Abstract: The present disclosure relates to accelerometers. Various embodiments of the teachings thereof may be used in a generator. For example, a fiber-optic accelerometer may include: an optical fiber having a free end which vibrates under the influence of acceleration; a light source emitting light into the optical fiber at an opposite end of the fiber; a mirror arranged to reflect a portion of the light back into the optical fiber; and a detection device receiving reflected light at the opposite end of the fiber. The optical fiber may comprise a double-cladding fiber including a core, an internal cladding, and an external cladding.

Abstract: A temperature sensor arrangement for gas turbines is provided. The temperature sensor arrangement has a measuring probe. The measuring probe has a bore in which a steel tube is guided so as to be axially movable. The steel tube includes a glass fibre having Bragg grating measurement points for measuring the temperature. Elongate measurement openings enable hot gas to flow through the measuring probe, flowing round the steel tube in the region of the Bragg grating.

Abstract: A device for generating exhaust gas including a exhaust gas channel and a system. The system includes: a plurality of Bragg gratings distributed in positions transversely to the direction of flow of an exhaust gas at the end of the exhaust gas channel; an optical wave guide structure includes at least one optical wave guide and the Bragg gratings; and a heating device arranged adjacently to the Bragg gratings and through which the Bragg gratings are subjected to heat, or a cooling device arranged adjacently to the Bragg gratings, through which the Bragg gratings can be subjected to cold. The optical wave guide structure and the heating device or the cooling device are arranged at the end of the exhaust gas channel at a distance from an outlet of the exhaust gas into the surroundings of the device.

Abstract: A system is disclosed, including: a plurality of Bragg gratings distributed in positions transversely to the direction of flow of an exhaust gas in an exhaust gas channel of the device; an optical wave guide structure including at least one optical wave guide and in which the Bragg gratings are embodied; a heating device arranged adjacently to the Bragg gratings and through which the Bragg gratings are subjected to heat, or a cooling device arranged adjacently to the Bragg gratings, through which the Bragg gratings are subjected to cold; at least one light source for irradiating light into the optical wave guide structure; and at least one signal processing device which determines, from light backscattered from Bragg gratings in the optical wave guide structure against its original direction of diffusion, the speed of the flow of the exhaust gas.

Abstract: A gas turbine with at least one stationary stator blade and at least one rotor blade that can be rotated during operation is provided. The gas turbine has at least one optical waveguide embedded into a first rotor blade. The optical waveguide is oriented such that thermal radiation of a region of the first stator blade can be detected by the optical waveguide. An analyzing device is designed to analyze the thermal radiation and to ascertain the temperature of the region of the first stator blade, the temperature being ascertainable along a path from which the radiation is emitted during the rotation of the first rotor blade.

Abstract: A temperature sensor arrangement for gas turbines is provided. The temperature sensor arrangement has a measuring probe. The measuring probe has a bore in which a steel tube is guided so as to be axially movable. The steel tube includes a glass fibre having Bragg grating measurement points for measuring the temperature. Elongate measurement openings enable hot gas to flow through the measuring probe, flowing round the steel tube in the region of the Bragg grating.

Abstract: A fiber-optic vibration sensor for generators in power stations is disclosed. The sensor includes an optical fiber which has a freestanding end, wherein the freestanding end is caused to oscillate under the influence of vibrations, and the resulting oscillations are detected as a measure for the vibrations. Only the net weight of the optical fiber serves as a centrifugal mass.

Abstract: A wind energy installation is disclosed. The wind energy installation includes a rotor with at least one rotor blade. The wind energy installation includes at least one wind speed measuring system. The at least one wind speed measuring system optically measures the vibrations of an optical fiber due to vortex shedding.

Abstract: A rotor blade of a wind energy installation has a wall forming an outer shell, and at least one pressure measurement device arranged inside the rotor blade. The pressure measurement device includes a hollow body that is closed in a gastight fashion and has at least one pressure-dependent deformable diaphragm. At least one optical strain sensor is non-positively connected to each diaphragm. In a method using the pressure measurement device, the wind force is determined at wind energy installations by an evaluation unit which determines a comparison value indicating the difference between the pressure at the side of the outer shell facing the wind and the pressure at the side of the outer shell averted from the wind. A measured value for the wind force acting on the rotor blade is determined from the comparison value. The method can be used for optimized operation and/or protection of wind energy installations.

Abstract: A device for generating exhaust gas including a exhaust gas channel and a system. The system includes: a plurality of Bragg gratings distributed in positions transversely to the direction of flow of an exhaust gas at the end of the exhaust gas channel; an optical wave guide structure includes at least one optical wave guide and the Bragg gratings; and a heating device arranged adjacently to the Bragg gratings and through which the Bragg gratings are subjected to heat, or a cooling device arranged adjacently to the Bragg gratings, through which the Bragg gratings can be subjected to cold. The optical wave guide structure and the heating device or the cooling device are arranged at the end of the exhaust gas channel at a distance from an outlet of the exhaust gas into the surroundings of the device.

