Numerical analysis of configuration for steel lazy-wave riser in deepwater

The steel lazy-wave riser (SLWR) is modelled by nonlinear large-deformation beam theory. The equilibrium equations of the SLWR are established based on Minimum Total Potential Energy Principle. The numerical solution adopts an incremental iterative method, which can effectively deal with the riser-seabed interaction and avoid the complexity of contact detection. The method can be used for parameter optimisation. Firstly, introduced the overall configuration and characteristics of SLWR. Secondly, discuss the different working conditions of SLWR. Lastly, it describes how to choose a reasonable range of parameter research and determine each optimal configuration option. The method was verified with Orcaflex. Through static analysis, the effects of water depth, horizontal span, upper catenary length, extreme sea conditions, and motion of vessel on the configuration of the riser, top tension, bending moment, and shear force distribution are obtained.