Abstract: A blade vibration monitor backpressure limiting system (BVMBLS), that in addition to direct blade vibration and condenser backpressure monitoring utilizes other plural types of other parallel, real time monitored power plant operation state (OS) information that influences blade vibration. The system references previously stored information in an information storage device that associates respective types of monitored OS information with blade vibration. The BVMBLS determines in real time a likelihood of whether any of the monitored operation states, alone or in combination with other types of monitored operation states, is indicative of a turbine blade vibration safe operation (SO). The BVMBLS determination is utilized to increase or reduce power generation load incrementally so that power efficiency and maximum load is enhanced while turbine blade vibration is maintained in a safe operation state. The previously stored information is updated to new association information.

Abstract: A blade vibration monitor backpressure limiting system (BVMBLS), that in addition to direct blade vibration and condenser backpressure monitoring utilizes other plural types of other parallel, real time monitored power plant operation state (OS) information that influences blade vibration. The system references previously stored information in an information storage device that associates respective types of monitored OS information with blade vibration. The BVMBLS determines in real time a likelihood of whether any of the monitored operation states, alone or in combination with other types of monitored operation states, is indicative of a turbine blade vibration safe operation (SO). The BVMBLS determination is utilized to increase or reduce power generation load incrementally so that power efficiency and maximum load is enhanced while turbine blade vibration is maintained in a safe operation state. The previously stored information is updated to new association information.

Abstract: A generator stator core through-bolt tensioning device that automatically tightens the nut on the through-bolts that hold together and compress laminate plates of the stator core in a high voltage generator. A controller receives a signal from a measuring device, such as a fiber Bragg grating that measures the strain on the bolt, and based on that signal determines whether the nut needs to be tightened. If the controller determines that tightening is necessary, it will cause the tensioning device to automatically tighten the nut while the generator is in service, and use the measuring device to provide feedback of the tensioning of the through-bolt to know when to stop the device from tightening the nut.

Abstract: Apparatus (12) to measure blade vibration in a gas turbine engine (8). An illumination source (20) generates a sequence of illumination bursts in a field of view capturing a passing rotating blade (10) of the gas turbine engine. An imager (22) generates image data including a series of images capturing views of the passing rotating blade. The images are exposed in response to respective illumination bursts. A controller (30) is configured to process the series of images to identify one or more vibration modes of the rotating blade.

Abstract: A generator stator core that includes a plurality of through-bolts extending through the stator core. Each through-bolt includes a threaded end on which is positioned a conical washer and a through-bolt nut, where the through-bolt nuts are tightened against the washers to compress laminate plates and hold the stator core together. The stator core further includes a through-bolt tension monitoring system including a fiber Bragg grating sensor mounted to one or more of the conical washers and being provided in at least one optical fiber. The monitoring system further includes a monitoring device providing an optical signal to each of the fiber Bragg grating sensors and receiving a reflected signal from the fiber Bragg grating sensors where the reflected signal provides an indication of strain on the washer to provide an indication of how tight the nut is on the through-bolt.

Abstract: A generator stator core through-bolt tensioning device that automatically tightens the nut on the through-bolts that hold together and compress laminate plates of the stator core in a high voltage generator. A controller receives a signal from a measuring device, such as a fiber Bragg grating that measures the strain on the bolt, and based on that signal determines whether the nut needs to be tightened. If the controller determines that tightening is necessary, it will cause the tensioning device to automatically tighten the nut while the generator is in service, and use the measuring device to provide feedback of the tensioning of the through-bolt to know when to stop the device from tightening the nut.

Abstract: A sensor includes a housing adapted to be secured to a component within a system to be monitored by the sensor, an optical fiber, and a membrane spring assembly. The optical fiber includes a sensing portion containing a fiber Bragg grating that is able to undergo expansion and contraction resulting from movement of the optical fiber at a second location relative to a first location. The membrane spring assembly includes a membrane disc, wherein movement of a central portion thereof causes corresponding displacement of the optical fiber at the second location to cause expansion and contraction of the sensing portion of the optical fiber containing the fiber Bragg grating, which expansion and contraction effects a change in a light wavelength reflected by the fiber Bragg grating. The light wavelength reflected by the fiber Bragg grating can be used to measure movement of the central portion of the membrane disc.

Abstract: A method of matching sensors in a multi-probe blade vibration monitor for a turbine. The method includes providing at least two probes mounted in a casing of the turbine adjacent to a rotating blade structure of the turbine. Targets are provided on radially outer portions of the blade structure. Each of the probes includes a sensor generating signals corresponding to target passing events, and a set of synchronous harmonics of the rotational speed of the rotor are produced for each sensor. The position of the sensors is adjusted such that the sets of harmonics of the sensors are substantially matched, indicating that the positions of the sensors are matched.

Abstract: A method is provided for monitoring velocity of a fluid flow through a predetermined fluid flow space. A fiber optic conductor includes a flow measurement portion defining an elongated dimension extending across a portion of the fluid flow space. The fluid flow in the fluid flow space causes the measurement portion of the fiber optic conductor to flex in a direction transverse to the elongated dimension. Optical radiation is supplied to the fiber optic conductor, and optical radiation is received from the fiber optic conductor after the supplied optical radiation has passed through the measurement portion. The received optical radiation is analyzed to effect a determination of a flow velocity of the fluid flow.

Abstract: A method is provided for monitoring velocity of a fluid flow through a predetermined fluid flow space. A fiber optic conductor includes a flow measurement portion defining an elongated dimension extending across a portion of the fluid flow space. The fluid flow in the fluid flow space causes the measurement portion of the fiber optic conductor to flex in a direction transverse to the elongated dimension. Optical radiation is supplied to the fiber optic conductor, and optical radiation is received from the fiber optic conductor after the supplied optical radiation has passed through the measurement portion. The received optical radiation is analyzed to effect a determination of a flow velocity of the fluid flow.

