FPSO 다점계류시스템 배치 방법에 따른 응답 특성 연구

초록

The performance of an offshore plant is closely related to the operation concept of the riser and offloading systems. Station-keeping is also important to maintain continuous and stable operation. This study is focused on the initial design of mooring system arrangement. As a first step, the hull responses such as motion RAOs and QTFs are calculated through frequency domain motion analysis. The obtained hull responses are used for the input data of frequency and time domain mooring analyses. Two types of spread mooring arrangements of 4x4 lines and 4x3 lines, which are to be applied a FPSO with 2.0 million barrel storage, are taken into account. In this paper, each consequence class of compared two types is separately assumed. Extensive comparison study demonstrates the 4x4 system is more stable in view of tension responses of moored lines. On the other side 4x3 system has better station-keeping capability under the restricted excursion range. It is concluded that comprehensive consideration of severity of environmental loads, possible excursion ranges, and costs for purchase and installation should be necessary for initial design of mooring arrangements.