Rotor blade for wind turbine

Abstract

A rotor blade for a wind turbine and a method for reducing rotor blade noise are disclosed. The rotor blade includes a body having exterior surfaces defining a pressure side, a suction side, a leading edge, and a trailing edge extending between a tip and a root, the surfaces further defining an interior. The rotor blade further includes at least one purge conduit defined in the tip and configured for exhausting air from the interior such that the air generally reduces noise at the tip.

1 . A rotor blade for a wind turbine, comprising:
 a body having exterior surfaces defining a pressure side, a suction side, a leading edge, and a trailing edge extending between a tip and a root, the surfaces further defining an interior; and,   at least one purge conduit defined in the tip and configured for exhausting air from the interior such that the air generally reduces noise at the tip.   
     
     
         2 . The rotor blade of  claim 1 , wherein the purge conduit tapers between an inlet and an outlet. 
     
     
         3 . The rotor blade of  claim 1 , wherein the purge conduit extends at an angle from perpendicular to the tip in the range between approximately 0° and approximately 80°. 
     
     
         4 . The rotor blade of  claim 1 , wherein the purge conduit is generally adjacent to the pressure side. 
     
     
         5 . The rotor blade of  claim 1 , wherein the purge conduit is generally adjacent to the suction side. 
     
     
         6 . The rotor blade of  claim 1 , further comprising a plurality of purge conduits. 
     
     
         7 . The rotor blade of  claim 1 , wherein the purge conduit is a slot. 
     
     
         8 . The rotor blade of  claim 1 , wherein the purge conduit is a hole. 
     
     
         9 . The rotor blade of  claim 1 , wherein the tip defines a local chord, and wherein the purge conduit is located between approximately 0% and approximately 80% of the local chord from the trailing edge. 
     
     
         10 . The rotor blade of  claim 1 , further comprising a stagnation zone defined on an exterior surface of the body, the stagnation zone defining at least one intake conduit configured to flow air to the interior of the body. 
     
     
         11 . The rotor blade of  claim 10 , wherein the body defines a span, and wherein the at least one intake conduit is located between approximately 0% and approximately 5% of the span from the tip. 
     
     
         12 . A wind turbine, comprising:
 at least one rotor blade, the at least one rotor blade comprising:
 a body having exterior surfaces defining a pressure side, a suction side, a leading edge, and a trailing edge extending between a tip and a root, the surfaces further defining an interior; and, 
 at least one purge conduit defined in the tip and configured for exhausting air from the interior such that the air generally reduces noise at the tip. 
   
     
     
         13 . The wind turbine of  claim 12 , wherein the purge conduit tapers between an inlet and an outlet. 
     
     
         14 . The wind turbine of  claim 12 , wherein the purge conduit extends at an angle from perpendicular to the tip in the range between approximately 0° and approximately 80°. 
     
     
         15 . The wind turbine of  claim 12 , further comprising a plurality of purge conduits. 
     
     
         16 . The wind turbine of  claim 12 , wherein the tip defines a local chord, and wherein the purge conduit is located between approximately 0% and approximately 80% of the local chord from the trailing edge. 
     
     
         17 . The wind turbine of  claim 12 , further comprising a stagnation zone defined on an exterior surface of the body, the stagnation zone defining at least one intake conduit configured to flow air to the interior of the body. 
     
     
         18 . The wind turbine of  claim 17 , wherein the body defines a span, and wherein the at least one intake conduit is located between approximately 0% and approximately 5% of the span from the tip. 
     
     
         19 . A method for reducing rotor blade noise, the method comprising:
 flowing air through an interior of the rotor blade, the rotor blade comprising a body having exterior surfaces defining a pressure side, a suction side, a leading edge, and a trailing edge extending between a tip and a root, the surfaces further defining the interior;   flowing at least a portion of the air through at least one purge conduit defined proximate the tip of the rotor blade; and   exhausting at least a portion of the air from the purge conduit such that the air interferes with a tip flow vortex and generally reduces noise at the tip.   
     
     
         20 . The method of  claim 19 , further comprising flowing air into the interior through at least one intake conduit, the intake conduit defined in a stagnation zone, the stagnation zone defined on an exterior surface of the body.