Investigation into Optimised Design of Flexible Riser Systems

P.A.Brown, A.Soltanahmadi, R.Chandwani, I.Larsen

The Institute of Marine Engineers, London, Oct. 1989

During the last seven years, Zentech Consultants have been involved in a number of projects that may be broadly classified within the heading 'Analysis and Design of Flexible Riser Systems'. The basis for their involvement has been the development of an advanced analytical tool for detailed design and hydrodynamic response of these systems. This paper summarises some of the experience gained by Zentech over the last seven year and presents an investigation into optimisation techniques used during design of single and multiple flexible riser systems. An introduction to this subject is given which addresses the reasons behind performing advanced analysis within the design procedure. The purpose and definition of flexible riser systems and the characteristics of flexible pipe are also presented, followed by a discussion of the methodology commonly used within design. The analytical tools required during design are identified and guidelines are given for validation of these software packages. A series of case studies showing typical system analysis are then presented with emphasis on parameters used for system optimisation.