Longitude was instructed by Siem Offshore Contractors GmbH (SOC) to carry out a cable installation analysis relating to the inter-array cables (CAF 1620 and CAF 1621) for the Veja Mate Offshore Project (VMOP) off the coast of the Germany, for their new custom designed cable lay vessel, Siem Aimery. A seakeeping analysis was also completed on their new support vessel Siem Moxie.

Dynamic analyses were run in Orcaflex investigating numerous combination of environmental conditions in order to assess the limiting sea-state for the operations.

Scope of work included:

  • Cable lay vessel shallow water RAOs generation
  • Monopile and OSS platform cable first end pulling
  • Cable lay
  • Monopile and OSS platform second end pulling
  • Wet Storage seabed stability

The analyses were refined in close consultation with the SOC operational personnel in order to fully capture how issues such as TDP compression and MBR are mitigated during actual onboard operations with refined vessel offsets and back tension. This direct modelling to reflect operations allowed for improved design seastate limits to minimise vessel downtime.

Longitude provided a responsive service to SOC including a re-run of the whole set of analyses in a short timescale due to last minute changes in the cables properties. This was possible thanks to the in-house tools developed by Longitude in Python for automating the selection of worst cases, the set-up and post-processing of the Orcaflex simulations.