Wind turbine blades comprising one or more deformable trailing edge sections having a multistable sheet comprising a plurality of bistable elements, each bistable element having two stable positions, wherein the multistable sheet is attached in a cantilever manner to a structural portion of the blade and extends in a chordwise direction, and the multistable sheet is connected to a skin of the blade such that upon changing one or more bistable elements from one stable position to the other stable position a shape of the trailing edge section changes. The application further relates to wind turbines comprising such blades and methods of controlling loads on the blades.

A turbofan engine has an engine case and a gaspath through the engine case. A fan has a circumferential array of fan blades. The engine further has a compressor, a combustor, a gas generating turbine, and a low pressure turbine section. A speed reduction mechanism couples the low pressure turbine section to the fan. A bypass area ratio is greater than about 6.0. The low pressure turbine section airfoil count to bypass area ratio is below about 170.

A turbofan engine according to an example of the present disclosure includes, among other things, an engine case and a gaspath through the engine case. A fan has a circumferential array of fan blades. The engine further has a compressor, a combustor, a gas generating turbine, and a low pressure turbine section. A speed reduction mechanism couples the low pressure turbine section to the fan. A bypass area ratio is greater than about 6.0. The low pressure turbine section airfoil count to bypass area ratio is below about 170.

In a first aspect, there is a method of making a rotor blade, including designing at least one of an upper skin, a lower skin, a support network, and components therefor; and forming at least one of the upper skin, the lower skin, a support network, and components therefor using an additive manufacturing process. In a second aspect, there is an airfoil member having a root end, a tip end, a leading edge, and a trailing edge, the airfoil member including an upper skin; a lower skin; and a support network having a plurality of interconnected support members in a lattice arrangement and/or a reticulated arrangement, the support network being configured to provide tailored characteristics of the airfoil member. Also provided are methods and systems for repairing an airfoil member.

A ram air turbine (RAT) is provided and includes a turbine assembly including blades and a hub to which the blades are connected, a generator or a pump and a drivetrain mechanically interposed between the turbine assembly and the generator or the pump. Each blade includes an exterior, airfoil-shaped structure defining an interior and support structures disposed within the interior which connect with an inner surface of the exterior, airfoil-shaped structure and which define hollow regions within the interior.

A turbofan engine according to an example of the present disclosure includes, among other things, a fan including a circumferential array of fan blades, a compressor in fluid communication with the fan, the compressor including a first compressor section and a second compressor, the second compressor section including a second compressor section inlet with a second compressor section inlet annulus area, a fan duct including a fan duct annulus area outboard of the second compressor section inlet, a shaft assembly having a first portion and a second portion, a turbine in fluid communication with the combustor, the turbine having a first turbine section coupled to the first portion of the shaft assembly to drive the first compressor section, and a second turbine section coupled to the second portion of the shaft assembly to drive the fan, an epicyclic transmission coupled to the fan and rotatable by the second turbine section through the second portion of the shaft assembly to allow the second turbine to turn faster than the fan, wherein the second turbine section includes a maximum gas path radius and the fan blades include a maximum radius, and a ratio of the maximum gas path radius to the maximum radius of the fan blades is less than 0.6.

A turbofan engine according to an example of the present disclosure includes, among other things, a fan including an array of fan blades rotatable about an engine axis, a compressor including a first compressor section and a second compressor section, the second compressor section including a second compressor section inlet with a compressor inlet annulus area, a fan duct including a fan duct annulus area outboard of the second compressor section inlet, and a turbine having a first turbine section driving the first compressor section, a second turbine section driving the fan through an epicyclic gearbox, the second turbine section including blades and vanes, and wherein the second turbine section defines a maximum gas path radius and the fan blades define a maximum radius, and a ratio of the maximum gas path radius to the maximum radius of the fan blades is less than 0.6.

A turbofan engine has an engine case and a gaspath through the engine case. A fan has a circumferential array of fan blades. The engine further has a compressor, a combustor, a gas generating turbine, and a low pressure turbine section. A speed reduction mechanism couples the low pressure turbine section to the fan. A bypass area ratio is greater than about 6.0. The low pressure turbine section airfoil count to bypass area ratio is below about 170.

A novel cost effective low profile structure that converts and stores solar radiation into heat and electricity for controlled utilization. The inventive material incorporates a large insulated vault or chamber of substantial thermal mass connected to a series of inlet passages and to a solar collector assembly. As solar radiation is collected by the solar collector assembly a temperature gradient is created between the collector and the air that is within the vault resulting in air being drawn out of the chamber and through the collector assembly. This air movement is utilized to rotate turbines that are coupled to the inlet passages generating electricity. The hot air is also captured and utilized. The system provides for an efficient, economical process of harnessing and utilizing solar energy by capitalizing on not only on its thermal nature, but its motive nature as well.

The invention relates to a concrete construction of modular design, comprising at least two upright precast concrete wall elements (7, 7, . . . , 7) which are arranged next to one another and, where appropriate, above one another and have two narrow sides, an upper and a lower side and a front and a rear side, wherein a first honeycomb support (1) is anchored in one of the narrow sides and the opposite narrow side has a recess or depression (8) in which a further honeycomb support (1) is anchored in such a way that, when mounting the narrow sides of the two precast concrete wall elements (7, 7), the two honeycomb supports (1, 1) can be connected by connecting means (9) with the formation of the vertical joint (16).