Abstract:
One embodiment of the present invention is a unique system for measuring radiant energy in gas turbine engines, gas turbine engine components and gas turbine engine/component rigs. Another embodiment is a unique method for measuring radiant energy in gas turbine engines, gas turbine engine components and gas turbine engine/component rigs. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for measuring radiant energy. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application 61/291,545, filed Dec. 31, 2009, and is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to gas turbine engines, and more particularly, to systems and methods for measuring radiant energy in a gas turbine engine and gas turbine engine components and rigs. 
     BACKGROUND 
     The measurement of radiant energy in gas turbine engines, gas turbine engine components and rigs remains an area of interest. Some existing systems have various shortcomings, drawbacks, and disadvantages relative to certain applications. Accordingly, there remains a need for further contributions in this area of technology. 
     SUMMARY 
     One embodiment of the present invention is a unique system for measuring radiant energy in gas turbine engines, gas turbine engine components and gas turbine engine/component rigs. Another embodiment is a unique method for measuring radiant energy in gas turbine engine, gas turbine engine components and gas turbine engine/component rigs. Other embodiments include apparatuses, systems, devices, hardware, methods, and combinations for measuring radiant energy. Further embodiments, forms, features, aspects, benefits, and advantages of the present application shall become apparent from the description and figures provided herewith. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views, and wherein: 
         FIGS. 1A and 1B  schematically illustrates a non-limiting example of a system for measuring radiant energy in gas turbine engines, components and test rigs in accordance with an embodiment of the present invention. 
         FIGS. 2A and 2B  depict a non-limiting example of an optical collection element and a fiber-optic lead in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     For purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nonetheless be understood that no limitation of the scope of the invention is intended by the illustration and description of certain embodiments of the invention. In addition, any alterations and/or modifications of the illustrated and/or described embodiment(s) are contemplated as being within the scope of the present invention. Further, any other applications of the principles of the invention, as illustrated and/or described herein, as would normally occur to one skilled in the art to which the invention pertains, are contemplated as being within the scope of the present invention. 
     Referring now to the drawings, and in particular,  FIGS. 1A and 1B , a non-limiting example of a high temperature structure  10  in accordance with an embodiment of the present invention is depicted. In one form, structure  10  is a component of gas turbine engine, such as a combustion liner, a turbine blade, vane or wheel, or another gas turbine engine component. In other embodiments, structure  10  may be a high temperature test rig component or gas turbine engine component installed in a test rig. In still other embodiments, high temperature structure  10  may be a gas turbine engine. 
     In one form structure  10  is contained within another structure  12 , such as a test rig, a furnace, a gas turbine engine case structure or another gas turbine engine structure. In one form, structure  12  is pressurized. In other embodiments, structure  12  may not be pressurized. Structure  10  and structure  12  may take other forms in other embodiments, and may be components other than gas turbine engines and/or gas turbine engine components and/or gas turbine engine test rigs or components, unless specifically claimed herein. In one form, structure  10  is disposed in a fluid  14 , such as air or combustion products. In one form, fluid  14  is in motion, e.g., representative of the output of a gas turbine engine compressor, combustor and/or turbine. 
     The temperatures inside structure  12  are elevated, e.g., 600° F. or greater. In one form, the temperatures inside structure  12  are approximately 900° F. or greater. In a particular form, the temperatures inside structure  12  are approximately 1100° F. or greater. Structure  10  experiences high temperatures at various operating points. In one form, structure  10  has skin temperatures above 1500° F. In a particular form, structure  10  has skin temperatures in the range of 1800° F. to 2100° F. In other embodiments, structure  10  may have skin temperatures at higher and/or lower temperatures, e.g., including up to 3500° F. In one form, fluid  14  is at an elevated temperature, e.g., 600° F. or greater. In a particular form, fluid  14  is at a temperature of approximately 900° F. or greater. In a more particular form, the temperature of fluid  14  is approximately 1100° F. or greater. In other embodiments, the temperature of fluid  14  may be greater still, such as 1800° F. to 2100° F. or greater. 
