Offshore towing.

Towing Analysis

Delmar Systems’ towing analysis is a fully coupled time domain analysis which can be used to verify that the selected tow vessels are adequate for the operation and identify weather limitations with set bollard pull and line tension criteria.  We use state-of-the-art marine software packages are used for the analysis. ANSYS® AQWA™ is used to generate six degrees-of-freedom response amplitude operators (RAOs) and wave drift force (WDF) coefficients for all vessels involved. Orcina OrcaFlex™ is used for the global modeling and time domain tow simulation for the metocean cases and directions of interest.

Through this, we are able to determine:

  • Fully coupled multi-body time domain dynamic analysis
  • Independent six degrees-of-freedom hydrodynamic vessel panel models
  • Full equipment configuration / tow line properties modeled
  • Site-specific directional metocean

Our tow analysis objectives include determining if tow vessel(s) can maintain a forward rig speed and control of rig, maximum tow line tensions, and bollard pull recommendations for specific weather scenarios.  

Results include:

  • Tow line tension statistics
  • Tow speed statistics
  • Tow vessel bollard pull recommendations
  • Rig course made good (CMG) deviations
  • Tow vessel heading deviations
  • Travel distances over time