Patent ID: 12253002

It is noted that the drawings of the disclosure are not to scale. The drawings are intended to depict only typical aspects of the disclosure, and therefore should not be considered as limiting the scope of the disclosure. In the drawings, like numbering represents like elements between the drawings.

DETAILED DESCRIPTION

As an initial matter, in order to clearly describe the current disclosure, it will become necessary to select certain terminology when referring to and describing relevant machine components within the illustrative application of a turbomachine. When doing this, if possible, common industry terminology will be used and employed in a manner consistent with its accepted meaning. Unless otherwise stated, such terminology should be given a broad interpretation consistent with the context of the present application and the scope of the appended claims. Those of ordinary skill in the art will appreciate that often a particular component may be referred to using several different or overlapping terms. What may be described herein as being a single part may include and be referenced in another context as consisting of multiple components. Alternatively, what may be described herein as including multiple components may be referred to elsewhere as a single part.

In addition, several descriptive terms may be used regularly herein, and it should prove helpful to define these terms at the onset of this section. These terms and their definitions, unless stated otherwise, are as follows. As used herein, “downstream” and “upstream” are terms that indicate a direction relative to the flow of a fluid, such as the working fluid through the turbomachine or, for example, the flow of air through the combustor or coolant through one of the turbomachine's component systems. The term “downstream” corresponds to the direction of flow of the fluid, and the term “upstream” refers to the direction opposite to the flow. The terms “forward” and “aft,” without any further specificity, refer to directions, with “forward” referring to the front or compressor end of the turbomachine, and “aft” referring to the rearward or turbine end of the engine.

It is often required to describe parts that are at different radial positions with regard to a center axis. The term “axial” refers to movement or position parallel to an axis, e.g., an axis of a turbomachine. The term “radial” refers to movement or position perpendicular to an axis, e.g., an axis of a turbomachine. In cases such as this, if a first component resides closer to the axis than a second component, it will be stated herein that the first component is “radially inward” or “inboard” of the second component. If, on the other hand, the first component resides further from the axis than the second component, it may be stated herein that the first component is “radially outward” or “outboard” of the second component. Finally, the term “circumferential” refers to movement or position around an axis, e.g., a circumferential interior surface of a casing extending about an axis of a turbomachine. As indicated above, it will be appreciated that such terms may be applied in relation to the axis of the turbomachine.

In addition, several descriptive terms may be used regularly herein, as described below. The terms “first”, “second”, and “third” may be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. “Optional” or “optionally” means that the subsequently described event may or may not occur or that the subsequently described feature may or may not be present and that the description includes instances where the event occurs or the feature is present and instances where the event does not occur or the feature is not present.

Where an element or layer is referred to as being “on,” “engaged to,” “disengaged from,” “connected to” or “coupled to” or “mounted to” another element or layer, it may be directly on, engaged, connected or coupled to the other element or layer, or intervening elements or layers may be present. In contrast, when an element is referred to as being “directly on,” “directly engaged to,” “directly connected to” or “directly coupled to” another element or layer, there are no intervening elements or layers present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.). As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. The verb forms of “couple” and “mount” may be used interchangeably herein.

I. General Introduction

The disclosure provides various embodiments of methods, systems and ancillary structures and tools for enabling use of sensor(s) within a circumferential interior surface of at least part of a turbomachine casing (e.g., a circumferential portion of the circumferential interior surface). In one embodiment, a sensor or an array of sensors may be positioned on the circumferential interior surface of the casing with the communication leads from the sensor(s) being routed in the circumferential direction to one or more exit openings that act as points of egress. The sensors and their communication leads may be at least partially embedded in the casing, possibly utilizing a mounting member (e.g., a track, housing, or carrier), which fits within a slot machined in the circumferential interior surface, i.e., the inner diameter, of the casing in the circumferential direction. The sensor(s) may alternatively be surface-mounted to the circumferential interior surface of the casing using adhesive, straps, or other means of securing. The sensors may provide discrete or continuous measurement points.

Embodiments of the disclosure provide sensor(s) positioned on a circumferential interior surface of a casing without machining radial penetrations and that provide a number of advantages over conventional radially mounted sensors. The sensor(s) can be located at the measurement point of interest and the associated communication leads can be routed in the circumferential direction. The communication leads for the sensor(s) at a given turbomachine stage may be grouped and routed to a common point of egress through the casing, and to their respective data acquisition systems. This minimizes the number of penetrations through the wall of the casing. For blade tip timing and blade tip clearance measurements, both of which are non-contact sensor systems, sensor(s) may be installed on the circumferential interior surface of the casing in the plane of the rotating blades.

In alternative embodiments of the disclosure, a circumferentially routed device may not have sensing capability, but may provide ancillary functions, such as an antenna, tube, wire, optical fiber, or other supporting elements. Other embodiments of the disclosure provide an optical sensor capable of use on the circumferential interior surface of the casing, and a tool for forming, among other things, a circumferentially extending slot on the circumferential interior surface of the casing. In particular embodiments, the circumferentially extending slot may extend only partially circumferentially around the circumferential interior surface of the casing.

II. Introduction to Turbomachine and Casing

FIG.1is a cross-sectional illustration of an industrial machine90in the form of a turbomachine100. In this example, turbomachine100is in the form of a combustion or gas turbine system. Turbomachine100includes a compressor102and a combustion region104. Combustion region104includes a combustor106and a fuel nozzle assembly108. Turbomachine100also includes a turbine assembly110and a common compressor/turbine rotor112(sometimes referred to as a shaft).

