Patent Application
20170199087
The subject matter disclosed herein relates to strain sensors and, more specifically, to components with strain sensors and thermally reactive features and methods for monitoring the same.
Some components may need to operate in environments comprising elevated temperatures and/or corrosive conditions. For example, in gas turbine engines, such as aircraft engines for example, air is drawn into the front of the engine, compressed by a shaft-mounted rotary-type compressor, and mixed with fuel. The mixture is burned, and the hot exhaust gases are passed through a turbine mounted on a shaft. The flow of gas turns the turbine, which turns the shaft and drives the compressor and fan. The hot exhaust gases flow from the back of the engine, driving it and the aircraft forward.
During operation of gas turbine engines, the temperatures of combustion gases may exceed 3,000° F., considerably higher than the melting temperatures of the metal parts of the engine which are in contact with these gases. Operation of these engines at gas temperatures that are above the metal part melting temperatures may depend in part one or more protective coatings and/or on supplying a cooling air to the outer surfaces of the metal parts through various methods. The metal parts of these engines that are particularly subject to high temperatures, and thus require particular attention with respect to cooling, are the metal parts forming combustors and parts located aft of the combustor.
Moreover, these and other components may experience stress and/or strain from various forces over its operational lifecycle experiences fluctuations in operating temperatures. While various tools may be utilized to measure imparted stress and strain in relatively standard environments, turbine and other components in may experience working conditions with temperature fluctuations that may impact one or more component properties.
Accordingly, alternative components with strain sensors and thermally reactive features and methods for monitoring the same would be welcome in the art.
In one embodiment, a component is disclosed. The component can a substrate, a strain sensor comprising at least two reference points disposed on the substrate, and one or more thermally reactive features disposed on the substrate proximate the strain sensor, wherein the one or more thermally reactive features react to one or more elevated temperatures.
In another embodiment, another component is disclosed. The component can comprise a substrate, and a strain sensor comprising at least two reference points disposed on the substrate, wherein the strain sensor comprises a thermally reactive feature that reacts to one or more elevated temperatures.
In yet another embodiment, a method for monitoring a component is disclosed. The method includes measuring a second distance between at least two reference points of a strain sensor on the component at a second time interval, comparing the second distance between the at least two reference points of the strain sensor to a first distance between the at least two reference points of the strain sensor from a first time interval to determine a strain between the first time interval and the second time interval, determining an exposed elevated temperature between the first time interval and the second time interval based on a reaction of one or more thermally reactive features disposed on the component proximate the strain sensor, and referencing the exposed elevated temperature to the strain.
These and additional features provided by the embodiments discussed herein will be more fully understood in view of the following detailed description, in conjunction with the drawings.
The embodiments set forth in the drawings are illustrative and exemplary in nature and not intended to limit the inventions defined by the claims. The following detailed description of the illustrative embodiments can be understood when read in conjunction with the following drawings, where like structure is indicated with like reference numerals and in which:
One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
When introducing elements of various embodiments of the present invention, the articles “a,” “an,” “the,” and “said” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Referring now to
The component 10 (and more specifically the substrate 11 of the overall component 10) can comprise a variety of types of components used in a variety of different applications, such as, for example, components utilized in high temperature applications (e.g., components comprising nickel or cobalt based superalloys). In some embodiments, the component 10 may comprise an industrial gas turbine or steam turbine component such as a combustion component or hot gas path component. In some embodiments, the component 10 may comprise a turbine blade, compressor blade, vane, nozzle, shroud, rotor, transition piece or casing. In other embodiments, the component 10 may comprise any other component of a turbine such as any other component for a gas turbine, steam turbine or the like. In some embodiments, the component may comprise a non-turbine component including, but not limited to, automotive components (e.g., cars, trucks, etc.), aerospace components (e.g., airplanes, helicopters, space shuttles, aluminum parts, etc.), locomotive or rail components (e.g., trains, train tracks, etc.), structural, infrastructure or civil engineering components (e.g., bridges, buildings, construction equipment, etc.), and/or power plant or chemical processing components (e.g., pipes used in high temperature applications).
Referring now to
As best illustrated in
Furthermore, the dimensions of the strain sensor 40 may depend on, for example, the component 10, the location of the strain sensor 40, the targeted precision of the measurement, deposition technique, and optical measurement technique. For example, in some embodiments, the strain sensor 40 may comprise a length and width ranging from less than 1 millimeter to greater than 300 millimeters. Moreover, the strain sensor 40 may comprise any thickness that is suitable for deposition and subsequent optical identification without significantly impacting the performance of the underlying component 10. For example, in some embodiments, the strain sensor 40 may comprise a thickness of less than from about 0.1 millimeters to greater than 1 millimeter. In some embodiments, the strain sensor 40 may have a substantially uniform thickness. Such embodiments may help facilitate more accurate measurements for subsequent strain calculations between the first and second reference points 41 and 42.
In some embodiments, the strain sensor 40 may comprise any configurations such as a positively deposited square or rectangle wherein the first and second reference points 41 and 42 comprise two opposing sides of said square or rectangle. In other embodiments, the strain sensor 40 may comprise at least two deposited reference points 41 and 42 separated by negative space 45 (i.e., an area in which ceramic material 30 is not deposited). The negative space 45 may comprise, for example, an exposed portion 12 of the exterior surface of the component 10. Alternatively or additionally, the negative space 45 may comprise a coating that helps protect at least a portion of the substrate 11 and/or strain sensor 40.