Abstract: A system and method for monitoring the condition of a vibration sensor in a system. Vibrations are received in the system at one or more vibration sensors. Sensor data is output by the vibration sensor(s). The sensor data includes data representative of the vibrations in the system and data representative of a natural frequency of the corresponding vibration sensor. The sensor data output from the vibration sensor(s) is monitored, and upon a change in the data representative of the natural frequency of a vibration sensor, that vibration sensor is flagged.

Abstract: Apparatus (12) to measure blade vibration in a gas turbine engine (8). An illumination source (20) generates a sequence of illumination bursts in a field of view capturing a passing rotating blade (10) of the gas turbine engine. An imager (22) generates image data including a series of images capturing views of the passing rotating blade. The images are exposed in response to respective illumination bursts. A controller (30) is configured to process the series of images to identify one or more vibration modes of the rotating blade.

Abstract: A magnetic flux sensor for measuring the radial component of the magnetic flux impinging on a stator bar of a high voltage generator. The magnetic flux sensor includes a fiber Bragg grating formed in an optical fiber and enclosed within a magnetostrictive coating. The magnetostrictive coating responds to changes in magnetic flux by applying a strain on the fiber that changes the reflected wavelength of the Bragg grating that can be measured to provide a measurement of the flux. In one embodiment, one or more of the magnetic flux sensors is positioned directly within an insulating layer of the particular stator bar.

Abstract: A component sensing system for monitoring the condition of ceramic tiles in a combustion chamber of a gas turbine engine. The sensing system includes an optical fiber that is mounted to the component being monitored, for example, the ceramic tiles in the gas turbine combustion chamber. The optical fiber can be formed in any suitable orientation or configuration, such as a meandering or serpentine orientation. The fiber is optically coupled to a Brillouin signal analyzer that provides an optical pulse to the sensing section of the fiber and detects Brillouin backscattering from the fiber as the pulse travels along the fiber. The frequency of the Brillouin backscattering signal is monitored relative to the distance along the sensing section of the fiber. A rise in temperature at a location of the fiber shows up in the analyzer as an increase in frequency of the backscattered signal.

Abstract: A method is provided for monitoring velocity of a fluid flow through a predetermined fluid flow space. A fiber optic conductor includes a flow measurement portion defining an elongated dimension extending across a portion of the fluid flow space. The fluid flow in the fluid flow space causes the measurement portion of the fiber optic conductor to flex in a direction transverse to the elongated dimension. Optical radiation is supplied to the fiber optic conductor, and optical radiation is received from the fiber optic conductor after the supplied optical radiation has passed through the measurement portion. The received optical radiation is analyzed to effect a determination of a flow velocity of the fluid flow.

Abstract: A sensor includes a housing adapted to be secured to a component within a system to be monitored by the sensor, an optical fiber, and a membrane spring assembly. The optical fiber includes a sensing portion containing a fiber Bragg grating that is able to undergo expansion and contraction resulting from movement of the optical fiber at a second location relative to a first location. The membrane spring assembly includes a membrane disc, wherein movement of a central portion thereof causes corresponding displacement of the optical fiber at the second location to cause expansion and contraction of the sensing portion of the optical fiber containing the fiber Bragg grating, which expansion and contraction effects a change in a light wavelength reflected by the fiber Bragg grating. The light wavelength reflected by the fiber Bragg grating can be used to measure movement of the central portion of the membrane disc.

Abstract: A system and method for monitoring the condition of a vibration sensor in a system. Vibrations are received in the system at one or more vibration sensors. Sensor data is output by the vibration sensor(s). The sensor data includes data representative of the vibrations in the system and data representative of a natural frequency of the corresponding vibration sensor. The sensor data output from the vibration sensor(s) is monitored, and upon a change in the data representative of the natural frequency of a vibration sensor, that vibration sensor is flagged.

Abstract: A method for measuring the differential emissivity between two sites on the surface of a body and the temperature of the two sites. The method includes a plurality of measurements of the infrared radiation arising from each of the two sites under a number of different conditions. Some of the measurements include irradiation by external infrared radiation at a known wavelength and intensity. The infrared radiation arising from each of the sites may include emitted radiation, reflected ambient radiation, and reflected external radiation. Additionally, the temperature determined using the method described can be used to calibrate infrared imaging devices used to inspect the entire body.

Abstract: A method and apparatus for monitoring blade vibrations in a turbine engine having blade tip target portions associated with blades. An illumination conduit including a plurality of optical fibers conveys light from a light source to a transmission end of the optical fibers where the light is focused to define an axially elongated projected image. The blade tip target portions pass through the projected image and reflect light to a receptor array defined by receptor ends of a plurality of optical fibers forming an imaging conduit for conveying the reflected light to a sensor array. An imaging end of the imaging conduit radiates an image onto the sensor array that is identical to the reflected light image received at the receptor array to track tangential and axial movement of a predetermined point on the target portion.

Abstract: A method and apparatus for monitoring blade vibrations in a turbine engine having blade tip target portions associated with blades. An illumination conduit including a plurality of optical fibers conveys light from a light source to a transmission end of the optical fibers where the light is focused to define an axially elongated projected image. The blade tip target portions pass through the projected image and reflect light to receptor ends of a plurality of optical fibers defining a detection conduit for conveying the reflected light to a processor. The transmission ends and receptor ends of the optical fibers are configured as a narrow rectangle to define a probe end for receiving reflected light at different axial locations along the probe end, and to detect blade passing events defined by passage of either or both a blade leading edge and a blade trailing edge.