Abstract: A system (8) for monitoring a high-temperature region of interest in a turbine engine (10) is provided. The system includes an internally cooled stationary vane (12) located in a path of a working gas of the turbine. A monitoring port (14) is located in the stationary vane. A monitoring instrument (16) is operatively connected to the monitoring port of the stationary vane to provide a field of view of the region of interest.

Abstract: A method for monitoring a high-temperature region of interest in a turbine engine (10) is provided. The method includes providing an internally-cooled stationary vane (12). The method may further include locating at least one monitoring port (14) in the stationary vane and operatively connecting a monitoring instrument (16) to the monitoring port to provide a field of view of a region of interest.

Abstract: A diagnostic system and method for monitoring operating conditions of turbine machine components (18, 19, 22, 23) that comprise one or more non-contact sensors (24, 31) that detect an operating condition of a turbine component (18, 19, 22, 23) over a defined region of the component. In addition, point sensors (50) are provided that detect and monitor the same operating condition within the defined region. Data generated from the point sensor (50) is used to calibrate the non-contact sensor (24, 31) and the data generated by the non-contact sensor (24, 31).

Abstract: A turbine airfoil can be formed with features to facilitate measurement of its wall thickness. An outer wall of the airfoil can include an outer surface and an inner surface. The outer surface of the airfoil can have an outer inspection target surface, and the inner surface of the airfoil can have an inner inspection target surface. The inner and outer target surfaces can define substantially flat regions in surfaces that are otherwise highly contoured. The inner and outer inspection target surfaces can be substantially aligned with each other. The inner and outer target surfaces can be substantially parallel to each other. As a result of these arrangements, a highly accurate measurement of wall thickness can be obtained. In one embodiment, the outer inspection target surface can be defined by an innermost surface of a groove formed in the outer surface of the outer wall of the airfoil.

Abstract: Apparatus and method for temperature mapping a rotating component (12) in a high temperature combustion environment. The apparatus includes a thermal imager (14) having a field of view to sense infrared (IR) emissions. Emissivity of a surface of the component is subject to variation in the combustion environment. A radiance emitter (18) defines a spot within the field of view of the thermal imager. The spot indicates a respective emissivity value. A processor (30) is connected to the thermal imager to generate a radiance map of the component based on the IR emissions from the component. The processor includes a thermal calibration module configured to calibrate the radiance map based on the emissivity value of the spot within the field of view of the thermal imager to generate a calibrated thermal map of the component that displays absolute temperature over the surface of the component.

Abstract: An imaging system for on-line imaging of a component in a gas turbine engine. The imaging system includes a flexible imaging bundle formed by a plurality of optical elements. An imaging end of the optical elements images a component in a hot gas path of the engine during operation of the engine and a viewing end provides an image of the component at a location displaced from the hot gas path. The optical elements are surrounded by a flexible metal sheath that is permeable to air to provide cooling air the optical elements from an air source surrounding the flexible imaging bundle.

Abstract: Apparatus and method for temperature mapping a rotating component (12) in a high temperature combustion environment. The apparatus includes a thermal imager (14) having a field of view to sense infrared (IR) emissions. Emissivity of a surface of the component is subject to variation in the combustion environment. A radiance emitter (18) defines a spot within the field of view of the thermal imager. The spot indicates a respective emissivity value. A processor (30) is connected to the thermal imager to generate a radiance map of the component based on the IR emissions from the component. The processor includes a thermal calibration module configured to calibrate the radiance map based on the emissivity value of the spot within the field of view of the thermal imager to generate a calibrated thermal map of the component that displays absolute temperature over the surface of the component.

Abstract: A method of remotely monitoring the radiant energy (6) emitted from a turbine component such as a turbine blade (1) having a low-reflective surface coating (3) which may be undergoing potential degradation is used to determine whether erosion, spallation, delamination, or the like, of the coating (3) is occurring.

Abstract: A method of remotely monitoring the radiant energy (6) emitted from a turbine component such as a turbine blade (1) having a low-reflective surface coating (3) which may be undergoing potential degradation is used to determine whether erosion, spallation, delamination, or the like, of the coating (3) is occurring.

Abstract: A hand-held thermography system (8). A generator (10) supplies current to a transformer (15) in a handle (16). An induction coil (20) connected to the transformer (15) extends from the handle (16). The induction coil (20) induces eddy currents in a test object (50), producing a thermal topography on a surface (52) of the object (50) that reveals structural features including defects in the object. An infrared camera (24) mounted on the transformer (16) digitizes images of the thermal topography. A controller (12) processes the images, displays them on a monitor (14), and stores them in a digital memory (11) for evaluation. Digitized positional data relating the position of the image to the surface may also be stored. An operator (40) presses a trigger (17), signaling the controller (12) to start current to the induction coil (20) and simultaneously to acquire and process one or more images from the camera (24).

Abstract: Aspects of the invention are directed to a visual-based system and method for non-destructively evaluating an uncoated turbine engine component. Aspects of the invention are well suited for high speed, high temperature components. Radiant energy emitted from an uncoated turbine engine component can be captured remotely and converted into a useful form, such as a high resolution image of the component. A plurality of images of the component can be captured over time and evaluated to identify failure modes. The system can also measure and map the temperature and/or radiance of the component. The system can facilitate the non-destructive evaluation of uncoated turbine components during engine operation without disassembly of the engine, thereby providing significant time and cost savings. Further, the system presents data to a user with sufficient context that allows an engine operator can evaluate the information with an increased degree of confidence and certainty.