     In various situations, e.g., during the testing or operation of a gas turbine engine or gas turbine engine components, it is desirable be able to determine surface temperatures and gas temperatures. In order to confirm the temperature at desired locations, i.e., areas of interest on structure  10  and/or areas of interest in fluid  14  locations, a system  20  for measuring radiant energy in accordance with an embodiment of the present invention may be employed. 
     System  20  includes a plurality of optical collection elements  22 , a plurality of fiber-optic leads  24 , a fiber channel selection switch  26 , a proximal lens  28 , an optical filter  30 , a detector  32 , a controller  34  and a display  36 . In the depicted example, a wall W separates structures  10  and  12  from fiber channel selection switch  26 , proximal lens  28 , optical filter  30 , detector  32 , controller  34  and display  36 . Optical collection elements  22  are disposed in structure  12  on the other side of wall W, and fiber-optic leads  24  are partially disposed on both sides of wall W, extending between optical collection elements  22  and fiber channel selection switch  26 . 
     Referring now to  FIGS. 2A and 2B , a non-limiting example of an optical collection element  22  in accordance with an embodiment of the present invention is depicted. Optical collection element  22  is operative to view an area of interest, e.g., on or in the vicinity of structure  10 . Optical collection element  22  includes a distal lens  38 , optical transmission elements  40  and a multi-part casing  42  for housing distal lens  38  and transmission elements  40 . Transmission elements  40  are in optical communication with distal lens  38  and fiber-optic lead  24 . As used herein, “optical communication” means that the components that are in optical communication are arranged and configured to transmit therebetween optical signals, i.e., electromagnetic (EM) waves, in the desired EM band. In one form, the desired EM band is infrared (IR) and near infrared (NIR) radiation. In other embodiments, other EM bands may be employed in addition to or in place of IR and NIR wavelengths. 
     Distal lens  38  is structured to view the area of interest and to collect raw optical image data therefrom, e.g., IR and NIR energy in the form of electromagnetic waves emanating from structure  10  and/or fluid  14 . In one form, distal lens  38  is a reflecting prism. In other embodiments, distal lens  38  may take other forms, for example, a transmitting prism or one or more other types of lenses. In one form, distal lens  38  is coated with a high temperature reflective coating. The coating is configured for operation at the temperatures inside structure  12  to which it is exposed. In one form, the coating is configured for operation at temperatures of at least 1100° F. In other embodiments, the coating may be configured for operation at higher temperatures. 
     Transmission elements  40  are configured to transmit the optical data received from distal lens  38  for reception by the distal end  44  of fiber-optic lead  24 . Fiber-optic lead  24  is disposed inside a shielding  46 . In one form, shielding  46  is a stainless steel tube. In other embodiments, shielding  46  may take other forms. Casing  42  is configured to receive and retain fiber-optic lead  24  and shielding  46 , and to align fiber-optic lead  24  with the optical path of transmission elements  40 . In one form, casing  42  is structured to focus the optical data received from distal lens  38 , e.g., by varying the distance between distal lens  38  and transmission elements  40 . In other embodiments, casing  42  may not be structured to perform a focusing function. Casing  42  includes an opening  48  for optically exposing distal lens  38  to the area of interest. 
     In one form, optical collection element  22  and fiber-optic lead  24  are uncooled. By being uncooled, smaller diameters of optical collection elements  22  and shielding  46  may be employed, and potential adverse impacts resulting from the introduction of cooling jacket gases into structure  12  are avoided. In other embodiments, optical collection element  22  and/or fiber-optic lead  24  may be cooled. For example, cooling air may be provided via one or more passages inside shielding  46 , which may be discharged into, for example, structure  12 . In the depiction of  FIG. 2A , an alternative embodiment of shielding  46  includes an inner annular wall  46 A and two annular passages  50  and  52  which may be used as supply and return passages for a cooling medium, such as air, without discharging the cooling medium inside structure  12 . 