Abstract: A system is disclosed, including: a plurality of Bragg gratings distributed in positions transversely to the direction of flow of an exhaust gas in an exhaust gas channel of the device; an optical wave guide structure including at least one optical wave guide and in which the Bragg gratings are embodied; a heating device arranged adjacently to the Bragg gratings and through which the Bragg gratings are subjected to heat, or a cooling device arranged adjacently to the Bragg gratings, through which the Bragg gratings are subjected to cold; at least one light source for irradiating light into the optical wave guide structure; and at least one signal processing device which determines, from light backscattered from Bragg gratings in the optical wave guide structure against its original direction of diffusion, the speed of the flow of the exhaust gas.

Abstract: A method determines the layer thickness of a TBC coating of at least one blade of a non-positive-displacement machine. To this end, at least one electromagnetic wave is emitted to the surface of the at least one blade, the at least one electromagnetic wave is then at least partially reflected by the at least one blade, and the reflected portion of the at least one electromagnetic wave is received and subsequently processed. In addition, the at least one electromagnetic wave is emitted with a frequency matched to the layer thickness of the TBC coating, and the phase of the at least one electromagnetic wave is compared with the phase of the at least one received electromagnetic wave. The at least one emitted electromagnetic wave undergoes a phase change during reflection and the layer thickness of the TBC coating is determined by the phase comparison.

Abstract: A flowmeter determines the flow direction of a fluid. The flowmeter has a measuring element, around which the fluid flows and which comprises at least one fiber-optic cable and at least two electrical heating elements that lie adjacent to the fiber-optic cable(s) by a respective heat stream emanating from the respective heating element and directed towards at least one fiber-optic cable, the directions of the heat streams being at least proportionately reversed. In addition, the values of the individual heat streams can be influenced to different extents, depending on the flow direction of the fluid. An electromagnetic wave that can be coupled into the fiber-optic cable(s) can also be influenced according to the temperature of the fiber-optic cable(s).

Abstract: For a temperature measurement in areas having electromagnetic fields, shielding devices must be provided. According to the proposed technique, at least one temperature sensor is designed as a fiber-optic sensor having Bragg gratings (FBG), wherein the sensor is arranged in a non-metallic housing that precludes or minimizes expansion effects for the individual FBG sensors. For example, the proposed technique can be used advantageously to measure the temperature distribution in oil sand deposits, for which purpose a suitable measuring arrangement is required.

Abstract: A fiber-optic vibration sensor for generators in power stations is disclosed. The sensor includes an optical fiber which has a freestanding end, wherein the freestanding end is caused to oscillate under the influence of vibrations, and the resulting oscillations are detected as a measure for the vibrations. Only the net weight of the optical fiber serves as a centrifugal mass.

Abstract: A device for determining distance between a rotor blade and a wall of a gas turbine surrounding the rotor blade is provided. A waveguide guides and emits electromagnetic waves of at least one frequency in the direction of the rotor blade through a waveguide opening facing the rotor blade. The electromagnetic waves are injected into the waveguide and reflected portions of the electromagnetic waves are received. An evaluation unit compares the phase of the electromagnetic waves to be injected with the phase of the reflected portions of the electromagnetic waves and determines phase comparison values for every frequency and the distance is determined based on the phase comparison values. The waveguide comprises a sealing element which is configured to be transmissible for the electromagnetic waves of the frequency and which has two opposite surfaces in the direction of guidance of the electromagnetic waves.

Abstract: A wind energy installation is disclosed. The wind energy installation includes a rotor with at least one rotor blade. The wind energy installation includes at least one wind speed measuring system. The at least one wind speed measuring system optically measures the vibrations of an optical fiber due to vortex shedding.

Abstract: A pyrometer for gas turbines is provided. Incident thermal radiation is split between a plurality of optical wave guides by a reflection prism and a lens according to regions on the surface of a turbine blade. The pyrometer is built into the wall of the turbine without protruding and enables the simultaneous and parallel measurement of the temperature of a plurality of regions on the surface of the turbine blade when a spectrum of the heat radiation is largely maintained.

Abstract: A method of non-destructively testing a work piece is disclosed, wherein the work piece is placed within an active field of a positioning system; a frame of reference of the work piece is established based on the geometry of the work piece in the coordinates of the positioning system; the geometry of the work piece is detected by determining the position of specific transponders, which are fixed to the work piece, by the positioning system or the geometry of the work piece is detected by scanning at least parts of the contour of the work piece with a transponder of the positioning system; testing data is acquired for the work piece with a non-destructive testing probe, which comprises a transponder of the positioning system, while the position of the testing probe is recorded by the positioning system; the position of the testing probe is transformed into an intrinsic position defined with respect to the frame of reference of the work piece; and the intrinsic position of the testing probe is assigned to the t

Abstract: A device for determining distance between a rotor blade and a wall of a gas turbine surrounding the rotor blade is provided. A waveguide guides and emits electromagnetic waves in the direction of the rotor blade through a waveguide opening facing the rotor blade. The electromagnetic waves are injected into the waveguide and reflected portions of the electromagnetic waves are received. An evaluation unit compares the phase of the electromagnetic waves to be injected with the phase of the reflected portions of the electromagnetic waves and determines phase comparison values for every frequency and the distance is determined based on the phase comparison values. The waveguide includes two waveguide segments made from different materials having temperature stability and damping capacity increasing in the direction from the segment connected to the unit for injecting the waves to the segment having the waveguide opening.