In one embodiment, the combustion turbine system is a MS7001FB engine, sometimes referred to as a 7FB engine, commercially available from General Electric Company, Greenville, S.C. The present disclosure is not limited to any one particular industrial machine, nor is it limited to any particular combustion turbine system and may be implanted in connection with other engines including, for example, the MS7001FA (7FA), the MS9001FA (9FA), the 7HA and the 9HA engine models of General Electric Company. Furthermore, the present disclosure is not limited to any particular turbomachine and may be applicable to, for example, steam turbines, jet engines, compressors, turbofans, etc.

In operation, air flows through compressor102, and compressed air is supplied to combustion region104. Specifically, the compressed air is supplied to fuel nozzle assembly108that is integral to combustion region104. Assembly108is in flow communication with combustion region104. Fuel nozzle assembly108is also in flow communication with a fuel source (not shown inFIG.1) and channels fuel and air to combustion region104. Combustors106in combustion region104ignite and combust fuel. Combustors106are in flow communication with turbine assembly110within which gas stream thermal energy is converted to mechanical rotational energy. Turbine assembly110includes a turbine (e.g., an expansion turbine) that rotatably couples to and drives rotor112. Compressor102also is rotatably coupled to rotor112. In the illustrative embodiment, there is a plurality of combustors106and fuel nozzle assemblies108.

FIG.2shows a cross-sectional view of an enlarged portion of an illustrative compressor102of turbomachine100(FIG.1).FIG.2is of a lower cross-section of compressor102, with rotor112above a stationary casing122. Compressor102includes stages120of (stationary) nozzles or vanes126(two shown) coupled to stationary casing122of turbomachine100and axially adjacent a stage124of rotating blades132. Casing122extends about nozzles126and rotating blades132and forms a flow path for a working fluid (not shown). Numerous circumferentially spaced nozzles or vanes126may each be held in compressor102by a radially outer platform128in mounts164positioned in casing122. Each stage124of rotating blades132in compressor102includes numerous circumferentially spaced rotating blades132coupled to rotor112and rotating with the rotor. Rotating blades132may include a radially inward platform134(at root of blade) coupled to rotor112. While the teachings of the disclosure will be described relative to compressor102, it is understood that the disclosure may be applied to other industrial machines including rotating parts and other turbomachine parts, e.g., turbine assembly110.

FIG.3shows a cross-sectional view of a casing122. In a method according to embodiments of the disclosure, casing122includes a casing body144having a first (upper) portion142and a second (lower) portion146.FIG.3shows first portion142of casing122of turbomachine100(FIG.1) being removed from second portion146. First portion142may be removed by removing any necessary ancillary casing equipment (not shown) that extends about first portion142(e.g., pipes, insulation, flanges, lifting lugs, other instrumentation, bolts, or any other physical object in close proximity to the casing), unbolting first portion142from second portion146, and lifting first portion142away from second portion146. Embodiments of the disclosure can be advantageously carried out with first portion142on-site on a floor in a power plant or in a manufacturing site.

Casing body144and each portion142,146include a circumferential interior surface152and an exterior surface154. Portions142,146can take any shape and circumferential extent of casing body144. In many cases, each portion142,146take the form a half-shell casing148,150, e.g., 180° of a circular casing body144, that can mount together via mating flanges156thereof (fasteners not shown). In this case, first portion142includes an upper half-shell casing148, and second portion146includes a lower half-shell casing150. In the field of use of turbomachine100(FIG.1), where first portion142is removed, rotor112(in phantom inFIG.3) may remain in second portion146. Here, sensor systems according to embodiments of the disclosure may be applied to first portion142, alone. Alternatively, in certain embodiments, rotor112may be removed so sensor systems according to the disclosure can be applied to second portion146alone, or to both first and second portion142,146.

III. Sensor System on Circumferential Interior Surface of Casing and Related Method

FIGS.4and5show an illustrative half-shell casing, e.g.,148, removed from turbomachine100(FIG.1) and including a sensor system160according to one embodiment of the disclosure.FIG.4shows a single sensor system160, andFIG.5shows a number of axially spaced sensor systems160. As observed inFIGS.2,4and5, circumferential interior surface152may take a variety of forms depending on, for example, the type of nozzles126(FIG.2) employed, the stage of compressor102or turbine assembly110, and the type and/or size of turbomachine100. Generally, circumferential interior surface152may include any portion of an inner surface or inner diameter of casing body144that extends in a circumferential manner, i.e., at least partially around an axis A of turbomachine100(FIG.1). “Circumferential interior surface152” may be referred to herein as “interior surface152” or “surface152” for brevity. The phrase “only a circumferential portion” of the circumferential interior surface refers to a feature (e.g., a slot or mounting member) that has a circumferential length less than the circumferential length of the circumferential interior surface in which the feature is formed or installed.

Sensor system(s)160may be mounted in any space162, for example, between mounts164for a pair of stages120of nozzles126, in interior surface152of casing body144. The form of mounts164may vary. InFIGS.2and4, and the upper portion ofFIG.5, mounts164include a track166in which nozzles126may be circumferentially inserted (nozzles removed inFIGS.4and5). In other embodiments, as shown in the lower portion ofFIG.5, mounts164may include circular openings168into which variable vanes/nozzles (not shown) are positioned. (SeeFIG.41for description of how the circular opening168alternative is handled.) In any event, space162extends at least partially about interior surface152.

FIGS.2and6-8show cross-sectional views of sensor systems160according to various embodiments of the disclosure. Regardless of embodiment, sensor system160includes at least one sensor170coupled relative to interior surface152of casing body144. Sensor(s)170extends at most only partially through casing body144. That is, sensor(s)170extend from interior surface152radially outward, but do not penetrate through to exterior surface154of casing122. As will be described in greater detail herein, and as shown best inFIG.5, sensor system160may include sets of sensors170, e.g., a first set of sensor(s)170A and one or more second sets of sensors170B, coupled relative to interior surface152of casing body144. Again, sensors170only extend at most partially through casing body144. Since each sensor170extends at most partially through casing body144, the disadvantages of radially extending sensors described herein are avoided.

