A rotor blade, with a suction side and a pressure side, for a wind turbine, having a rotor blade root of a hub region for attaching the rotor blade to a rotor hub, a rotor blade tip, which is arranged on a side, facing away from the rotor blade root, of a tip region, at least one vortex generator, which is arranged between the rotor blade root and the rotor blade tip, wherein the at least one vortex generator comprises swirl elements with a length and a height, which are arranged one next to the other in a longitudinal direction of the rotor blade and are in each case oriented at an angle to a main flow direction of the rotor blade, wherein, in the longitudinal direction of the rotor blade, the swirl elements have a lateral spacing to one another. A variation in the geometry of the swirl elements is realized in a manner dependent on a respective distance between the arrangement of the swirl elements and the rotor blade root.

Disclosed are methods and apparatuses for mitigating the formation of concentrated wake vortex structures generated from lifting or thrust-generating bodies and maneuvering control surfaces wherein the use of contour surface geometries promotes vortex-mixing of high and low flow fluids. The methods and apparatuses can be combined with various drag reduction techniques, such as the use of riblets of various types and/or compliant surfaces (passive and active). Such combinations form unique structures for various fluid dynamic control applications to suppress transiently growing forms of boundary layer disturbances in a manner that significantly improves performance and has improved control dynamics.

A wind power generation system has a windmill, a lift improvement device, a power generator, a storage, and a controller. The windmill rotates when receiving an airflow. The lift improvement device has a capability of operating and halting, the lift improvement device increases a lift force to a blade of the windmill when operating. The power generator generates power by rotation of the windmill and a torque is generated in a direction suppressing rotation of the windmill. The storage stores a plurality of characteristic maps indicating characteristics of the torques of the power generator in relation to rotation speeds of the power generator. The controller controls a power generation amount of the power generator by switching and using the plurality of characteristic maps of the storage in correspondence with a state of operating or halting of the lift improvement device.

A lift modifying device for a rotor blade of a wind turbine is provided, the lifting modifying device including at least one fluid jet module and at least one compressed fluid source, wherein the at least one fluid jet module includes multiple fluid jets, which are fluidically connected to the at least one compressed fluid source, the at least one fluid jet module is configured to be arranged at a suction side or a pressure side of an airfoil of the rotor blade, and the at least one fluid jet module is configured to generate a fluid curtain separating an air flow on the suction side the pressure side of the airfoil, when the rotor blade is provided with the lift modifying device on its suction side or pressure side and the at least one compressed fluid source supplies compressed fluid to the at least one fluid jet module.

A method for iteratively estimating a wind speed at a wind turbine is disclosed, said wind turbine comprising a rotor carrying a set of wind turbine blades, each wind turbine blade having a variable pitch angle. A minimum tip speed ratio, λ.sub.min, is derived, based on an obtained pitch angle, θ. The minimum tip speed ratio, λ.sub.min, defines a limit between a stable and an unstable control region. An initial tip speed ratio, λ.sub.init>λ.sub.min, is selected, and an initial estimated wind speed, v.sub.init, is derived based on the initial tip speed ratio, λ.sub.int, and an obtained rotational speed, ω, of the rotor. An estimated wind speed, v.sub.est, is iteratively derived, based on the obtained rotational speed, ω, and the obtained pitch angle, ω, and using the derived initial estimated wind speed, v.sub.init, as a starting point. The iterative process converges fast and reliably.

Disclosed are methods and apparatuses for mitigating the formation of concentrated wake vortex structures generated from lifting or thrust-generating bodies and maneuvering control surfaces wherein the use of contour surface geometries promotes vortex-mixing of high and low flow fluids. The methods and apparatuses can be combined with various drag reduction techniques, such as the use of riblets of various types and/or compliant surfaces (passive and active). Such combinations form unique structures for various fluid dynamic control applications to suppress transiently growing forms of boundary layer disturbances in a manner that significantly improves performance and has improved control dynamics.

Wind turbine blade comprising a shape modifiable airfoil section that extends both chordwise and spanwise and has a not modified default shape, a conduit that extends from the inside of the blade towards the outside of the blade, and an outer part comprising a flow regulator that is located at the shape modifiable airfoil section and blocks the conduit when the shape modifiable airfoil section presents its default shape, and does not block the conduit when the shape modifiable airfoil section presents a modified shape. In the latter situation the conduit is opened to the outside of the blade and a device for exchanging a fluid between the inside and the outside of the blade is thus defined.

A wind turbine rotor blade (1) with a blunt, wide and/or cut off trailing edge (15) in a hub region (111), with an air-conducting channel (23) extending radially outward for conducting suctioned air from a suction region (21) to a blow-out region (22) arranged in the blade tip region (113) inside the wind turbine rotor blade (1), wherein and boundary layer suctioning occurs on the top side (13) of the wind turbine rotor blade (1), and a boundary layer fence (28) is provided in the hub region (111) near the hub fastening means (17) in order to prevent a flow in the direction of the hub fastening means (17).

Consistent kinetic energy is harvested from wind and from flowing water in streams, rivers and tidal flows using a translating large sail, foil or wing which is permitted to translate in one direction, followed by translating in the opposite direction while pushing or pulling a cable, rod, or tether which in turn turns a pulley, wheel or other device from which traditional sources of power can be generated. The pulley wheel can be used to generate electricity, create hydrogen from water by electrolysis, compress air for transmission or storage, charge batteries, or perform work such as pumping water, heating water, moving objects, etc.

A method for optimizing multiple airfoil wind turbine blades, having, specifically, at least a primary airfoil and a secondary airfoil with an aerodynamic gap therebetween. an optimized multiple airfoil wind turbine blade assembly, and a modular method for manufacturing and assembling the same.