Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) comprises a proximal support (310) configured to be arranged around a first portion (221) of a wind turbine blade (22), a distal support (320) configured to be arranged around a second portion (222) of the wind turbine blade (22), and a barrier (330) extending between the proximal support (310) and the distal support (320). The first portion (221) of the wind turbine blade (22) is at a different longitudinal position along the blade (22) than the second portion (222).

Abstract: The present disclosure relates to devices (300) for wind turbine blades (22) and methods for reducing vibrations in wind turbines (10). More particularly, the present disclosure relates to devices (300) for mitigating vortex induced vibrations and stall induced vibrations, wind turbine blades (22) comprising such devices (300), and methods for reducing wind turbine vibrations when the wind turbine (10) is parked, especially during wind turbine installation and/or maintenance. A device (300) comprises a proximal support (310) configured to be arranged around a first portion (221) of a wind turbine blade (22), a distal support (320) configured to be arranged around a second portion (222) of the wind turbine blade (22), and a barrier (330) extending between the proximal support (310) and the distal support (320). The first portion (221) of the wind turbine blade (22) is at a different longitudinal position along the blade (22) than the second portion (222).

Abstract: A particular arrangement of vortex generators for an airfoil is described. The vortex generators are provided in pairs, preferably on a wind turbine blade, wherein by arranging the vortex generators according to specified characteristics, a surprising improvement in blade performance is provided over the prior art systems.

Abstract: A transparent article made of glass ceramic with high surface quality as well as a method producing are provided. The article is suitable for use as a viewing pane. The method includes the steps of: producing a melt with a raw material composition that is suitable for a ceramization; hot shaping a flat substrate made of ceramizable green glass having two oppositely arranged, essentially flat surfaces from the melt; processing of at least one of the surfaces of the substrate with a smoothing fine-treatment process; ceramizing the substrate to produce the article made of glass ceramic.

Abstract: Disclosed is a wind turbine blade and a method for retrofitting a wind turbine blade, the wind turbine blade extending in a longitudinal direction along a pitch axis and having a tip end and a root end as well as a blade length, the wind turbine blade further comprising a profiled contour including a pressure side and a suction side, as well as a leading edge and a trailing edge with a chord having a chord length extending there between, the profiled contour, when being impacted by an incident airflow generating a lift, wherein the suction side of the wind turbine blade is provided with a plurality of vortex generators positioned along a mounting line having a proximal end point nearest the root end and a distal end point nearest the tip end, wherein the mounting line is a concave line seen from the trailing edge of the wind turbine blade.

Abstract: A particular arrangement of vortex generators for an airfoil is described. The vortex generators are provided in pairs, preferably on a wind turbine blade, wherein by arranging the vortex generators according to specified characteristics, a surprising improvement in blade performance is provided over the prior art systems.

Abstract: Disclosed is a wind turbine blade and a method for retrofitting a wind turbine blade, the wind turbine blade extending in a longitudinal direction along a pitch axis and having a tip end and a root end as well as a blade length, the wind turbine blade further comprising a profiled contour including a pressure side and a suction side, as well as a leading edge and a trailing edge with a chord having a chord length extending there between, the profiled contour, when being impacted by an incident airflow generating a lift, wherein the suction side of the wind turbine blade is provided with a plurality of vortex generators positioned along a mounting line having a proximal end point nearest the root end and a distal end point nearest the tip end, wherein the mounting line is a concave line seen from the trailing edge of the wind turbine blade.

Abstract: A method of automatically performing a patch test for a sonar system is disclosed, where data from a plurality of overlapping 3D sonar scans of a surface as the platform is moved are used to compensate for biases in mounting the sonar system on the platform.

Abstract: Data recorded by directing a single sonar beam pulse towards a surface, and recording the reflected sonar signals with a large plurality of detectors, is used to generate a mathematical representation of the surface. The mathematical representation of the surface is chosen to fit the recorded data according to a criterion such as a least squares fit of a plane to the recorded data points. A mathematical representation of on object is built up from a number of non-overlapping mathematical objects such as triangles, each triangle joined to adjoining triangles to form a continuous surface in three dimensions. Images of such mathematical representations are then presented to the observer.

Abstract: A wind shear detection and alert system, compensated for the calibrated airspeed of the aircraft to minimize nuisance wind shear alerts. The wind shear detection and alert system (10) determines a reference airspeed as a function of flap position, with respect to a minimum maneuver airspeed signal (60) provided by a stall warning computer on the aircraft. The reference airspeed is subtracted from a calibrated airspeed signal (76) that has been filtered to remove minor variations in the signal using a Laplace filter (68). The differential airspeed is further filtered by another Laplace filter (78), producing a filtered differential airspeed signal (70), which the system uses to determine a delta threshold (48) to be applied in compensation for the aircraft airspeed to a wind shear alert reference signal. As the filtered differential airspeed increases, the delta threshold signal increases the absolute level of the wind shear alert threshold, reducing the likelihood of unnecessary wind shear alerts.

Abstract: A process for the manufacture of 1,3,5-triaminotrinitrobenzene having a large crystal size by aminating 1,3,5-trichlorotrinitrobenzene with an agent at atmospheric pressure at a temperature of at least about 160.degree. C. with an antioxidant added to the reaction mixture.

Abstract: An improved inner loop control is disclosed for use in an aircraft pitch axis control system. Signals representative of vertical acceleration and pitch rate are complementary filtered and summed to produce an "inner loop" damping signal which is combined with "outer loop" command signals to produce an elevator control signal. The improved approach provides higher outer loop control law gains and better system stability, resulting in higher control bandwidth and tighter command tracking, especially in turbulence.

Abstract: Upon aircraft landing approach, flare path command signals of altitude, vertical velocity and vertical acceleration are generated as functions of aircraft position and velocity with respect to the ground. The command signals are compared with corresponding actual values to generate error signals which are used to control the flight path.

Abstract: Aircraft altitude, ground velocity, and altitude rate signals are input to a computer which, using a unique control law, generates a pitch control surface command signal suitable for guiding an aircraft on its flare path to a specified runway touchdown point despite varying wind conditions.