A method according to embodiments of the disclosure may include coupling sensor(s)170relative to interior surface152of first portion142(FIGS.3-5) of casing body144. That is, sensor(s)170may be coupled to first portion142alone, after removal from turbomachine100(FIG.1). In addition, or as an alternative, the method may include coupling sensor(s)170relative to interior surface152of second portion146(FIG.3) of casing body144, i.e., after removal of rotor112(FIG.3). In any event, sensor(s)170at most only partially extend through casing body144.

As will be described herein in greater detail, each sensor170includes a communications lead174operatively coupled thereto. Communication lead(s)174for sensor(s)170may be routed to extend circumferentially along interior surface152of casing body144of casing122. Advantageously, with casing122in a completed, operative state, i.e., with half-shell casings148,150together, any number of communication lead(s)174used can exit casing122at a single exit opening186(FIG.9). In an alternative embodiment, more than one exit opening186(FIG.9) is provided, but in any event, the number of exit openings is greatly reduced compared to conventional radially extending sensors.

A. Sensor System Mounting

Sensor systems160may be mounted to an axially extending space162of interior surface152, e.g., between mounts164for a pair of adjacent stages120of nozzles126, in a variety of ways. Embodiments of the disclosure provide for coupling sensor(s)170relative to interior surface152of at least one of first and second portions142,146of casing body144of casing122. Again, each sensor170at most extends in the radial direction only partially through casing body144.

1. Adhering Sensor System

Coupling sensor(s)170may include adhering the sensor(s) to interior surface152of first portion142and/or second portion146of casing body144. Sensor(s)170may be adhered in a number of ways.FIG.6shows a cross-sectional view of a sensor system160in which sensor(s)170is/are coupled relative to interior surface152of casing body144by an adhesive element172. That is, sensor(s)170is/are coupled relative to interior surface152of casing body144in space162between mounts164for pair of stages120(FIG.2) of nozzles by adhesive element172. Adhesive element172may also adhere communication leads174along interior surface152. Adhesive element172may be provided with openings, as necessary, to expose sensors170. Adhesive element172may include any form of adhesive capable of withstanding the environment in which employed, e.g., a glue, a polymer, tape, etc. In another embodiment, sensors170could be fixedly coupled to interior surface152, e.g., using Nichrome strips spotted welded to the casing.

2. Partially Embedding Sensor System

Coupling sensor(s)170may include at least partially embedding them in interior surface152.FIG.7shows a cross-sectional view of sensor system160in which sensor(s)170is/are at least partially embedded in interior surface152of casing body144in space162, e.g., between mounts164for pair of stages120(FIG.2) of nozzles (not shown). Each sensor170may be positioned in a respective individual slot176, or a plurality of sensors170may be positioned in a continuous slot176. Slot(s)176may have any shape configured to receive one or more sensors170. In the example shown, slot(s)176is mostly circular, and sensor(s)170and/or communication leads174are configured to fit within slot(s)176. A protective cover178may be employed to protect sensor(s)170in this setting with any necessary openings required to expose sensor(s)170provided therein. Protective cover178may include, for example, a Nichrome strip.

3. Mounting Sensor System with Mounting Member

FIGS.2,4,5,8and10-26show details of an embodiment of the disclosure in which sensor(s)170may be mounted in a mounting member or track that is mounted to circumferential interior surface152of casing body144.FIGS.4and5show perspective views of mounting member(s)180in casing body144of casing122, andFIG.8shows a cross-sectional view of sensor system160in which a mounting member or track180is provided.FIG.4shows one circumferential arrangement of mounting member(s)180, andFIG.5shows numerous axially spaced, circumferential arrangements of mounting member(s)180, i.e., numerous sensor systems160within the same circumferential interior surface152. In this embodiment, mounting member180is configured to be mounted relative to circumferential interior surface152of casing body144in space162between mounts164for pair of stages120(FIG.2) of nozzles. Coupling sensor(s)170according to this embodiment may include mounting the mounting member180in a slot182in interior surface152of the at least one of first and/or second portions142,146of casing body144. Slot182may be a discrete, planar slot as shown in a lower end ofFIG.4, or as shown in an upper end ofFIG.4and inFIG.5, slot182may be an elongated and at least partially circumferentially extending slot. In either case, mounting member180may be positioned in slot182(i.e., a discrete, planar slot or in at least partially circumferentially extending slot182) in space162in interior surface152between the mounts for the pair of the plurality of stages of nozzles.

Methods according to embodiments of the disclosure may include forming slot(s)182prior to coupling of sensor(s)170therein using mounting member(s)180. Pair of stages120(FIG.2) of nozzles126may be removed prior to forming slot182in interior surface152of casing body144. Slot182may be formed using any now known or later developed technique, e.g., machining. In one embodiment, where slot182includes an at least partially circumferentially extending slot in space162in circumferential interior surface152, the slot may be formed using a tool and method as described in Section IV herein. In any event, slot182extends at most only partially through casing body144, i.e., it extends only partially (radially) between circumferential interior surface152and exterior surface154of casing body144and does not extend through exterior surface154of casing body144. Consequently, sensor system160will not extend through casing body144, in contrast to conventional radially extending sensor systems.

Referring toFIGS.10-26, details of mounting member180for sensor(s)170for turbomachine100(FIG.1) according to various embodiments will now be described.FIG.10shows a perspective view of mounting member180in slot182with stage120of rotating blades132;FIG.11shows a side and top perspective view of mounting member180including axially spaced sensor(s)170apart from a slot;FIG.12shows a side and top perspective view of mounting member180including a single row of sensor(s)170; andFIG.13shows a side and bottom perspective view of mounting member180ofFIG.12, according to one embodiment.

