Vortex induced vibration mitigation method and system

Abstract

Systems and methods for suppression of vortex induced vibration (VIV) in subsea conduits are disclosed, as may be used in oil and gas, carbon capture and storage, subsea mining or any other subsea operations where multiple conduits extend between a floating vessel and the sea floor and are subjected to VIV causing currents. VIV suppression elements may be wrapped around one or multiple conduits, and along their entire length or in regions where VIV effects are anticipated. The suppression members may also help to alleviate damage due to clashing of the conduits under the influence of the water currents.

1 . A system comprising:
 one or a plurality of fluid conduits extending from a vessel located above a well location and extending from the vessel through open water to the subsea well location;   vortex induced vibration (VIV) reducing members, a VIV reducing member being wrapped around each of the fluid conduits;   a control and communication umbilical extending from the vessel to the subsea well location; and   a wireline extendable and retractable from the vessel to the subsea well location independently of the fluid conduits and the control and communication umbilical.   
     
     
         2 . The system of  claim 1 , wherein the VIV reducing members are wrapped in the same direction on the fluid conduits. 
     
     
         3 . The system of  claim 1 , wherein the VIV reducing members are wrapped in opposite directions on the fluid conduits. 
     
     
         4 . The system of  claim 1 , wherein the control and communication umbilical is disposed adjacent to a first of the fluid conduits and is wrapped together with the first fluid conduit by a common VIV reducing member. 
     
     
         5 . The system of  claim 1 , wherein at least a first of the fluid conduits is wrapped by two VIV reducing members, the two VIV reducing members being wrapped in opposite directions on the first fluid conduit. 
     
     
         6 . The system of  claim 1 , wherein a plurality of control and communication umbilicals or a plurality of fluid conduits are wrapped together by a common VIV reducing member. 
     
     
         7 . The system of  claim 1 , wherein at least one of the VIV reducing members comprises a fluid or electrical control or communication conduit. 
     
     
         8 . A system comprising:
 a fluid conduit extending from a vessel located above a well location and extending from the vessel through open water to the subsea well location;   a vortex induced vibration (VIV) reducing member wrapped around the fluid conduit;   a control and communication umbilical extending from the vessel to the subsea well location independently of the fluid conduit; and   a wireline extendable and retractable from the vessel to the subsea well location independently of the fluid conduits and the control and communication umbilical.   
     
     
         9 . The system of  claim 8 , wherein the VIV reducing member comprises a fluid or electrical control or communication conduit. 
     
     
         10 . The system of  claim 8 , wherein the control and communication umbilical is also wrapped by a separate VIV reducing member separately from the fluid conduit. 
     
     
         11 . The system of  claim 8 , wherein the VIV reducing member is wrapped in a generally helical configuration with a pitch of between approximately 6 inches and 4 feet. 
     
     
         12 . The system of  claim 8 , wherein the VIV reducing member comprises a substantially round cross-section having a nominal diameter of between approximately ⅜ inch and 1.5 inches. 
     
     
         13 . The system of  claim 8 , wherein the VIV reducing member comprises a substantially flat tape-like material. 
     
     
         14 . The system of  claim 13 , wherein the VIV reducing member comprises a reinforcing element within or adjacent to the tape-like material. 
     
     
         15 . The system of  claim 8 , wherein the fluid conduit is wrapped by two VIV reducing members, the two VIV reducing members being wrapped in opposite directions along the fluid conduit in similar or intentionally different pitches. 
     
     
         16 . The system of  claim 15 , wherein the two VIV reducing members are wrapped in generally helical configurations having substantially the same pitch or differing pitches to create intentional overlap. 
     
     
         17 . The system of  claim 8 , wherein a ratio of a diameter of the VIV reducing member to a diameter of the fluid conduit is between approximately 1:4 and 1.15. 
     
     
         18 . A method comprising:
 separately wrapping a plurality of fluid conduits, one of which may be a rigid riser, with respective vortex induced vibration (VIV) reducing members, the fluid conduits, when deployed extending from a vessel located above a well location and extending from the vessel through open water to the subsea well location;   extending a control and communication umbilical from the vessel to the subsea well location independently of the fluid conduits; and   extending a wireline extendable and retractable from the vessel to the subsea well location independently of the fluid conduits and the control and communication umbilical.   
     
     
         19 . The method of  claim 18 , wherein the control and communication umbilical is also wrapped by a VIV reducing member separately from the fluid conduits. 
     
     
         20 . The method of  claim 18 , wherein at least one of the VIV reducing members comprises a fluid or electrical control or communication conduit.