     Fiber-optic lead  24  is operative to transmit the optical data received from transmission elements  40  for reception by proximal lens  28 . Fiber-optic lead  24  is configured for operation at elevated temperatures. In one form, fiber-optic lead  24  is configured for operation at temperatures up to 1100° F. In other embodiments, fiber-optic lead  24  may be configured for operation at temperatures up to 1800° F. to 2100° F. or greater. In one form, fiber-optic lead  24  is a fused silica coherent optical-fiber bundle. One commercially available fused silica coherent optical-fiber bundle that is suitable for use as fiber-optic lead  24  is available from Fujikura America, Inc. 
     Referring again to  FIGS. 1A and 1B , fiber channel selection switch  26  includes a terminal plate  54  and an output plate  56 . Terminal plate  54  includes a plurality of terminals  58 . Terminals  58  are operative to receive and mechanically couple the proximal end  60  of fiber-optic leads  24  to fiber channel selection switch  26 . Output plate  56  includes an image output port  62 . In one form, image output port is operative to transmit the optical data from fiber-optic lead  24  to proximal lens  28 . In one form, image output port  62  is operative to transmit optical data from a single fiber-optic lead  24 . In other embodiments, image output port  62  is operative to transmit optical data from a plurality of fiber-optic leads. In one form, output plate  56  is structured to mount proximal lens  28  in image output port  62 . In other embodiments, other arrangements for mounting proximal lens  28  may be employed. In various embodiments, image output port  62  may take different forms, and may be, for example, an optical pathway, or may simply be an opening in output plate  56  that permits proximal lens  28  to be in close proximity to the desired fiber-optic lead  24 . 
     Fiber channel selection switch  26  is structured to selectively expose output port  62  to a chosen fiber-optic lead  24  in response to a control input. In various embodiments, fiber channel selection switch  26  is structured to move at least one of terminal plate  54  and output plate  56  relative to the other, to align the chosen fiber-optic lead  24  with proximal lens  28 . In some embodiments, optical oil may be employed between the interface of terminal plate  54  and output plate  56  and/or proximal lens  28  in order to aid in the transmission of the optical data from fiber-optic leads  24  to proximal lens  28 . 
     In one form, a mechanical actuator  64  is coupled to output plate  56 , and is operative to move output plate  56  relative to terminal plate  54  to align proximal lens  28  with the output of a chosen fiber optic lead  24  via output port  62 . In one form, the movement is via remote control of actuator  64  in response to commands from controller  34 , e.g., via human input to a keyboard  66  coupled to controller  34 . In other embodiments, the movement may be by hand. In still other embodiments, fiber channel selection switch  26  may be operative to move output plate  56  relative to terminal plate  54  in order to align the output of a fiber-optic lead  24  with proximal lens  28 , or to move terminal plate  54  in addition to or in place of moving output plate  56  to effect the alignment. In one form, the movement is translational. In various embodiments, the movement may be translational and/or rotational, e.g., depending on the geometries of terminal plate  54  and output plate  56 . It will be understood that the term “plate” in “terminal plate  54 ” and “output plate  56 ” is descriptive only, and that the physical geometry of those components may be any suitable geometry that allows the transmission of optical data from a selected one or more fiber-optic lead  24  to proximal lens  28 . 
     Optical filter  30  is operative to filter the raw optical image data prior to it reaching detector  32 . In one form, optical filter  30  is a band-pass filter. In other embodiments, other filter types may be employed, e.g., high pass filters, low pass filters, or multiple band-pass filters. In a particular form, optical filter  30  is operative to restrict the raw optical image data to a range of approximately 0.9 to approximately 1.05 micron wavelength, which restricts system  20  to collecting NIR data to the range of 0.9 to 1.05 microns. In other embodiments, optical filter  30  may be configured to pass other wavelengths in addition to or in place of 0.9 to 1.05 microns, e.g., depending upon the temperatures exhibited by structure  10  and fluid  14 . 
