stably in the seabed. Due to the continuous structure to the seafloor and its construction cost, the fixed platform is usually adopted in the shallow water areas. On the other hand, when the offshore oil development steps into the deep water areas, the fixed platforms are seldom adopted because of the establish cost and safety factors. Therefore, the floating structures positioned by anchor and mooring lines become the most common choice.