In this mounting embodiment, sensor system160may include mounting member180including a body210configured to be mounted to circumferential interior surface152of at least a portion of casing122of turbomachine100(FIG.1). Sensor(s)170is/are coupled to mounting member180and configured to measure an operational parameter of the turbomachine. Where body210will extend along a portion of circumferential interior surface152of casing122that is sufficiently elongated to require curvature of body210(e.g., for ease of mounting and/or to prevent excessive penetration into casing body144), body210may have a radius of curvature R substantially matching the circumferential portion of circumferential interior surface152of casing122of turbomachine100(FIG.1).

More particularly, body210of first mounting member180may include an arcuate portion212having a radius of curvature R substantially matching, i.e., the same or nearly the same as, a radius of curvature R of circumferential interior surface152. The length of arcuate portion212, i.e., the degrees of curvature over which it extends, may vary. For example, arcuate portion(s)212could extend over only a circumferential portion of circumferential interior surface152of casing122of 5°, 10°, 20°, 30°, 45°, 90°, or any value up to the degrees of curvature of first or second portion142,146of casing122to which it is to be mounted. As shown inFIGS.4and5, where portions142,146represent half-shell casings148,150(FIG.3), a single arcuate portion212therefor may extend 180° degrees. In some embodiments, as shown best in the perspective view ofFIG.14, body210of mounting member180may include a plurality of arcuate portions212having radius of curvature R substantially matching the circumferential portion of circumferential interior surface152of casing122of turbomachine100(FIG.1).

As will be described in greater detail, each arcuate portion212is mounted in slot182to collectively provide sensor(s)170along a desired circumferential extent of circumferential interior surface152. Any number of arcuate portions212may be employed to cover the desired circumferential extent of slot182. For example, as noted, mounting member180may include a single arcuate portion212that covers up to 180° of a 180° slot182. Alternatively, five arcuate portions may cover 9° each of a 45° slot182; ten arcuate portions212may cover 18° each of a 180° slot182; one arcuate portion may cover 10° of a 10° slot182(see e.g., lower portion ofFIG.4); or four arcuate portions212may cover 15° of a 90° slot182, etc. For example, circumferential portion may extend no more than 10° along the circumferential interior surface152. Where a plurality of sensors170are used, they may be spaced at any desired spacing. Where sensor(s)170are not desired but a slot182exists, ‘dummy’ arcuate portions with no sensors therein and no openings220therein may be employed to fill the slot, provide a continuous passage240for communications link174, and provide a continuous circumferential interior surface for casing122. In one embodiment, mounting member(s)180may be circumferentially fixed using set screws (not shown) extending through openings226therein into the casing.

Referring toFIGS.12,15and16, mounting member180may also include an opening220extending through a radially inner surface222of body210. Each opening220may be configured to position a respective sensor170(or part thereof) facing radially inward relative to axis A (FIG.12only). Hence, a plurality of openings220may extend through radially inner surface222of body210with each opening220configured to position a sensor170of a plurality of sensors (see e.g.,FIGS.4-12,15and16) such that each sensor faces in a radially inward relative to the axis, i.e., an operative direction for the sensor at or nearly radially inward relative to the axis. Opening220may provide an active part of mounting and/or positioning a respective sensor170, or it may just allow sensor170to be exposed radially inward. In the examples inFIGS.12,15and16, sensor170includes a sensor head224configured to seat in opening220(e.g., circular sensor head in circular opening); however, this is not necessary in all instances.

In one embodiment, such as shown inFIG.12, opening(s)220for a single type of sensor170is provided, e.g., tip timing laser probe or clearance probe. Alternatively, as shown inFIG.15, more than one type of opening220may be provided in each mounting member180, e.g., a single opening220A for sensor(s)170requiring only one opening like a proximity sensor or, for example, two axially spaced openings220B for a time-of-arrival optical sensor that includes a sender and a receiver (not shown, see e.g.,FIG.27-30). Axially spaced openings220B may also position different types of sensors. For example, in theFIG.15embodiment, opening220A can position a sensor170A such as a capacitive sensor, one of openings220B can position a single tip timing probe170B including a pair of optical fibers (one for send and one for receive, see e.g.,FIG.31), and a second of openings220B can position, axially offset from timing probe170B, a completely independent laser probe170C with its own send and receive optical fibers. (While the send and receive optical fibers may be in extremely close proximity, it is conceivable that the send optical fiber and the receive optical fiber could be separated, each having their own opening220interfacing with the flow path.)

Any number of openings220can be provided for a single type of sensor, or for a number of different sensors. Mounting member180can be made wider to accommodate any number of axially spaced openings/sensors. Where more axially spaced sensors are desired, more than one sensor system160can be employed in an axially spaced arrangement. Openings220may have any radially inward facing structure desired to assist in directing signals from sensor(s)170or protecting the sensors. For example, as shown inFIG.11, a radially inner portion234of opening220may be beveled, rounded, angled, etc. Other radially inward facing structures, such as protective covers, are also possible.

Mounting member180may include any now known or later developed mechanism for holding sensor(s)170in place. InFIGS.12and15, sensor(s)170may be held in place, for example, by threaded fasteners in openings226extending through radially inner surface222of body210.FIG.16shows a perspective view of sensor170including complementary threaded fastener receptacles228. As also shown inFIG.16, each sensor170may include a communications lead174operatively coupled thereto, or each sensor170may share a communications lead174with other sensors170. While a particular mechanism to position sensor(s)170has been described, a wide variety of alternative mechanisms may be employed. For example, as shown inFIG.13, sensor(s)170may be snap-fit into seats230, e.g., with flexible wedges, in body210. In this setting, openings226for attaching sensor(s)170may be omitted. Sensor(s)170can also be connected by any other form of fastener, adhesive, complementary male-female connections, etc.