     In the depicted embodiment, optical filter  30  is positioned between proximal lens  28  and detector  32 . In other embodiments, optical filter  30  may be positioned in other locations. Alternate locations for optical filter  30  include, but are not limited to, being positioned inside or on one more optical collection elements  22 , at the proximal end  60  or distal end  44  of one or more fiber-optic leads  24 , or between proximal lens  28  and terminal plate  54  of fiber channel selection switch  26 . 
     Proximal lens  28  is operative to focus the raw optical data onto detector  32 . In one form, system  20  employs a single proximal lens  28 . In other embodiments, more than one proximal lens may be employed. Detector  32  is an optical head. In one form, detector  32  is operative to convert the raw optical data into electrical signals. In one form, detector  32  is a digital device. In other embodiments, detector  32  may be an analog device. In a particular form, detector  32  is digital camera. In other embodiments, an analog camera may be employed. In a more particular form, detector  32  is an indium-gallium-arsenide detector. One commercially available device that is suitable for use as detector  32  is the Alpha NIR™ camera available from FLIR Systems, Inc. 
     Controller  34  is communicatively coupled to detector  32 , display  36 , actuator  64  and keyboard  66  via communications links  68 ,  70 ,  72  and  74 . In one form, communications links  68 ,  70 ,  72  and  74  are wired connections. In other embodiments, wireless connections or combinations of wired and wireless connections may be employed. Although display  36  is coupled to controller  34  in the present embodiment, in other embodiments, display  36  may be coupled directly to detector  32 . 
     Controller  34  is configured to execute program instructions to, among other things, receive the output of detector  32 , display the output on display  36 , and store the output in a suitable memory device. Controller  34  is also operative to control actuator  64  to align proximal lens  28  with the selected fiber-optic lead  24 . The alignment may be performed automatically by controller  34  and/or manually by operator input via keyboard  66 . 
     In one form, controller  34  is microprocessor based and the program instructions are in the form of software stored in a memory (not shown). In a particular form, controller  34  is a computer having a data acquisition card in communication with detector  32 . However, it is alternatively contemplated that the controller and program instructions may be in the form of any combination of software, firmware and hardware, including state machines, and may reflect the output of discreet devices and/or integrated circuits, which may be co-located at a particular location or distributed across more than one location, including any digital and/or analog devices configured to achieve the same or similar results as a processor-based controller executing software or firmware based instructions. 
     During operation, system  20  is operative to selectively view different areas of interest inside structure  12 , e.g., areas of interest in or on structure  10  and fluid  14  by aligning the output of a fiber-optic lead  24  associated with the desired area of interest with proximal lens  28 . This alignment completes the optical path from the area of interest to detector  32  via the optical collection element  22 , fiber-optic lead  24 , proximal lens  28  and optical filter  30 . The data output by detector  32  in response to detecting the optical data from optical collection elements  22  may be displayed in display  36 , and may also be analyzed to determine temperature data associated with structure  10  and fluid  14 . 
     Embodiments of the present invention include a system for measuring radiant energy from a high temperature structure, comprising: a plurality of optical collection elements, wherein each optical collection element is operative to view an area of interest; a plurality of fiber-optic leads in optical communication with the plurality of optical collection elements; a fiber channel selection switch having an image output port and being structured to receive the plurality of fiber-optic leads; a proximal lens in optical communication with the image output port; and a detector in optical communication with the proximal lens and operative to capture optical data from the proximal lens, wherein the fiber channel selection switch is structured to selectively expose the output port to a chosen fiber-optic lead in response to a control input. 
     In a refinement, control input is based on a human selection of a fiber-optic lead of the plurality of fiber-optic leads. 
     In another refinement, the fiber channel selection switch is remotely controlled. 
