Provided is a composite material for a wind turbine blade, the composite material including a plurality of rigid elements and plurality of flexible elements, wherein each flexible element is arranged between two rigid elements and is connected thereto such that the rigid elements are flexibly connected to each other by the flexible elements. The flexibility of the composite material can be achieved by using the interspaces between the rigid elements. Therefore, when the composite material is placed on a curved surface, hollow spaces between the rigid elements may be reduced or avoided.

Wind turbine blade having a length L, an airfoil with a chord C, and a first Gurney flap attached to the pressure or the suction surface of the airfoil near the trailing edge of the wind turbine blade. The first Gurney flap extends along at least 50% of the length of the outer ⅓rd of the wind turbine blade. By mounting the Gurney flap to the outer portion of the blade, the lift of the outer portion of the blade can be increased or decreased depending on the conditions in which the wind turbine is operating.

A rotor blade for a wind energy installation includes a blade root, a blade tip, and at least one rotor blade shell extending in a longitudinal direction from the blade root to the blade tip, and having an inner shell region and an outer shell region. The inner shell region includes a first fiber composite with at least two first fiber layers, and the outer shell region includes a second fiber composite with at least two second fiber layers. The first and second fiber layers extend substantially in the longitudinal direction. At least a first fiber layer of the first fiber composite terminates in the region of at least one end position in the longitudinal direction, whereas the remaining first fiber layers extend beyond the end position. At least a second fiber layer of the second fiber composite terminates in the region of the end position in the longitudinal direction, whereas the remaining second fiber layers extend beyond the end position.

A pultruded fibrous composite strip, a spar cap made from such strips, a wind turbine rotor blade having such a spar cap and a method for making a spar cap from such strips are provided. The strip is stacked with similar strips to form the spar cap. The strip has a substantially constant cross-section defined by first and second mutually opposed and longitudinally extending sides, and by first and second longitudinal edges. The first and the second sides include first and second abutment surfaces, respectively. The first and/or the second abutment surfaces has corrugated profile such that a plurality of longitudinally extending grooves are defined on the abutment surface having the corrugated profile. When the strip is stacked with similar strips, and subsequently resin is infused, the grooves on the abutment surface having the corrugated profile facilitate transfer and flow of the resin into spaces between the stacked strips.

A windmill blade includes a blade main body and a leading edge protector. The leading edge protector includes a conductive plate covering a leading edge, and a conductive mesh member connected to the conductive plate along a blade chord direction of the windmill blade. The conductive mesh member is provided with a plurality of holes. A skin or an adhesive at least partially enters the plurality of holes, so that the leading edge protector is fixed to the skin.

A windmill blade includes a leading edge protector provided at a leading edge portion of a blade main body including a skin surrounding a hollow space. The leading edge protector is fixed to the skin from the inner side of the hollow space.

A vortex generator defines a longitudinal direction and has two fins, which are each arranged at an angle in relation to the longitudinal direction and extend over a first length in the longitudinal direction, and a base, which connects the two fins to each other, the base having a width and extending over a second length in the longitudinal direction, wherein the second length is less than the first length over the entire width of the base.

There is described a rotor for a vertical axis wind turbine comprising: first and second blades connected to one another and arranged to rotate around an axis; wherein the first and second blades are disposed 180° apart with respect to one another and are offset from the axis in a radial direction; wherein an inner edge of each blade is spaced radially inwardly from an outer edge of the opposing blade to form a pair of diametrically opposed openings which open in opposite directions; wherein each of the first and second blades comprises a first curved section and a second oppositely curved section, the first and second curved sections being separated by a point of inflection; and wherein the first and second curved sections of the first and second blades overlap one another to form a passageway between the first and second blades which extends between the openings.

There is provided a wind turbine rotor blade having a blade outer side, a wall with a laminate, a blade inner side and at least a first and a second rotor blade part. The at least one first and second rotor blade parts are fixed together by means of at least one connecting unit in a separation plane. The connecting unit has at least one cable with a first end with cable fibers which are fixed in or at the laminate of the wall. The connecting unit has at least one projection at the first and second rotor blade parts respectively. The projections are respectively fixedly connected to the wall of rotor blade. The at least one cable is connected at at least one projection. The connecting unit has at least one tensioning element, by means of which the projections on the first and second rotor blade parts can be braced with each other.

A fluid and wind turbine system suitable for horizontal or vertical axis applications comprising (i) blades radially spaced around a rotational axis attached to a shaft by mounting formations so that the length axis of the mounting formations are substantially parallel to the width axis of the blades which mounting formations suspend the blades from the rotational axis creating a passageway allowing the air flow to pass through the turbine and impart a unidirectional rotational force to the shaft at all times the blades are exposed to the air flow on both the windward and leeward sides of the rotational axis (ii) an air flow director which shields the rotating blades from the air flow for a portion of their 360-degree rotation.