As shown inFIGS.12and13, mounting member180also includes a passage240in body210. Passage240may extend longitudinally through body210to allow routing of communications lead(s)174of sensor(s)170circumferentially relative to the circumferential interior surface152(e.g.,FIGS.10,14) of casing122and within slot182. In this manner, a communications lead174can be operatively coupled to each sensor170, and passage240may be used to route the communications leads174in a circumferential direction of casing122, protecting the leads from the environment inside the casing. Passage240may also provide space for sensor(s)170therein. Passage240may have any desired cross-sectional shape, e.g., square, rectangular, semi-circular, etc., and may have any size required to, for example, position sensor(s)170and/or route communications lead(s)174. In one embodiment, as shown in the side and bottom perspective view ofFIG.17, mounting member180may include a cover246that encloses passage240. Cover246may be coupled to body210in any known fashion, e.g., threaded fasteners, welding, male-female connectors, etc. Cover246can be made of the same material as body210.

As noted, coupling mounting member180to circumferential interior surface152may include mounting arcuate portion(s)212in at least partially circumferentially extending slot182in circumferential interior surface152, e.g., by circumferentially inserting one or more arcuate portions212into slot182. Mounting member180and body210thereof may take a variety of forms to implement the mounting.FIG.18shows a cross-sectional view of an illustrative mounting member180and a slot182in circumferential interior surface152in space162between pair of mounts164. In one embodiment, illustratively shown inFIG.18, body210may have a cross-section configured to mate with a complementary cross-section of at least partially circumferentially extending slot182in circumferential interior surface152of casing122, creating complementary cross-sections. Where body210is sized to extend along a circumferential portion of an only partially circumferentially extending slot182in circumferential interior surface152of casing122(see e.g., bottom ofFIG.4), body210may have a cross-section configured to mate with a complementary cross-section of the only partially circumferentially extending slot182. The cross-section of body210and the complementary cross-section of the only partially circumferentially extending slot182radially fixes body210relative to circumferential interior surface152. Again, the complementary cross-sections allow circumferential insertion of body210into the only partially circumferentially extending slot182.

As used herein, “complementary” does not necessary indicate a perfect size and shape match, but only that the cross-sections interact to provide a number of advantageous functions. First, the cross-section of body210and the complementary cross-section of slot182may interact to fix body210relative to circumferential interior surface152, e.g., radially and axially. For example, the complementary cross-sections may interact to prevent mounting member180from moving radially relative to circumferential interior surface152. Further, the complementary cross-sections may interact to fix mounting member180relative to circumferential interior surface152such that circumferential interior surface152of casing122and radially inner surface222of body210are substantially coplanar. In this manner, a flow F (FIG.18) of working fluid thereover is not interrupted by mounting member180.

Body210and any arcuate portions212thereof may be fixed circumferentially in a variety of manners. For example, as noted, mounting member180may extend 180°, either as a single arcuate portion212or with many arcuate portions212, about a half-shell casing148,150(FIG.3) so ends248(FIG.18) of mounting member180abut a flange156(FIG.4) of the other half-shell casing to hold mounting member180circumferentially. In other examples, mounting members180may be welded in place, pegged or otherwise fastened in place, etc. Lastly, complementary cross-sections allow circumferential insertion of mounting member180, body210and/or arcuate portion(s)212thereof into at least partially circumferentially extending slot182. For example, as shown inFIG.4, where first or second portion142,146, respectively, are exposed, an end of slot182is open, e.g., at a flange156of casing body144, such that mounting member180, body210and/or arcuate portion(s)212thereof can be slid into place therein.

InFIG.18, body210has a cross-section that is generally rectangular (excepting where passage240exists) with axial extensions250, i.e., with extensions extending axially therefrom. Similarly, at least partially circumferentially extending slot182has a complementary cross-section that is rectangular with axial seats252configured to retain axial extensions250of body210. Axial extensions250and axial seats252are referred to as axial because they extend axially. It is noted that while extension/seat pairs are shown in a directly opposing arrangement relative to sides of body210, they do not have to be arranged in that manner. That is, the extension/seat pair on one side of body210can be in a radially different location than the extension/seat pair on the other side of body210—see e.g.,FIG.2. Slot182axially retains body210of mounting member180by interacting with axially facing sides254of body210. Extensions250and seats252are configured to radially fix mounting member180relative to circumferential interior surface152and make circumferential interior surface152of casing122and radially inner surface222of body210substantially coplanar. InFIG.18, axial extensions250and axial seats252have complementary polygonal cross-sections. In the cross-sectional view ofFIG.19, body210has axial extensions250and slot182has axial seats252, that have complementary rounded (e.g., hemispherical) cross-sections. (Note, variations of theFIG.18embodiment are also shown inFIGS.2,11-13and17).

FIG.20-23show cross-sections of a variety of alternative embodiments of complementary cross-sections of slot182and body210. The various embodiments provide similar function as that ofFIGS.18and19.FIG.20shows an arrangement in which body210has a T-shaped cross-section260, and at least partially circumferentially extending slot182has a complementary T-shaped cross-section262configured to receive the T-shaped cross-section of the body. (Note,FIG.20shows the T-shaped cross-sections inverted due to the location of the cross-section). Here, the top of the T-shape is internal to body210, preventing radial removal of body210.FIG.21shows an arrangement in which body210has a T-shaped cross-section extension264, and at least partially circumferentially extending slot182has a complementary T-shaped cross-section extension266configured to receive the T-shaped cross-section extension264of the body210.FIG.22shows an arrangement in which body210has a dovetail cross-section268, and at least partially circumferentially extending slot182has a complementary dovetail cross-section270configured to receive the dovetail cross-section of the body. The dovetail cross-sections are arranged to prevent radial removal of body210.FIG.23shows an arrangement in which body210has an at least partially circular cross-section272, and the at least partially circumferentially extending slot182has a complementary at least partially circular cross-section274configured to receive the at least partially circular cross-section of the body. The partially circular cross-sections are arranged to prevent radial removal of body210.

