An Investigation on the Dynamic Compression of Steel Lazy-Wave Risers

The steel lazy-wave riser is a good alternative for deepwater oil and gas exploitation, as its buoyancy section alleviates the top tension and TDP (touchdown point) movements. Some studies exist on dynamic compression instability in SCR (steel catenary risers), but no studies have been found on dynamic compression in SLWR (steel lazy-wave risers). This article focuses on investigating the occurrence of dynamic compression in the upper segment of steel lazy-wave risers to assess if the analytical formulation for catenary risers available in the literature is applicable. The methodology for catenary risers is implemented, verified, and then applied to a steel lazy-wave riser case study. The results show that the model developed for catenary risers did not get accurate results for the lazy-wave configuration but was always on the safe side.