A locking unit (24) for a rotor lock system (20) of a wind turbine (1), the locking unit (24) comprising: a locking shaft (34) that is slidably movable within a barrel (30) under the influence of an actuator (32); and an angular drive arrangement (48, 50) which is configured to enable angular movement of the locking shaft (34) about a longitudinal axis as the locking shaft (34) is moved linearly within the barrel (30) by the actuator (32).

Various embodiments of an airfoil and machines with airfoils are disclosed. The airfoils include a thicker leading airfoil portion and a thinner trailing airfoil portion. In one embodiment, the leading airfoil portion is formed by bending a body of the airfoil back toward itself. In another embodiment, the leading airfoil portion has a solid geometry and includes two elliptic surfaces. To prevent detachment of airflow, the leading airfoil portion includes at least two arc portions or surfaces that act to direct the airflow down to the trailing airfoil portion in a manner that stabilizes vortexes that may form in the region of changing thickness.

A ceiling fan or similar air-moving device can include a motor for rotating one or more blades to drive a volume of air about a space. The blade can include a body having an outer surface with a flat top surface and a flat bottom surface, and a side edge. A curved transition can extend between one of the flat top surface or the flat bottom surface, and the side edge. The curved transition can include an elliptical curvature.

Disclosed is a multiple blade wind turbine (MBWT). The MBWT includes: at least one rotor comprising two closed loop tracks positioned parallel or equidistant to one another and a plurality of airfoils interspaced within the tracks. The plurality of airfoils are connected at each end to one of said tracks and are fully rotatable with respect to said closed loop tracks. A transmission is connected to one of the tracks. The track drives the transmission and an electric generator is connected to said transmission for generating electricity. The rotors are oriented vertically or horizontally with respect to a vertical support structure that is used to support the rotors. The MBWT's design allows the electric generator(s) and transmission system to be housed relatively close to ground level. This configuration reduces the mass of the central support tower and reduces the construction and ongoing maintenance costs.

Disclosed is a wave energy power generation apparatus, comprising a plurality of wave energy collecting units. Each of the wave collecting units comprises: a potential energy collecting assembly used for collecting wave potential energy, a kinetic energy collecting assembly used for collecting wave kinetic energy and a positioning assembly used for vertically limiting and horizontally positioning buoyancy compartments. The apparatus is beneficial for improving the collection efficiency of wave energy, and simultaneously can satisfy the purposes of long-term safe and stable operation, of being adapted for scaled construction.

A ram air turbine rotor comprises at least one intra-flow path shroud structure coupled between rotor blades, along a radial position between a support disc and an outer rim. The shroud structure includes shroud sectors each coupled between a respective pair of blades. The sectors each include a first edge adjacent to leading edges of the respective pair of blades, the first edge including a first curved segment, and a second edge adjacent to trailing edges of the respective pair of blades, the second edge including a second curved segment. The curved segments are each partially defined by a respective ellipse having a semi-major axis and a semi-minor axis. The semi-major axis is a portion of a spanwise distance between the respective pair of blades. The semi-minor axis is a portion of an axial distance between the leading edge of one blade and the trailing edge of an adjacent blade.

A gas turbine engine comprising a set of circumferentially adjacent airfoils, the airfoils having an outer wall defining a pressure side and a suction side extending between a leading edge and a trailing edge to define a stream-wise direction, and between a root and a tip to define a span-wise direction, and a set of dimples provide on the outer wall of at least one of the airfoils, the set of dimples spaced in at least one of the stream-wise or span-wise directions.

A locking unit (24) for a rotor lock system (20) of a wind turbine (1), the locking unit (24) comprising: a locking shaft (34) that is slidably movable within a barrel (30) under the influence of an actuator (32); and an angular drive arrangement (48, 50) which is configured to enable angular movement of the locking shaft (34) about a longitudinal axis as the locking shaft (34) is moved linearly within the barrel (30) by the actuator (32).

Provided is a trailing edge assembly of a wind turbine rotor blade, which includes a mounting portion; a flap portion flexibly connected to the mounting portion so that a flap angle subtended between the mounting portion and the flap portion can be altered; a volume adjustable chamber arranged between the mounting portion and the flap portion and realised to alter its volume between a minimum volume associated with a minimum flap angle and a maximum volume associated with a maximum flap angle; and at least one tube to face into an airflow passing over the airfoil region of the rotor blade, and an inner orifice arranged to face into the interior of the volume adjustable chamber such that an airflow between the outer orifice and the inner orifice alters the volume of the volume adjustable chamber. Embodiments of the invention further describe a wind turbine rotor blade.

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.