A method and system are provided for cooling a heat-exchanger in a wind turbine that has an electric generator with a cooling air flow directed therethrough. Effluent cooling air flow from the electric generator is directed into an air ejector pump and acts as motive air through the air ejector pump. Cold air is drawn into the air ejector pump by the vacuum generated by the motive air moving through the air ejector pump. The heat exchanger is disposed in-line with the cold air flow so that the cold air is drawn through the heat-exchanger, removes heat from the fluid circulated through the heat-exchanger, and becomes heated air that is combined with the motive air and discharged from the nacelle.

Wind turbine blades and wind turbine systems that include a co-flow jet are described. An example wind turbine blade has a main body and a fluid pressurizer. The main body has a first portion, a second portion, a leading edge, a trailing edge, an injection opening, a suction opening, and a channel. The first portion has a first cross-sectional shape and the second portion has a second cross-sectional shape that is different than the first cross-sectional shape. The injection opening is disposed on the first portion between the leading edge and the trailing edge. The channel extends from the suction opening to the injection opening. The fluid pressurizer is disposed within the channel.

An apparatus for generating energy through fluid dynamics includes a fluid reservoir, an energy extractor for extracting flow energy, a back-pressure control channel for circulating the fluid, and a pressure ejector for returning fluid to the fluid reservoir. The back-pressure control channel includes a fan-like device to generate a low-pressure region and draws fluid through the energy extractor. The energy extractor includes an energy extraction rotor to convert flow energy to rotation energy and may include a nozzle to alter flow characteristics of the fluid. The apparatus for generating energy may also include a settlement chamber to reduce flow disturbances.

A method and system are provided for cooling a heat-exchanger in a wind turbine that has an electric generator with a cooling air flow directed therethrough. Effluent cooling air flow from the electric generator is directed into an air ejector pump and acts as motive air through the air ejector pump. Cold air is drawn into the air ejector pump by the vacuum generated by the motive air moving through the air ejector pump. The heat exchanger is disposed in-line with the cold air flow so that the cold air is drawn through the heat-exchanger, removes heat from the fluid circulated through the heat-exchanger, and becomes heated air that is combined with the motive air and discharged from the nacelle.

According to an aspect, an ejector member includes an annular member; a vent arranged at the annular member, the vent having an inlet at a first surface of the annular member, the vent further having an outlet arranged radially inward from a second surface of the annular member; and a vane extending radially inward from the second surface of the annular member.

According to an aspect, an ejector member includes an annular member; a vent arranged at the annular member, the vent having an inlet at a first surface of the annular member, the vent further having an outlet arranged radially inward from a second surface of the annular member; and a vane extending radially inward from the second surface of the annular member.

An ejector assembly includes a primary nozzle in fluid communication with a primary fluid inlet, a secondary nozzle in fluid communication with a secondary fluid inlet, the primary nozzle being oriented concentrically within the secondary nozzle and the secondary nozzle having a venturi downstream of the primary nozzle, and the primary nozzle having a variable cross-sectional area. A gas turbine engine includes a source of high pressure air, a region of low pressure air, and an ejector assembly, the ejector assembly includes a primary nozzle in fluid communication with a primary fluid inlet, the primary fluid inlet in fluid communication with the source of high pressure air, a secondary nozzle in fluid communication with a secondary fluid inlet, the secondary fluid inlet in fluid communication with the region of low pressure air, the primary nozzle being oriented concentrically within the secondary nozzle and the secondary nozzle having a venturi downstream of the primary nozzle, and the primary nozzle having a variable cross-sectional area.

Disclosed is a compact vacuum pump including a housing having an internal vacuum chamber, an ejector pump axially mounted in the vacuum chamber, and an air filter coaxially mounted on the ejector pump. The housing has two separate compressed air supply lines one of which is a vacuum creation line extending to the inlet port of the ejector pump via a first supply line and the other of which is a vacuum release line extending to a gap between the ejector pump and the air filter via a second supply line. The vacuum pump is of a coaxial arrangement type and has a vacuum release function and a filter cleaning function.

An ejector assembly includes a primary nozzle in fluid communication with a primary fluid inlet, a secondary nozzle in fluid communication with a secondary fluid inlet, the primary nozzle being oriented concentrically within the secondary nozzle and the secondary nozzle having a venturi downstream of the primary nozzle, and the primary nozzle having a variable cross-sectional area. A gas turbine engine includes a source of high pressure air, a region of low pressure air, and an ejector assembly, the ejector assembly includes a primary nozzle in fluid communication with a primary fluid inlet, the primary fluid inlet in fluid communication with the source of high pressure air, a secondary nozzle in fluid communication with a secondary fluid inlet, the secondary fluid inlet in fluid communication with the region of low pressure air, the primary nozzle being oriented concentrically within the secondary nozzle and the secondary nozzle having a venturi downstream of the primary nozzle, and the primary nozzle having a variable cross-sectional area.

The blades of conventional wind turbines almost always have adjustable pitch; that is, they can be pivoted about their length in order to change the angle of attack of the blades to the wind. This is necessary, because the effective angle of attack varies with both wind speed and rotational speed. In particular, in extremely high wind speeds, the blades can be ‘feathered’ to reduce the amount of torque being imparted to the turbine. The present invention provides a wind turbine in which pressurised air may be conveyed to air outlets 21 on the blades 1. In this way, the aerodynamic behaviour of the blade 1 may be controlled, effectively feathering the blade without needing a robust mechanical system for pivoting the blade.