Pipe integrity and pipelay controller optimisation

In offshore pipelay, the combination of a real-time model of the vessel and pipe with an optimisation strategy is desired to maximise workability and minimise energy consumption during the laying process. Additionally, this strategy must ensure that the pipe’s structural integrity is not exceeded. From a literature review, it is concluded that an existing corotational FEM approach is the most suited to assess the structural integrity of the pipe and, where possible, give input for optimisation. This formulation has been further expanded, and the contact definition has been enhanced to allow continuous payout and pipe pulls. An adaptive feedforward algorithm has been developed to handle changing circumstances to optimise workability and minimise energy consumption during pipelay. The model has been statically and dynamically compared with the industry standard OrcaFlex and shows good agreement. The adaptive algorithm concept has been demonstrated, but more validation tests based on past project data are recommended.