Abstract: A hand-held thermography system (8). A generator (10) supplies current to a transformer (15) in a handle (16). An induction coil (20) connected to the transformer (15) extends from the handle (16). The induction coil (20) induces eddy currents in a test object (50), producing a thermal topography on a surface (52) of the object (50) that reveals structural features including defects in the object. An infrared camera (24) mounted on the transformer (16) digitizes images of the thermal topography. A controller (12) processes the images, displays them on a monitor (14), and stores them in a digital memory (11) for evaluation. Digitized positional data relating the position of the image to the surface may also be stored. An operator (40) presses a trigger (17), signaling the controller (12) to start current to the induction coil (20) and simultaneously to acquire and process one or more images from the camera (24).

Abstract: A method for non-destructive evaluation of an article of manufacture (30) by coating the article with a temperature-sensitive coating (34), stimulating the article with energy (18) to induce temperature changes in the article responsive to features of the article, then evaluating (24) a resulting topography of energy-induced changes (50, 52, 53) in the coating (34). The energy imparted to the article may be, for example, electromagnetic, magnetic, or sonic energy that produces localized changes in temperature in the article (30) in response to features (32) of the article such as flaws or other discontinuities. The coating (34) may be a suspension of liquid crystals in a liquid, and the energy may be an application of sonic energy. The coating may be a material that hardens (42, 54) or softens (44, 56) upon a slight increase in temperature. Layers (34, 35) of different energy-sensitive coatings (38, 40) may be applied to indicate different aspects of features of the article.

Abstract: A joint having bond line grains that nucleate in the joint region and grow into the adjoined solid substrates. The resulting bond line grains have a size that is greater than a thickness of a molten region. The surfaces of the substrates are cold worked to a desired degree of residual stress prior to the bonding process so that the recrystallization of the substrate surface necessary for the grains to grow into the substrates results in a reduction in the local free energy.

Abstract: A defect detection system for thermally imaging a structure that has been energized by a sound energy. The system includes a transducer that couples a sound signal into the structure, where the sound signal causes defects in the structure to heat up. In one embodiment, the sound signal has one or more frequencies that are at or near an eigen-mode of the structure.

Abstract: Method for welding objects having limited backside access to a cavity behind a region to be welded. The method includes inserting a fugitive backing material in an installation state into a first portion of the cavity proximate the region to be welded and then transforming the fugitive backing material to a rigid state. The method further includes forming a weld in the region and then transforming the fugitive backing material to a removable state and removing the fugitive backing material from the cavity. The method may also include placing a pre-formed weld backing in the cavity and filling the cavity with a fugitive backing material. The method further includes transforming the fugitive backing material to a rigid state, forming a weld, and transforming the fugitive backing material to a removable state. The method may further include removing the fugitive backing material and removing the pre-formed weld backing from the cavity.

Abstract: A defect detection system for thermally imaging a structure that has been energized by a sound energy. The system includes a transducer that couples a sound signal into the structure, where the sound signal causes defects in the structure to heat up. In one embodiment, a non-linear coupling material is positioned between the transducer and the structure to couple the sound energy from the transducer to the structure. A predetermined force is applied to the transducer and a pulse duration and a pulse frequency of the sound signal are selected so that the sound energy induces acoustic chaos in the structure, thus generating increased thermal energy. A thermal imaging camera images the structure when it is heated by the sound signal.

Abstract: An apparatus (10) for performing acoustic thermography including a fixture (32) having a compliant member (40) that allows contacting surfaces of a horn face (20) and a specimen surface (16) to self-align into parallel contact in response to only the contacting force (FC) there between. When the contacting surfaces are brought together in a slightly non-parallel alignment, the contacting force develops a force component (FN) that is normal to the plane of contact. This normal force causes deflection of a compliant member, thereby providing movement that brings the contacting surfaces into parallel alignment. The compliant member may be a spring (48), elastomer (50), swivel member (56), bearing member (80), or a curved non-stick surface (90) in various embodiments.

Abstract: A defect detection system for thermally imaging a structure that has been energized by a sound energy. The system includes a transducer that couples a sound signal into the structure, where the sound signal causes defects in the structure to heat up. In one embodiment, the sound signal has one or more frequencies that are at or near an eigen-mode of the structure. In another embodiment, an on-linear coupling material is positioned between the transducer and the structure to couple the sound energy from the transducer to the structure. A predetermined force is applied to the transducer and a pulse duration and a pulse frequency of the sound signal are selected so that the sound energy induces acoustic chaos in the structure, thus generating increased thermal energy. A thermal imaging camera images the structure when it is heated by the sound signal.

Abstract: An apparatus (10) for performing acoustic thermography including a fixture (32) having a compliant member (40) that allows contacting surfaces of a horn face (20) and a specimen surface (16) to self-align into parallel contact in response to only the contacting force (FC) there between. When the contacting surfaces are brought together in a slightly non-parallel alignment, the contacting force develops a force component (FN) that is normal to the plane of contact. This normal force causes deflection of a compliant member, thereby providing movement that brings the contacting surfaces into parallel alignment. The compliant member may be a spring (48), elastomer (50), swivel member (56), bearing member (80), or a curved non-stick surface (90) in various embodiments.