Systems and methods for reducing drag and/or vortex induced vibration

Abstract

There is disclosed a system for reducing drag and/or vortex induced vibration of a structure, the system comprising a fairing defining a plurality of perforations, wherein the fairing is suitable for placement around the structure, the perforations defining a porosity of the fairing of at least 1%.

1 . A system for reducing drag and/or vortex induced vibration of a structure, the system comprising: 
 a fairing defining a plurality of perforations, wherein the fairing is suitable for placement around the structure, the perforations defining a porosity of the fairing of at least 1%.    
   
   
       2 . The system of  claim 1 , wherein the fairing comprises a porosity from 2% to 80%.  
   
   
       3 . The system of  claim 1 , wherein the fairing comprises a front and a tail, wherein the perforations comprise at least one centered perforation at the front, and at least one perforation at the tail.  
   
   
       4 . The system of  claim 1 , wherein the fairing comprises a front and a tail, wherein the perforations comprise at least two off-centered perforations at the front, and at least one perforation at the tail.  
   
   
       5 . The system of  claim 1 , wherein the fairing comprises a front and a tail, wherein the perforations provide a fluid path within the fairing from the front to the tail and around the structure, when the fairing is placed around the structure, and the structure is placed in a flowing-fluid.  
   
   
       6 . The system of  claim 1 , wherein at least one of the perforations comprise a shape selected from the group consisting of regular n-sided, irregular n-sided, linear, and curvilinear geometric shapes.  
   
   
       7 . The system of  claim 1 , wherein at least one of the perforations comprise a shape selected from the group consisting of square, rectangle, triangle, circle, oval, and ellipsoid.  
   
   
       8 . The system of  claim 1 , wherein the perforations are arranged in a regular pattern.  
   
   
       9 . The system of  claim 1 , wherein the fairing comprises a teardrop shape.  
   
   
       10 . A method for modifying a structure subject to drag and/or vortex induced vibration, said method comprising: 
 positioning at least one fairing around the structure, wherein the at least one fairing defines a plurality of perforations, the perforations defining a porosity of the fairing of at least 1%.    
   
   
       11 . The method of  claim 10 , wherein the positioning comprises positioning at least two fairings about the structure.  
   
   
       12 . The method of  claim 10 , further comprising: 
 positioning a collar, a buoyancy module, and a clamp around the structure.    
   
   
       13 . The method of  claim 10 , wherein the fairing comprises a teardrop shape.  
   
   
       14 . The method of  claim 10 , wherein the fairing comprises a porosity from 2% to 80%.