Towed sensor array surface structure apparatus and method of use thereof

Abstract

A surface structure is provided for reducing drag and/or for reducing turbulence on or proximate any element of a streamer cable or towed sensor array. The surface structure comprises a non-uniform surface having ridges, channels, expanding channels, dimples, bumps, backward facing diamonds, a saw tooth pattern, or the like integrated into, adhered to, wrapped, and/or coated onto a surface of the streamer cable. The sharkskin like material, coating, or surface is optionally an array of denticles or a sheet that is also useful for fuel reduction and/or ease of guidance due to lower resistance and noise reduction in towed sensors due to reduction/breakup of localized zones of turbulence.

1 . An apparatus, comprising:
 a towed sensor array, said towed sensor array comprising:
 a leading end; 
 a trailing end, during use said leading end leading said trailing end along a towing axis; and 
 an outer surface, said outer surface comprising an array of surface elements, said surface elements comprising:
 a plurality of channels; and 
 a plurality of ridges. 
 
   
     
     
         2 . The apparatus of  claim 1 , at least ninety percent of said ridges predominantly aligned along the towing axis and at least ninety percent of said channels predominantly aligned along the towing axis. 
     
     
         3 . The apparatus of  claim 2 , said plurality of ridges comprising:
 a first width between two ridges of said plurality of ridges;   a second width between said two ridges, said second width greater than fifty percent larger than said first width, said first width directionally leading said second width along the towing axis during use.   
     
     
         4 . The apparatus of  claim 2 , wherein a majority of said plurality of ridges further comprise at least one of:
 a curved leading edge; and   a curved upper edge.   
     
     
         5 . The apparatus of  claim 2 , said plurality of channels comprising:
 a first maximum depth of a first channel of said plurality of channels;   a second maximum depth of a second channel of said plurality of channels, said first maximum depth at least fifty percent deeper than said second maximum depth.   
     
     
         6 . The apparatus of  claim 2 , wherein said array of surface elements comprises a non-uniform array of surface elements. 
     
     
         7 . The apparatus of  claim 2 , wherein a portion of said array of surface elements combine to form a saw tooth shaped trailing edge. 
     
     
         8 . The apparatus of  claim 2 , wherein said array of surface elements comprise a series of bumps, wherein said series of bumps extended outward by at least one millimeter. 
     
     
         9 . The apparatus of  claim 2 , said array of surface elements comprising a repeating pattern. 
     
     
         10 . The apparatus of  claim 2 , said array of surface elements comprising a random pattern. 
     
     
         11 . The apparatus of  claim 2 , wherein a first element of said array of surface elements partially overlaps a second element of said array of surface elements. 
     
     
         12 . The apparatus of  claim 2 , said towed sensor array further comprising:
 a hollow tube; and   an elastomeric flexible syntactic flotation material over-molded about said hollow tube, wherein said outer surface comprises a layer affixed to an outer surface of said elastomeric flexible syntactic flotation material.   
     
     
         13 . The apparatus of  claim 12 , further comprising:
 a gap in coverage of said elastomeric flexible syntactic flotation material by said array of surface elements of at least three percent of a surface area of said outer surface of said towed sensor array.   
     
     
         14 . The apparatus of  claim 12 , wherein an outer surface of said elastomeric flexible syntactic flotation material comprises said plurality of channels and said plurality of ridges. 
     
     
         15 . The apparatus of  claim 1 , said towed sensor array comprising any of:
 a cable section;   a sensor section;   a connector section; and   a positioner section, said positioner section configured to control at least depth of said sensor section,   wherein said outer surface comprises an outer surface of any of: said cable section, said sensor section, said connector section, and said positioner section.   
     
     
         16 . The apparatus of  claim 15 , wherein said sensor section of said towed sensor array comprises a piezoelectric sensing element, wherein said outer surface comprises a coating of said sensor section radially outward from said piezoelectric sensing element. 
     
     
         17 . The apparatus of  claim 1 , said array of surface elements comprising a non-uniform surface shark-skin simulant. 
     
     
         18 . The apparatus of  claim 1 , further comprising a biocide impregnated into said outer surface of said towed sensor array. 
     
     
         19 . A method, comprising the steps of:
 towing a towed sensor array through a water body along a towing axis, said towed sensor array comprising:
 a leading end; 
 a trailing end, said leading end and said trailing end defining the towing axis; and 
 an outer surface, said outer surface comprising an array of surface elements, said array of surface elements comprising:
 a plurality of channels; and 
 a plurality of ridges; and 
 
   reducing localized turbulence proximate said outer surface of said towed sensor array using said array of surface elements.   
     
     
         20 . The method of  claim 19 , further comprising the step of:
 generating a localized low pressure region proximate said outer surface of said towed array sensor using curved outer surfaces on said plurality of ridges by towing the towed sensor array through the body of water.   
     
     
         21 . The method of  claim 20 , further comprising the step of:
 breaking apart a localized turbulence using said generated localized low pressure region.   
     
     
         22 . The method of  claim 21 , further comprising the step of:
 providing an inward radial compression force on an element of said towed sensor array using a fabric, said fabric forming said outer surface of said towed sensor array.