EVALUATING RISER INTERFERENCE FROM EXPERIMENTAL AND NUMERICAL ANALYSIS

摘要

When the oil exploration and exploitation moved away from the shore to deeper ocean, the riser interference became an important issue to be addressed during platform design. It became so important, particularly, when a great numbers of rigid risers are installed on the platform. Those kinds of risers are particularly used at Spar buoy and TLP platform.A conservative approach for riser interference design can result on the oversize platform or to reduce the number of wells hanging on it. On the other hand, a non conservative approach can bring serious problems, like collision of risers, which can cause a dent on the riser wall and it may reduce its fatigue life.In order to identify the hydrodynamic behavior of one riser placed in the vicinity of other one, Petrobras R&D Center carried out some experimental and numerical studies for getting their hydrodynamic behavior when they are aligned and spaced by 2, 3, and 5 times diameter.