Numerical Simulations of Dynamic Pipeline-Vessel Response on a Deepwater S-Laying Vessel

The dynamic action induced on offshore pipelines by deepwater S-laying is significant, and directly determines how the pipeline structures are designed and installed. Existing research has not fully investigated the benefits of coupling models of pipeline and pipelaying vessel motions. Therefore, this paper presents a coupled time-domain numerical model for examining the effect of coupled dynamic reactions. The coupled model takes into account the motion of the pipelaying vessel, surface waves, ocean currents, wind forces, pipeline dynamics, and contact between the rollers and the pipeline. A proportional, integral, derivative (PID) controller was used for simulating the control of the pipelaying vessel. The hydrodynamic forces that the pipeline experiences were modeled using the Morison equation. The model was solved using Newmark’s method and verified using OrcaFlex software. The model was then used to analyze practical operations: the laying of a 22″ gas export pipeline on the seabed by the pipelaying vessel HYSY201 in the Pingbei-Huangyan gas fields in the East China Sea. The effects of coupled factors on pipelaying vessel motions and pipeline dynamics were approximated. These effects included configurations, axial tensions, and bending moments. The results show a significant connection between the dynamic responses of the pipelines and pipelaying vessel motions.