     In yet another refinement, each optical collection element includes a distal lens structured to view the area of interest. 
     In still another refinement, the distal lens is a reflecting prism. 
     In yet still another refinement, the reflecting prism includes a high temperature reflective coating configured for operation at temperatures of at least 1100° F. 
     In a further refinement, the fiber channel selection switch includes a terminal plate having individual terminals for mechanically coupling each fiber optic lead to the fiber channel selection switch; and wherein the fiber channel selection switch is structured to move at least one of the terminal plate and the output port relative to the other of the terminal plate and the output port to align the chosen fiber-optic lead with the output port. 
     In a yet further refinement, a fiber-optic lead of the plurality of fiber-optic leads is a fused silica optical-fiber bundle. 
     In a yet still further refinement, the system includes an optical filter positioned to filter the optical data prior to capture of the optical data by the detector. 
     In an additional refinement, the optical filter is a band-pass filter operative to pass near-infrared radiation having wavelengths in the range of 0.9 to 1.05 microns. 
     Embodiments of the present invention include a system for measuring radiant energy in a gas turbine engine component, comprising: a plurality of optical collection elements, wherein each optical collection element is positioned inside one of a gas turbine engine and a gas turbine engine test rig, and wherein each optical collection element is operative to view an area of interest on the gas turbine engine component; a plurality of fiber-optic leads in optical communication with the plurality of optical collection elements and extending to outside of the one of the gas turbine engine and the gas turbine engine test rig; and means for selectively capturing optical data from a chosen fiber-optic lead, wherein the means for selectively capturing the optical data are positioned outside of the one of the gas turbine engine and the gas turbine engine test rig. 
     In a refinement, the means for selectively capturing optical data includes a proximal lens selectively exposed to the chosen fiber-optic lead to complete an optical path between the chosen fiber-optic lead and the proximal lens. 
     In another refinement, the means for selectively capturing optical data includes a near-infrared (NIR) detector. 
     In yet another refinement, the NIR detector is a camera. 
     In still another refinement, the NIR detector is a digital device. 
     In yet still another refinement, the NIR detector is an indium-gallium-arsenide detector. 
     In a further refinement, at least one of the fiber-optic leads and at least one of the optical collection elements are uncooled and are configured for operation in temperatures of at least 1100° F. 
     In a yet further refinement, at least one of the fiber-optic leads and at least one of the optical collection elements are uncooled and are configured for operation in temperatures of up to 2100° F. 
     Embodiments of the present invention include a method for measuring radiant energy, comprising: coupling first ends of a plurality of fiber-optic leads with a plurality of optical collection elements; positioning the optical collection elements in a high temperature apparatus, wherein each optical collection element is operative to view an area of interest; coupling second ends of the plurality of fiber-optic leads to a fiber channel selection switch having a plurality of terminals configured to receive the second ends; positioning a proximal lens in optical communication with an output port of the fiber channel selection switch; choosing a fiber-optic lead for viewing; exposing the output port to the chosen fiber-optic lead; and capturing optical data from the chosen fiber-optic lead via the proximal lens. 
     In a refinement, the exposing of the output port to the chosen fiber-optic lead includes moving at least one of the proximal lens and a terminal of the plurality of terminals associated with the chosen fiber-optic lead relative to the other to optically align the chosen fiber-optic lead with the proximal lens. 
     While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment(s), but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as permitted under the law. Furthermore it should be understood that while the use of the word preferable, preferably, or preferred in the description above indicates that feature so described may be more desirable, it nonetheless may not be necessary and any embodiment lacking the same may be contemplated as within the scope of the invention, that scope being defined by the claims that follow. In reading the claims it is intended that when words such as “a,” “an,” “at least one” and “at least a portion” are used, there is no intention to limit the claim to only one item unless specifically stated to the contrary in the claim. Further, when the language “at least a portion” and/or “a portion” is used the item may include a portion and/or the entire item unless specifically stated to the contrary.