Wind Turbine Blade Drainage

Abstract

A wind turbine includes a tower supporting a drive train with a rotor, at least one hollow blade extending radially from the rotor; a drain hole arranged in a tip portion of the blade; a baffle, arranged inside the blade and inboard of the drain hole, for impeding a flow of particulate matter to the drain hole; a flexible drain conduit arranged inside the blade for connecting to the drain hole; and a non-flexible drain conduit arranged inside the blade for connecting to the flexible drain conduit, the non-flexible conduit having a plurality of openings for receiving fluid from inside the blade.

1 . A hollow blade for a wind turbine comprising a flexible drain conduit arranged inside the blade for connecting to a drain hole through a surface of the blade. 
   
   
       2 . The blade recited in  claim 1 , wherein the flexible drain conduit includes a plurality of openings for receiving fluid from inside the blade. 
   
   
       3 . The blade recited in  claim 2 , wherein an internal dimension of each of the openings is smaller than an internal dimension of the conduit. 
   
   
       4 . The blade recited in  claim 3 , wherein the conduit is tubular. 
   
   
       5 . The blade recited in  claim 3 , wherein a shape of the openings is selected from the group consisting of round, quadrilateral, square, slotted, and octagonal. 
   
   
       6 . The blade recited in  claim 3 , wherein the conduit is secured to an internal surface of the blade. 
   
   
       7 . The blade recited in  claim 6  wherein the flexible conduit is laminated to an internal surface of the blade. 
   
   
       8 . The blade recited in  claim 6 , wherein the flexible conduit is adhesively bonded to an internal surface of the blade. 
   
   
       9 . The blade recited in  claim 1 , further comprising a non-flexible drain conduit arranged inside the blade for connecting to the flexible drain conduit, the non-flexible conduit having a plurality of openings for receiving fluid from inside the blade. 
   
   
       10 . The blade recited in  claim 9  wherein the non-flexible drain conduit is laminated to an internal surface of the blade. 
   
   
       11 . The blade recited in  claim 9  wherein the non-flexible conduit is adhered to an internal surface of the blade. 
   
   
       12 . The blade recited in  claim 9  wherein the non-flexible conduit is integrally-formed with an internal surface of the blade. 
   
   
       13 . A hollow blade for a wind turbine, comprising
 a drain hole through a surface of the blade; and   a baffle, arranged inside the blade and inboard of the drain hole, for impeding a flow of particulate matter to the drain hole.   
   
   
       14 . The wind turbine blade recited in  claim 13 , wherein the baffle comprises
 a first deflector extending from a leading edge of the blade; and   a second deflector extending from a trailing edge of the blade.   
   
   
       15 . The wind turbine blade recited in  claim 14 , wherein the baffle further comprises a third deflector spaced apart from the leading and trailing edges of the blade. 
   
   
       16 . The wind turbine blade recited in  claim 15 , wherein at least a portion of at least one of the deflectors curves toward a root of the blade. 
   
   
       17 . The wind turbine blade recited in  claim 13 , further comprising:
 a flexible drain conduit arranged inside the blade for connecting to the drain hole; and   a non-flexible drain conduit arranged inside the blade for connecting to the flexible drain conduit, the non-flexible conduit having a plurality of openings for receiving fluid from inside the blade.   
   
   
       18 . A wind turbine, comprising:
 a tower supporting a drive train with a rotor;   at least one hollow blade extending radially from the rotor;   a drain hole arranged in a tip portion of the blade; and   a baffle, arranged inside the blade and inboard of the drain hole, for impeding a flow of particulate matter to the drain hole.   
   
   
       19 . The wind turbine recited in  claim 18 , wherein the baffle comprises
 a first deflector extending from a leading edge of the blade;   a second deflector extending from a trailing edge of the blade; and   a third deflector spaced apart from the leading and trailing edges of the blade.   
   
   
       20 . The wind turbine recited in  claim 18 , further comprising
 a flexible drain conduit arranged inside the blade for connecting to the drain hole; and   a non-flexible drain conduit arranged inside the blade for connecting to the flexible drain conduit, the non-flexible conduit having a plurality of openings for receiving fluid from inside the blade.