FIGS.24-26show cross-sections of a variety of alternative embodiments of complementary cross-sections of slot182and body210. In addition, a variety of additional mounting structures that can be used as illustrated, or with any of the embodiments described herein, are also shown.FIGS.24and25show a cross-section in which body210and slot182are rectangular. In addition,FIGS.24and25show a threaded fastener258coupling mounting member180to circumferential interior surface152and, in particular, to slot182. InFIG.24, threaded fastener258extends from radially inner surface222of body210of mounting member180into casing122, within slot182. InFIG.25, threaded fastener258extends from exterior surface154of casing122, into slot182and into body210of mounting member180.FIG.25necessitates an additional exterior opening(s) in casing122. Any number of threaded fasteners258may be employed per mounting member180. While particular locations for threaded fasteners258are illustrated, they can be located in any desired location capable of fixing mounting member180to casing122. Mounting member180can include any necessary structures to receive threaded fastener258, e.g., bosses, threaded openings, etc.FIG.8shows a complementary rectangular cross-section without fasteners.FIG.26shows a cross-section in which body210and slot182are T-shaped with the top of the T-shape at radially inner surface222of body. Here, body210is held to slot182by, for example, welds276. Welds could be applied to theFIG.8embodiment also.

Referring again toFIG.2, certain spaces162of circumferential interior surface152may be non-parallel with axis A of turbomachine100(FIG.1). For example, circumferential interior surface152may be angled at a non-parallel angle α relative to axis A to direct a working fluid, e.g., air or combustion gases, in a desired manner. While body210has been shown in most of the drawings as being generally rectangular in cross-section (except for passage240and extensions250), as shown inFIG.2, body210can also have a cross-section configured to ensure circumferential interior surface152of casing122and radially inner surface222of body210are substantially coplanar, even where circumferential interior surface152is not parallel with axis A and/or a bottom surface of slot182is not parallel with circumferential interior surface152. Here, radially inner surface222of body210of mounting member180may be angled to match that of circumferential interior surface152. For example, radially inner surface222of body210may be non-parallel with radially outer surface280of body210of mounting member180. Body210may thus have a non-uniform radial height (up/down page inFIG.2).

Mounting member(s)180and exposed portions of sensor(s)170may be made out of any material capable of withstanding the environment of the component of turbomachine100(FIG.1) in which employed. In one example, mounting members180and exposed portions of sensor(s)170may be made out of 410 stainless steel, or any of a variety of metals capable of use in turbomachine100(FIG.1) and usable in an additive manufacturing setting such as but not limited to direct metal laser melting (DMLM). The materials used may be selected to match the coefficient of thermal expansion (CTE) of the material of circumferential interior surface152and casing body144, e.g., to keep mounting member(s)180from expanding or contracting at a different rate, thereby causing it to buckle or causing a gap to open.

B. Additional Sensor Systems

A number of sensor systems160may be employed in a single casing122, according to embodiments of the disclosure. A casing122for turbomachine100(FIG.1) may thus include casing body144including circumferential interior surface152and exterior surface154, and a sensor system160, as described herein. Casing122can also include at least one additional sensor system160, as described herein, see e.g.,FIG.5, in which a set of three sensor systems160is used in one space162, and two sets of 2 sensor systems160are employed in another space162. Each additional sensor system160may be mounted in any manner described herein. For example, each additional sensor system160may include a mounting member180, as described herein, in a respective at least partially circumferentially extending slot182in space162in circumferential interior surface152between mounts164for pair of stages120(FIG.2) of nozzles126(FIG.2). Slots182for each system may be axially distanced from one another.

Referring toFIGS.2and5, each sensor system160may include a different set of sensors170coupled relative to circumferential interior surface152of casing body144, i.e., in space162between mounts164for pair of stages120(FIG.2) of nozzles. Accordingly, sensor(s)170in one sensor system160may be provided in addition to sensor(s)170in another sensor system160. Sensor(s)170in one sensor system160may being axially distant from sensor(s)170in another sensor system160, i.e., they are spaced relative to axis A of turbomachine100(FIG.1). Again, sensor(s)170extend at most only partially through casing body144in the radial direction.

Sensor(s)170may be coupled relative to interior surface152in any manner described herein relative toFIGS.6-8. In one example, shown inFIGS.2and5, each sensor system160may include its own mounting member180. As described, each mounting member(s)180includes sensor(s)170mounted therein. Each mounting member(s)180is configured to be mounted relative to interior surface152of casing body144in space162between mounts164for pair of stages120(FIG.2) of nozzles. Here, a number of at least partially circumferentially extending slots182is provided in space162. Each slot182is axially distanced from an adjacent slot182in interior surface152between mounts164. That is, each mounting member180may be positioned in a respective slot182such that sensor(s)170therein are axially distanced from sensor(s)170of an adjacent mounting member180, positioned in another slot182. Hence, sensors170can provide measurements at different axial locations within turbomachine100(FIG.1). For example, sensors170may provide rotating blade132(FIG.2) arrival time for fore and aft portions of rotating blades.

