The present disclosure provides a blade for a wind turbine, where the blade extends in a lengthwise direction between a root end and a tip end of the blade. The blade comprises a leeward shell portion and a windward shell portion, each of the shell portions defining respective inner and outer surfaces extending in a chordwise direction between a leading edge of the blade and a trailing edge of the blade. The blade further comprises a first windward reinforcement structure, a first leeward reinforcement structure, a second windward reinforcement structure, and a second leeward reinforcement structure, the reinforcement structures being arranged internally within the blade and extending in the lengthwise direction of the blade. The second windward and second leeward reinforcement structures are arranged closer to the trailing edge than the first windward reinforcement structure and the first leeward reinforcement structure, respectively, and the second windward reinforcement structure is longer than the second leeward reinforcement structure in the lengthwise direction.

Described herein is a rotor blade assembly (100) and a method for generating a lift in a fluid installation. The rotor blade assembly includes an arcuate rotor blade (102) that is configured to be rotated about its axis Y. One or more motion transmitting members (106, 114, 116) are provided that connect the arcuate rotor blade with at least one power generating member (104) for transmitting torque from the arcuate rotor blade to the at least one power generating member (104). The fluid incident on the arcuate rotor blade is caused to flow over a first leading edge L1 of a rotor blade towards a central rib R of the rotor blade (102). This fluid flow is then caused to flow along the central rib R of the rotor blade towards a stem section of the rotor blade from where the fluid exits, thereby causing rotation of the rotor blade.

A blade noise reduction device, comprising a plurality of sawtooth units. The plurality of sawtooth units are arranged in a first direction. Each sawtooth unit comprises secondary teeth and a primary tooth, which extend in a second direction, wherein at least one secondary tooth is distributed on each of two sides of the primary tooth, the tooth vertex angle of the secondary tooth being smaller than the tooth vertex angle of the primary tooth. The blade noise reduction device can remarkably improve the noise reduction effect. In addition, the present invention further relates to a blade having the blade noise reduction device, and a wind turbine generator set having the blade.

A spar cap is for a wind turbine rotor blade. The spar cap includes a stack of fiber material layers, which are stacked in a stacking direction from a bottom face to a top face, and a clipping layer which is arranged on the top face of the stack. The clipping layer protrudes beyond the stack of fiber material layers in a lateral direction which is perpendicular to the stacking direction. A set is for manufacturing a half shell of a wind turbine rotor blade. An assembly includes a spar cap and a mold. A method is for manufacturing a half shell of a wind turbine rotor blade.

The invention describes a wind turbine rotor blade active flap (1) comprising a primary body (1P) adapted for mounting to the trailing edge (20.sub.TE) of a wind turbine rotor blade (20); a flap turning means (10, 11, 12) adapted to turn the active flap (1) between a neutral position (R.sub.0), in which the active flap (1) directs airflow (A.sub.20S, A.sub.20P) towards the suction side (P.sub.20S) of the rotor blade (20), and a working position (R-R.sub.max), in which the active flap (1) directs airflow (A.sub.20S, A.sub.20P) towards the pressure side (P.sub.20P) of the rotor blade (20); and a secondary body (1S) mounted to the primary body (1P) and configured to hold the active flap (1) in its neutral position (R.sub.0). The invention further describes a wind turbine (2) comprising a number of rotor blades (20) mounted to a hub; and an active flap (1) according to the invention, mounted to the trailing edge (20.sub.TE) of each rotor blade (20).

A method of forming a rotor blade includes positioning first dry skin layer(s) in a first mold. The method also includes placing a wedge-shaped core material having a mounting surface atop the first dry skin(s) in the first mold at a trailing edge end of the rotor blade. The method further includes infusing the first dry skin layer(s) and the core material together via a resin material to form a first shell member. The method includes applying an adhesive onto the mounting surface and then placing a second mold with a second shell member arranged therein atop the first mold containing the first shell member to form the rotor blade such that a portion of the second shell member rests atop the mounting surface. Thus, the method includes securing the shell members together via the adhesive, wherein the core material supports the trailing edge end of the rotor blade.