As illustrated in
In some embodiments, the component 10 may further comprise a coating 50 disposed on the substrate 11 adjacent the strain sensor 40. The coating may be disposed between the substrate 11 and the strain sensor 40 and potentially between the substrate 11 and the one or more thermally reactive features 50. The coating may thereby help protect the substrate 11 from the operating environment of the component 10 (e.g., elevated temperatures in an industrial gas turbine) and/or help ensure adhesion for the strain sensor 40 and/or one or more thermally reactive features 50.
Referring now to
The component 10 can comprise any number of the one or more thermally reactive features 50. For example, the component 10 may comprise a single thermally reactive feature 50. The single thermally reactive feature 50 may react to a single temperature (e.g., changing colors or vanishing at a single temperature), or may gradually react over a range of temperatures (e.g., transition between two or more colors over a range of temperatures).
In some embodiments, the component 10 may comprise a first thermally reactive feature 51 that reacts at a first elevated temperature and a second reactive feature 52 that reacts to a second elevated temperature higher than the first elevated temperature. The component 10 may further comprise a third thermally reactive feature 53, fourth thermally reactive feature 54, fifth thermally reactive feature 55 and so on that react to third, fourth and fifth elevated temperatures respectively. In such embodiments, the thermally reactive features 50 may individually react to elevated temperatures spaced apart at certain intervals. Then, based on the thermally reactive features 50 did and did not react, one may be able to deduce the highest temperature that the strain sensor 40 was exposed to.
As exemplified in
In some embodiments, the one or more thermally reactive features 50 may comprise a plurality of thermally reactive features 50 separated from one another. For example, the one or more thermally reactive features 50 may be equally spaced along one or more sides of the strain sensor 40. In some embodiments, such as that illustrated in
In some embodiments, the one or more thermally reactive features 50 may be disposed on top of the strain sensor 40 or be integrated with the strain sensor 40. For example, the one or more thermally reactive features 50 may be disposed on top of a printed strain sensor 40.
Alternatively or additionally, the strain sensor 40 may comprise the thermally reactive feature 50 such as when the strain sensor 40 comprises a material that reacts to one or more elevated temperatures (e.g., changes colors). For example, the component 10 may comprise a substrate 11 and a strain sensor 40 comprising at least two reference points 41 and 42 disposed on the substrate 11, wherein the strain sensor 40 comprises the thermally reactive feature 50 that reacts to one or more elevated temperatures.
As discussed above, in some embodiments, the component 10 may comprise one or more coatings. For example, one or more coatings may be disposed between the substrate 11 and the strain sensor 40 and/or the thermally reactive features 50. In such embodiments, the coating may help ensure the integrity of the strain sensor 40 and/or thermally reactive features 50 during operation of the component 10.
The one or more thermally reactive features 50 may comprise any suitable material or materials that react to one or more elevated temperatures. In some embodiments, the one or more thermally reactive features 50 may comprise a thermally reactive ink or paint. For example, the one or more thermally reactive features 50 may comprise one or more commercially available thermochromic pigments that react at different temperatures. In some embodiments, the one or more thermally reactive features 50 may comprise one or more materials that bum, melt, ignite or otherwise vanish from the component 10 at one or more elevated temperatures.
The strain sensor 40 and one or more thermally reactive features 50 may be deposited in one or more of a variety of locations on the substrate 11. For example, if the substrate comprises a turbine component, the strain sensor 40 and one or more thermally reactive features 50 may be deposited on a turbine blade, compressor blade, vane, nozzle, shroud, rotor, transition piece or casing. In such embodiments, the strain sensor 40 and one or more thermally reactive features 50 may be deposited in one or more locations known to experience various forces during unit operation such as on or proximate airfoils, platforms, tips or any other suitable location. Moreover, since the strain sensor 40 is proximate the one or more thermally reactive features 50, the strain sensor 40 may be deposited on a hot gas path or combustion turbine component such that the one or more thermally reactive features 50 may help identify peak experienced operating temperatures.
In even some embodiments, multiple strain sensors 40 and one or more thermally reactive features 50 may be deposited on a single turbine component or on multiple turbine components. For example, a plurality of strain sensors 40 may be deposited on a single turbine component (e.g., a turbine blade) at various locations such that the strain may be determined at a greater number of locations about the individual turbine component. Alternatively or additionally, a plurality of like turbine components (e.g., a plurality of turbine blades), may each have a strain sensor 40 and one or more thermally reactive features 50 deposited in a standard location so that the amount of strain experienced by each specific turbine component may be compared to other like turbine components. In even some embodiments, multiple different turbine components of the same turbine unit (e.g., turbine blades and vanes for the same turbine) may each have a strain sensor 40 and one or more thermally reactive features 50 deposited thereon so that the amount of strain experienced at different locations within the overall turbine may be determined.
Referring additionally to
Still referring to
Finally, method 100 can comprise in step 140 referencing the exposed elevated temperature determined in step 130 with the strain determined in step 120. The reference in step 140 may help verify the integrity of the component 10, identify any extreme occurrences or deviations from standard operating conditions, and/or otherwise be used to diagnose or determine the future utility of the component 10.
It should now be appreciated that strain sensors and one or more thermally reactive features may be disposed on substrates to form overall components that can be monitored for strain, creep or the like. The one or more thermally reactive features may also enable the understanding of the exposed elevated temperatures experienced by the strain sensor 40 to help study, diagnose, and/or validate the overall component.
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