C. Communication Leads and Routing Thereof

As shown inFIGS.6-8,11, and16, each sensor170may include a communications lead174operatively coupled thereto for electrical or optical communication of its measurements, depending on type of sensor, to a data acquisition system (not shown) outside of casing body144. Alternatively, a number of sensors170may share a communications lead174. Communications lead174may include any signal communicating wire format, e.g., a fiber optic filament, metal or metal alloy wire (e.g., silver-plated copper wiring), etc., capable of carrying a signal. In contrast to conventional sensor systems, a method according to embodiments of the disclosure includes routing communications lead(s)174operatively coupled to sensor(s)170to extend circumferentially along interior surface152of casing body144. Hence, communications lead(s)174of sensor system160extend circumferentially along interior surface152of casing body144. Sensor(s)170and communications lead(s)174may be positioned in space162between mounts164for a pair of stages120(FIG.2) of nozzles in interior surface152of casing body144.

Referring toFIG.9, in contrast to conventional radially mounted sensors, communications leads174of sensors170may be routed circumferentially to exit casing body144at a single exit opening186. Communication leads174may also exit casing body144at a number of additional exit openings (not shown), but the number of exit openings is not one-to-one with the number of sensors170, and so the number of exit openings186can be drastically reduced as compared to the same number of conventional radially inserted sensors. That is, the number of exit openings in casing body144is reduced, and the number of communications leads174requiring routing on exterior surface154is simplified. Removal of equipment on exterior surface154of casing122is avoided.

A method according to embodiments of the disclosure may include routing communication lead(s)174relative to interior surface152of first portion142(FIGS.3-5) of casing body144. That is, communication lead(s)174may be routed on first portion142alone. In addition, or as an alternative, the method may include routing communication lead(s)174relative to interior surface152of second portion146(FIG.3) of casing body144, i.e., after removal of rotor112(FIG.3). In any event, communication lead(s)174extend circumferentially along interior surface152of casing body144, and not radially through or outwardly from casing body144.

D. Sensor Arrangements

As shown inFIGS.4-8, sensor(s)170may include a plurality of each sensor170coupled relative to interior surface152of casing body144in space162between mounts164for pair of stages120(FIG.2) of nozzles. Sensors170may be positioned anywhere necessary along circumferential interior surface152. For example, they may be positioned in a distributed manner (FIG.4) (e.g., circumferentially spaced, circumferentially equidistant, etc.), or as shown in the cross-sectional view ofFIG.9, in clusters at one or more discrete circumferential extents or portions of casing body144. For example, a cluster (plurality) of sensors170may be circumferentially spaced at no more than 5 degrees apart on body210.

As shown in the partial perspective view ofFIG.10, sensors170may be axially spaced within a given circumferential mounting arrangement. In the example shown inFIG.10, a number of sensors170are axially spaced within a single mounting member180. InFIG.15, sensors170may be singular and circumferentially spaced, and other sensors (to be located in openings220B) would be axially spaced and circumferentially spaced. Sensors170can also be axially spaced in any of the mounting scenarios shown inFIGS.6and7. In this manner and in contrast to radially positioned sensors, any number of sensors170of various types can be provided, and they can be spaced in close proximity without concern for mechanical integrity of casing body144. In one example, sensors170that measure blade timing for rotating blade132(FIG.2) leading and trailing edges and mid-core can be provided. Blade timing measurements of this type can typically be accomplished with conventional radially mounted sensors in different circumferential locations, requiring at least three openings in the casing and reducing the mechanical integrity of casing122.

Mounting members180may also include rake members (not shown) extending radially inward therefrom, where it is possible to provide them, e.g., at an axial end region of the casing. In this manner, sensors170can be positioned in any manner circumferentially, axially and radially.

E. Sensor Types

Sensors170may measure any now known or later developed operational parameter(s) of turbomachine100, including but not limited to: time of arrival for blade tip timing, blade tip clearance (post-outage), dynamic pressure, static pressure, rotating vibration, flow vibration, stall detection (e.g., using a compressor active stability management (CASM) sensor), rotor speed, optical rotor vibration, and/or temperature. Sensors170may take any now known or later developed form appropriate for measuring the operational parameters, e.g., optical, infrared, radio frequency, inductive, capacitive, etc. Where more than one sensor is provided, sensors170may measure the same operational parameter of turbomachine100(FIG.1), e.g., rotational blade proximity, or sensors170may measure different operational parameters of turbomachine100(FIG.1), e.g., temperature and dynamic pressure.

Referring toFIGS.27-33, another embodiment of the disclosure may provide an optical sensor300for a rotating blade stage120(FIG.2) of turbomachine100(FIG.1). As described, optical sensor300is configured for use coupled relative to circumferential interior surface152of casing122, rather than as a conventional radially extending sensor.FIG.27shows a perspective view of an optical sensor300in a mounting member180,FIG.28shows an exploded perspective view of optical sensor300and mounting member180, andFIG.29shows a perspective view of optical sensor300mounted in casing122with rotating blades132.FIGS.30-32show schematic cross-sections of optical sensor300according to a number of embodiments.

Embodiments of optical sensor300may include a housing310configured to be mounted relative to circumferential interior surface152of casing122of turbomachine100(FIG.1). Housing310may include a sender opening312and a receiver opening314, or a combined sender/receiver opening315. Housing310may be mounted relative to circumferential interior surface152according to any embodiment described herein.FIGS.27-30show housing310as a mounting member180, as described herein;FIG.31shows housing310mounted with use of an adhesive element172, as inFIG.6; andFIG.32shows housing310mounted in an at least partially embedded manner in a slot182in casing122, as inFIG.7. In terms of mounting member180, optical sensor300can be mounted as described for sensors170inFIGS.15and16.

Optical sensor300may also include at least one optical fiber320operatively coupled to housing310for communicating: an optical signal322for sending toward (e.g., transmitting toward) rotating blade stage120(FIG.29), i.e., rotating blades132thereof, and a return optical signal324reflected by rotating blade stage120, through casing122. Optical signal322may be sent through sender opening312or sender/receiver opening315(FIG.31), and return optical signal324may be received through receiver opening314or sender/receiver opening315(FIG.31). Openings312,314may be provided, as shown inFIGS.27-29, in housing310of optical sensor300. Alternatively, openings312,314may be provided, as shown inFIG.15, in mounting member180as openings220B. Similarly, sender/receiver opening315(FIG.31) may be provided, as shown inFIGS.27-29for openings312,314, or in mounting member180as a single opening220B.

