The server is under maintenance between 08:00 to 12:00 (GMT+08:00), and please visit later.
We apologize for any inconvenience caused
Login  | Sign Up  |  Oriprobe Inc. Feed
China/Asia On Demand
Journal Articles
Bookmark and Share
Study on the Vortex-Induced Vibration Characteristics for Drilling Risers Evacuated from Typhoon in the Hard Hang-Off Mode
Pages: 94-100
Year: Issue:  2
Journal: Ocean Technology

Keyword:  drilling risershard hang-off modevortex induced vibration (VIV)buoyancy modulesevacuation from typhoon;
Abstract: For safety considerations, drilling platform is needed to be evacuated with the risers hung off in advance of encountering severe typhoons during drilling operations. There exists a security risk due to vortex-induced vibration (VIV) under the interaction of ocean currents and the navigation of the platform. In this paper, the SHEAR7 software is used to study the VIV characteristics of the drilling risers of the HYSY981, a deepwater semi-submersible drilling platform, under the hard hang-off mode when evacuating platform with risers under the current speed in once-in-a-year environmental conditions in the South China Sea. The study shows that the tension of risers lowers with higher coverage rate of buoyancy modules. Moreover, the distribution of buoyancy modules has considerable impact on VIV response which is weakest in the alternative arrangement scheme of 25% coverage. However, shorter risers are not necessarily better, it is needed to analyze the combined effects of ocean currents, configuration of risers and the navigation conditions of the platform. The computing results indicate that it is necessary to avoid the layout of buoyancy modules in high current velocity areas as well as avoid sailing the platform upstream.
Related Articles
No related articles found