Abstract

Multiple Column Platform (MCP) semi-submersible is a newly proposed concept, which differs from the conventional semi-submersibles, featuring centre column and middle pontoon. It is paramount to ensure its structural reliability and safe operation at sea, and a rigorous investigation is conducted to examine the hydrodynamic and structural performance for the novel structure concept. In this paper, the numerical and experimental studies on the hydrodynamic performance of MCP are performed. Numerical simulations are conducted in both the frequency and time domains based on 3D potential theory. The numerical models are validated by experimental measurements obtained from extensive sets of model tests under both regular wave and irregular wave conditions. Moreover, a comparative study on MCP and two conventional semi-submersibles are carried out using numerical simulation. Specifically, the hydrodynamic characteristics, including hydrodynamic coefficients, natural periods and motion response amplitude operators (RAOs), mooring line tension are fully examined. The present study proves the feasibility of the novel MCP and demonstrates the potential possibility of optimization in the future study.

Highlights

  • Semi-submersible has been successfully applied in offshore industry since 1960s for oil and gas resources exploitation, accommodation, power supply, because of its excellent response performance, large payload capacity and convenient relocate-ability after field abandonment (Elosta et al, 2014)

  • Truss Pontoon Semi-submersible (TPS) is another innovative floating concept that inherits the advantages of a conventional semi-submersible and utilizes the added mass and the separated flow damping introduced by heave plates at the bottom of the truss columns, much like the Truss-Spar (Srinivasan et al, 2005)

  • The hydrodynamic performance of a newly proposed novel semi-submersible concept, the Multiple Column Platform (MCP) has been studied with a comprehensive numerical simulation complemented by scaled model test carried out in offshore basin

Read more

Summary

Introduction

Semi-submersible has been successfully applied in offshore industry since 1960s for oil and gas resources exploitation, accommodation, power supply, because of its excellent response performance, large payload capacity and convenient relocate-ability after field abandonment (Elosta et al, 2014). Jiang et al (2016) compared the motion and mooring loads statistics obtained from model test and coupled analysis to verify the reliability of numerical calculation and demonstrated the advantages of DTP novel semi-submersible design. This novel design of MCP, proposed by China Ship Development and Design Center, has a unique centre column and a supporting pontoon to achieve its function These structures can serve as the ballast tanks provides significant displacement for the hull to reduce the heave response, increase the platform stability, topside decks capacity, and the reactor thermal efficiency due to the external cold water. In subsection 6, a comparative study on the present novel design and two conventional semi-submersibles was performed in frequency domain. The potential effects on mooring loads due to wave drift and current drag resulted from the centre column and middle pontoon are discussed

Description of the MCP system
Features of mooring system
Experimental setups
Numerical model
Free decay tests
Comparative study
Findings
Conclusion
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call