Hydrodynamics of a Blowout Preventer


Motivated by safe design of ultra-deep offshore wells, an investigation of the hydrodynamic performance of a riser-BOP´┐╝(Blowout Preventer) system has been conducted.

This initial study investigated the potential VIV characteristics of a new BOP design. Forced vibration experiments of a scaled model in a towing tank were used to build a database of hydrodynamic coefficients. These will then be incorporated into a detailed model of the global riser dynamics. CFD was used to reveal the underlying mechanisms.

Figure 1. 3D-printed, scaled model of the BOP.

Figure 2. Left: Sample hydrodynamic database (Cd ) for BOP. Right: CFD on the BOP oscillating in still water highlights a large vortex ring.

Global Riser-BOP-Casing Model

Figure 3. Riser with BOP undergoing wave-induced excitation.

A global model of the riser-BOP-casing system has been developed. It is implemented into code, which includes the riser secWon encountering wave excitation at a point along its length, a BOP section with distinct mass and bending properties and with externally imposed hydrodynamic coefficients, and a soil/casing region modeled with equivalent springs and dashpots.