Vortex induced vibration suppression systems and methods

Abstract

A system comprising a subsea structure defining an interior of the system, the structure subject to a water current; a sleeve exterior to the subsea structure, covering at least a portion of an outside surface of the subsea structure; and a vortex induced vibration suppression device exterior to the sleeve.

1 . A system, comprising:
 a subsea structure defining an interior of the system, the structure subject to a water current;   a sleeve exterior to the subsea structure, covering at least a portion of an outside surface of the subsea structure; and   a vortex induced vibration suppression device exterior to the sleeve.   
   
   
       2 . The system of  claim 1 , wherein the subsea structure is selected from an umbilical, a riser, and a tendon. 
   
   
       3 . The system of  claim 1 , wherein the sleeve comprises an exterior surface having a Young's modulus of at least 2 GPa. 
   
   
       4 . The system of  claim 1 , wherein the vortex induced vibration suppression device comprises a fairing or a helical strake. 
   
   
       5 . The system of  claim 1 , wherein the subsea structure comprises an exterior surface having a Young's modulus less than 2 GPa. 
   
   
       6 . The system of  claim 1 , wherein the sleeve is buoyant in water, the system further comprising a collar connected to the subsea structure above the sleeve, the collar adapted to retain the sleeve in an axial location along the subsea structure. 
   
   
       7 . The system of  claim 1 , wherein the sleeve is negatively buoyant in water, the system further comprising a collar connected to the subsea structure below the sleeve, the collar adapted to retain the sleeve in an axial location along the subsea structure. 
   
   
       8 . The system of  claim 1 , wherein the sleeve comprises one or more ledges extending exterior to the sleeve, for example circumferential ledges. 
   
   
       9 . The system of  claim 8 , wherein the vortex induced vibration suppression device comprises one or more shoulders adapted to interface with the one or more ledges. 
   
   
       10 . The system of  claim 1 , further comprising a plurality of sleeves. 
   
   
       11 . The system of  claim 10 , further comprising a plurality of vortex induced vibration suppression devices exterior to the plurality of sleeves. 
   
   
       12 . The system of  claim 11 , further comprising a collar between two adjacent vortex induced vibration suppression devices. 
   
   
       13 . A method, comprising:
 installing a subsea structure in a body of water, wherein the subsea structure is subject to one or more water currents;   installing at least one sleeve exterior to the subsea structure, covering at least a portion of an outside surface of the subsea structure; and   installing at least one vortex induced vibration suppression device exterior to the sleeve.   
   
   
       14 . The method of  claim 13 , further comprising:
 installing at least one collar exterior to the subsea structure, the collar adapted to retain the fairing and/or the sleeve in an axial location along the subsea structure.   
   
   
       15 . The method of  claim 13 , wherein the sleeve comprises an exterior surface having a Young's modulus of at least 2 GPa. 
   
   
       16 . The method of  claim 13 , wherein the subsea structure comprises an exterior surface having a Young's modulus less than 2 GPa. 
   
   
       17 . The method of  claim 13 , wherein the sleeve is installed on the subsea structure before the subsea structure is installed in the body of water. 
   
   
       18 . The method of  claim 13 , wherein the vortex induced vibration suppression device is installed on the subsea structure after the subsea structure is installed in the body of water.