This paper presents a comprehensive study on the hydrodynamic performance of a new dry tree semisubmersible concept, Deepwater Tumbler Platform (DTP). The DTP concept is developed to suit the environmental conditions of South China Sea (SCS) and to tackle the challenges in deepwater development of oil and gas resources in SCS. A life-time feasibility study has been conducted, and this paper mainly focuses on the hydrodynamics of such a concept. Both frequency domain analysis and nonlinear time-domain dynamic analysis have been conducted, which include:
hydrodynamic characteristics;
load response;
frequency domain analysis;
nonlinear timedomain dynamic analysis.
With the great development of China's economy and the improvement of people's living conditions, China's demand for oil and gas has been increasing during recent years. The South China Sea (SCS) is one of the four world-renowned offshore oil and gas resources. A preliminary estimate of the geological oil resources in the SCS's deep water totals 8.686 billion tons, with the expected recoverable resources at 2.733 billion tons; the geological natural gas resources are expected to total 5.96 trillion cubic m, with recoverable resources reaching 3.68 trillion cubic meters (Chen, 2009). However, the complexities of extreme environmental conditions, distribution of deepwater oilfields, and the status quo of China's deepwater equipment and infrastructures in SCS bring huge challenges for the development of deepwater resources. In such circumstances, when selecting a deepwater floating production platform used for deepwater oilfields in SCS, following characteristics should be in pursuit of. From the viewpoint of improving safety, platforms with better stability should be preferred. From the viewpoint of reducing offshore installation time and cost, it would be better that the topsides and hull can be integrated at quayside and towed to site in a whole piece.