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 of reducing the load of a rotor blade of a wind turbine during installation of the wind turbine, whereby the rotor blade includes an aerodynamic device such as a vortex generator or a noise reducer is provided. The method includes the steps of attaching a cover on the rotor blade for covering at least a part of the aerodynamic device before lifting the rotor blade to the top of the tower of the wind turbine, and detaching the cover subsequently. An arrangement including a rotor blade of a wind turbine and such a cover, is also provided.

An improved wind turbine blade assembly for a wind turbine, and an improved wind turbine, having multiple airfoils, specifically, at least a primary airfoil and a secondary airfoil with an aerodynamic gap therebetween.

Method of operating a wind turbine comprising a plurality of blades rotatable along their longitudinal axes using a pitch mechanism, and comprising one or more movable trailing edge surfaces. The method includes predicting, at a first moment in time, a high load for one or more of the blades at a second moment in time. The method further comprises actuating on one or more of the movable trailing edge surfaces of these blades such that the trailing edge surfaces have a wider range of control to counteract the predicted high loads before the second moment in time, and simultaneously pitching the blades such as not to negatively affect the operation of the wind turbine. The method furthermore comprises, at the second moment in time, actuating the one or more movable trailing edge surfaces of the at least one or more blades to counteract the high loads.

Provided is a wind turbine and to a method and a device for controlling aerodynamic properties of a blade of the wind turbine, the blade including a predetermined number of add-on members which are actuated by a corresponding trim actuator to alter the aerodynamic properties of the blade, wherein each trim actuator is configured to hold the add-on member in a predetermined first position and a predetermined second position. The control device is configured to determine a first number of add-on members which are to be held at the predetermined first position, and to determine a second number of add-on members which are to be held at the predetermined second position.

A method for damping vibration in a wind turbine including aerodynamic devices for influencing the airflow flowing from the leading edge of a rotor blade of the wind turbine to the trailing edge of the rotor blade, each aerodynamic device being movable by an actuator between a first protruded configuration and a second retracted configuration is provided. The method includes measuring vibrations in the wind turbine, if the measured vibrations are greater than a threshold within a predefined frequency band, moving a portion of the aerodynamic devices to the second retracted configuration and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, reducing the pitch angle interval of the blade and continuing to measure vibrations, if the measured vibrations are still greater than a threshold within a frequency band, moving all the aerodynamic devices to the second retracted configuration.

A rotor blade of a wind turbine, wherein the rotor blade) includes a suction side, a pressure side, a trailing edge section with a trailing edge, and a leading edge section with a leading edge is provided. The rotor blade furthermore includes an air duct at the trailing edge section which provides a flow path from the pressure side to the suction side. The air duct includes an inlet portion) and an outlet portion, and the air duct is configured such that at least a portion of the airflow from the leading edge section to the trailing edge section is permanently guided through the air duct.

The invention regards an apparatus or method for controlling the profile of a blade on a wind turbine having at least a first blade and a second blade, the first blade comprise at least one first sensor system adapted to determine a first blade state and the second blade comprise at least one second sensor system adapted to determine a second blade state, wherein the profile of the second blade is controlled based on the determined first blade state and the determined second blade state.

Wind turbine blade comprising at least one deformable trailing edge section having a plurality of actuators consecutively arranged substantially downstream from one another and a control system for controlling the actuators, wherein a downstream end of one actuator is connected by a substantially rigid link with an upstream end of the next actuator and the plurality of actuators comprises an upper actuator being mounted above a chord line of the blade section and a lower actuator being mounted below a chord line of the blade section. Wind turbines comprising such a blade and methods of controlling loads on a wind turbine blade are also described.

Provided is an arrangement for controlling inflow and outflow of a fluid into and out of an expandable container arranged to change a state of an adaptable flow regulating device installed at a wind turbine rotor blade, the arrangement including: an inflow valve arranged to control fluid inflow into the container; an outflow valve arranged to control fluid outflow out of the container; wherein the inflow valve and the outflow valve are configured to prohibit fluid flow into and/or out of the container in case of safety stop event.