22nd June 2011

Transocean releases investigation report for Deepwater Horizon

Transocean has released its investigation report into the loss of the Deepwater Horizon.

The CFD investigation into the gas dispersion following the loss of control of the Macondo well, which is documented in Appendix P of the report, was led by Steve Howell of Abercus on behalf of Prospect Flow Solutions.

A number of Abercus' software technologies were employed during the course of the CFD studies:

  • GeomAuditry was used to handle the drawings received from Transocean and create a reference geometry database for use in the subsequent CFD gas dispersion analysis. GeomAuditry also provided the required functionality for dividing this reference geometry into primary geometry, which was taken forward to the unstructured CFD mesher, and the secondary geometry, which was compiled into a separate congestion database.
  • JET was used to organise the complex CFD model set-up. There were many separate internal areas that needed to be included within the CFD model, complete with a detailed capture of the interconnecting ventilation ductwork, and in some areas there were several revisions of geometry as more information became available during the course of the investigation. The deployment of JET managed this whole process effectively, allowing multiple users to simultaneously work on the CFD model in different areas of the rig.
    Sub-models were subsequently compiled into the complete model for the entire vessel, which was embedded within a larger external domain aligned with the wind direction of interest for the CFD simulations. This whole process was handled automatically by JET.
  • The ACE method was used to import the congestion database compiled by GeomAuditry and automatically allocate the associated congestion resistances throughout the CFD model (which included both unstructured and structured orthogonal meshes in different parts of the model).