Acoustically Linked, Remotely Operated Vehicle Deployable, Subsea VIV Measurement System on XVIII: Development, Testing, Deployment and Results

摘要

In August 1998, a 10-inch Steel Catenary Riser (SCR) wasrninstalled on the Petrobras XVIII semi-submersible productionrnplatform, moored in 910 meters water depth in the Marlimrnfield, Campos Basin, offshore Brazil [1]. This was the firstrnSCR ever installed on a floating moored platform.rnIn order to evaluate and verify the methodologies and torncalibrate the numerical models used in the riser, mooringrnsystem and platform design, it was necessary to establish arnmonitoring program for all the relevant parametersrn(environmental, platform positions and motions, riser loadsrnand stresses at the top and at the touch down point (TDP) andrnvortex induced vibrations) [2].rnThe TDP monitoring system was described in Edwardsrn1999 [3]. In February 2000, the Vortex Induced VibrationrnMonitoring System (VIVMS) was added for measuring andrnrecording vibrations of the SCR induced by flow and by thernmotions of the semi-submersible platform P XVIII.rnThis paper describes the VIVMS, which was developed tornmeasure, at up to four locations along the SCR, accelerationsrnin three orthogonal directions and angular rates in tworndirections. The system records this information locally inrnsubsea enclosures, transmits it to the surface on command andrnincludes the software to transform the riser fixed accelerationsrnand rates to earth fixed linear and angular velocities andrndisplacements.