Abstract:
A rotary wing aircraft including a vehicle vibration control system. The vehicle vibration control system includes a rotary wing aircraft member sensor for outputting rotary wing aircraft member data correlating to the relative rotation of the rotating rotary wing hub member rotating relative to the nonrotating body, at least a first nonrotating body vibration sensor, the at least first nonrotating body vibration sensor outputting at least first nonrotating body vibration sensor data correlating to vibrations, at least a first nonrotating body circular force generator, the at least a first nonrotating body circular force generator fixedly coupled with the nonrotating body, the at least first nonrotating body circular force generator controlled to produce a rotating force with a controllable rotating force magnitude and a controllable rotating force phase, the controllable rotating force magnitude controlled from a minimal force magnitude up to a maximum force magnitude, and with the controllable rotating force phase controlled in reference to the rotary wing aircraft member sensor data correlating to the relative rotation of the rotating rotary wing hub rotating relative to the nonrotating body wherein the vibration sensed by the at least first nonrotating body vibration sensor is reduced.
Abstract:
A turbine blade system including a first turbine blade and a second turbine blade being arranged adjacent to each other shall be suited to allow a particularly secure and reliable operation of a turbine. To this end, the turbine blades are in contact in a first surface area and separated from each other in a second surface area, wherein the first turbine blade includes a pocket containing a damping piece in the second surface area.
Abstract:
A turbine wheel including: a plurality of first and second blades, at least one of the first blades being adjacent to at least one of the second blades; a disk presenting an axis of rotation and a periphery having the blades mounted thereat, each of the blades including a head solid with a root engaged in a housing that opens to the periphery of the disk, each of the blades including a keying mechanism including a respective shelf arranged between the head and the root of the blade, the shelves of the first blades presenting an azimuth length different from the azimuth length of the shelves of the second blades; and a damper device arranged at least between the adjacent blades, the damper device being arranged between the shelves of the blades and the periphery of the disk.
Abstract:
The present invention provides a structural element, in particular for an aircraft and spacecraft, comprising a core, the rigidity of which varies at least in portions for optimising the aeroelastic characteristics of the structural element The present invention also provides a method for producing a structural element, in particular for an aircraft and spacecraft, which comprises the following steps: provision of a structural element comprising a core; determination of the aeroelastic behavior of the structural element; and variation, at least in portions, of the rigidity of the core of the structural element such that the aeroelastic behavior of the structural element is optimised. The present invention further provides an aircraft and spacecraft comprising a structural element of this type, and a rotor blade, in particular for a wind turbine, comprising a structural element of this type.
Abstract:
A damper pin for coupling platforms of adjacent turbine blades includes a first flat longitudinal end region, a second flat longitudinal end region and a reduced cross sectional area. The reduced cross sectional area is separated from the first flat longitudinal end region by a first main body region and the reduced cross sectional area is separated from the second flat longitudinal end region by a second main body region. The cross sectional area of the reduced cross sectional area is less than the cross sectional area of each of the first and second main body regions.
Abstract:
Vibration damping is important with regard to such components as hollow turbine blades in gas turbine engines. Traditionally damping has occurred through damping elements secured at the root or tip of such blades. Such damping is not optimised and results in potential problems with wear in operational life. By providing a tube of deformable material which can be located within a hollow cavity it is possible to provide an element which through friction engagement can absorb vibration energy and therefore damp such vibration. The tube incorporates a number of cuts and/or grooves in an appropriate pattern in order to define a deformation profile once the tube is expanded in location. The tube is secured in position internally upon an expandable element which is typically an inflatable device. Once in position the tube is retained in its expanded deformable profile and the engagement between the tube and the hollow cavity wall surface results in energy absorption through vibration episodes. It is also possible to provide a tube formed from a shape memory alloy which will expand of its own right in location to engage the hollow cavity wall surfaces for energy absorption during vibration episodes.
Abstract:
An airfoil component and method for producing the component. The component has root and airfoil portions, the latter having an airfoil tip and oppositely-disposed concave and convex surfaces that converge at leading and trailing edges of the airfoil portion. The airfoil portion has at least one stiffener between first and second walls thereof that define the concave and convex surfaces, respectively. The stiffener defines multiple internal cavities within the airfoil portion that extend in the span-wise direction of the airfoil portion. A polymeric material fills at least one of the internal cavities and is bonded to the airfoil portion only at an extremity of the internal cavity nearer the root portion, and not to the stiffener or to the first and second walls of the airfoil portion, to define an internal damping member that provides a vibratory damping effect to the airfoil portion.
Abstract:
A helicopter having a rotor, a fuselage, and a transmission connected functionally to the rotor; the helicopter has a supporting body supporting at least the transmission, and connecting means having a first connecting member and at least one second connecting member connected to the supporting body and the fuselage respectively; and the connecting means have elastic means interposed between the first and second connecting member.
Abstract:
The present invention provides a structural element, in particular for an aircraft and spacecraft, comprising a core, the rigidity of which varies at least in portions for optimising the aeroelastic characteristics of the structural element The present invention also provides a method for producing a structural element, in particular for an aircraft and spacecraft, which comprises the following steps: provision of a structural element comprising a core; determination of the aeroelastic behaviour of the structural element; and variation, at least in portions, of the rigidity of the core of the structural element such that the aeroelastic behaviour of the structural element is optimised. The present invention further provides an aircraft and spacecraft comprising a structural element of this type, and a rotor blade, in particular for a wind turbine, comprising a structural element of this type.
Abstract:
The present invention relates to an improvement to rotorcraft rotors (1) fitted with inter-blade drag dampers (15) such that for each blade (4), the two joints (16) connecting said blade (4) to two inter-blade drag dampers (15) are disposed on either side of the pitch variation axis (101) of said blade, at least one of the two joints (16) being offset to above the plane P containing the pitch variation axis (101) and the vertical flapping axis (102).