In any event, optical fiber(s)320act as communications lead174, as described herein, and have a longitudinal shape, i.e., lengthwise shape, configured to follow circumferential interior surface152of casing122. That is, optical fiber(s)320have a radial height sufficiently short to allow their routing circumferentially along circumferential interior surface152. In one embodiment, shown inFIGS.30and32, optical fiber320includes a single optical fiber. In this case, optical fiber320is configured to allow two-way optical communications. In another embodiment, an example of which is shown inFIG.31, optical fiber320includes more than one optical fiber, e.g., a send optical fiber320A for optical signal322, and a receive optical fiber320B for return optical signal324.

Optical sensor300may include an optical signal redirecting element330configured to redirect optical signal322from optical fiber(s)320inwardly toward rotating blade stage120relative to casing122, and redirect return optical signal324reflected by rotating blade stage120into optical fiber(s)320. In one embodiment, as shown inFIGS.30-32, optical signal redirecting element330redirects optical signal322from optical fiber(s)320inwardly at a substantially perpendicular angle relative to an axis A (into and out of page) of turbomachine100(FIG.1) and a substantially radially (up/down page) direction relative to circumferential interior surface152of casing122toward rotating blade stage120. Optical signal322may pass through sender opening312or sender/receiver opening315(FIG.31). Optical signal redirecting element330also redirects return optical signal324reflected by rotating blade stage120into optical fiber(s)320extending along circumferential interior surface152of casing122. Return optical signal324may return through receiver opening314or sender/receiver opening315(FIG.31). Where optical fiber320includes more than one optical fiber320, as shown inFIG.31, signal redirecting element330is operatively coupled to send optical fiber320A and receive optical fiber320B.

Referring toFIGS.30-32, signal redirecting element330may take a variety of forms. In one embodiment, shown inFIG.30, signal redirecting element330may include a cleaved end332of optical fiber(s)320. Cleaved end332may be angled in any necessary manner to direct optical signals322,324, as described. In another embodiment, shown inFIG.31, signal redirecting element330may include a prism334. Prism334may be positioned, and have a reflective angled surface336angled, in any necessary manner to direct optical signals322,324, as described. In another embodiment, shown inFIG.32, signal redirecting element330may include a mirror338. Mirror338may be positioned and angled in any necessary manner to direct optical signals322,324, as described. While particular embodiments of signal redirecting element330have been described, it may alternatively include any other now known or later developed optical signal redirecting mechanism capable of directing optical signals322,324, as described.

FIG.33shows a schematic cross-sectional view of a portion of turbomachine100including an optical sensor300according to an alternative embodiment. In this embodiment, two optical fibers are provided, i.e., a send optical fiber320A and a receive optical fiber320B. Further, two optical signal redirecting elements330are provided: a first optical signal redirecting element330A for optical signal322and a second optical redirecting element330B for return optical signal324. As illustrated, first optical signal redirecting element330A is distanced circumferentially from second optical signal redirecting element330B along circumferential interior surface152of casing122. First optical signal redirecting element330A redirects optical signal322from optical fiber(s)320A inwardly at a first non-perpendicular angle β1relative to circumferential interior surface152of casing122toward rotating blade stage120. Second optical signal redirecting element330B redirects return optical signal324reflected by rotating blade stage120received at a second non-perpendicular angle β2relative to circumferential interior surface152of casing122into optical fiber(s)320B extending along circumferential interior surface152of casing122.

As observed inFIG.33, first and second non-perpendicular angles β1and β2are different. In one example, angle β1may be approximately 105°, and angle β2may be approximately 75°. Optical fibers320A,320B may be appropriately cleaved at approximately 37.5° and 142.5°. Optical sensor300according to this embodiment can thus create non-perpendicular optical signal send and receive angles that are not possible with conventional radially disposed sensors. Optical sensor300according to this embodiment can allow for clearance testing using a conventional time of arrival function for the clearance, as described in, for example, U.S. Pat. No. 4,049,349.

Optical sensor300has a very low radial profile, e.g., housing310and optical fiber(s)320, regardless of how mounted, and may have a radial height of no greater than two centimeters. Optical sensor300also allows many optical fibers320to be routed to the same location, allowing for better signal-to-noise ratio, higher data density, and redundancy.

Optical sensor300allows for a method of performing an optical analysis of a rotating blade stage120of turbomachine100that includes mounting optical sensor300, as described herein, to circumferential interior surface152of casing122of turbomachine100and performing the optical analysis of rotating blade stage120using the optical sensor. The optical analysis may include any now known or later developed analysis such as, but not limited to: a clearance test for rotating blade stage120relative to the circumferential interior surface152of casing122and/or a time-of-arrival testing for rotating blade stage120(testing blade vibration and frequency in a non-contact manner).

While individual optical sensors300are shown, it is understood that any number of optical sensors300can be provided, as described herein relative to sensors170. The optics used can vary depending on application and may include, for example, light or laser.

F. Use of Sensor Systems

Sensor systems160according to embodiments of the disclosure may be used for post-outage testing of a turbomachine100(FIG.1), prior to re-start and power generation. To this end, once sensor(s)170are coupled and communication leads(s)174are routed, a method according to embodiments of the disclosure may include re-assembling first portion142to second portion146of casing122, e.g., where portions are half-shells, half-shell casing148to half-shell casing150. Re-assembly may take any now known or later developed form such as lifting first portion142and lowering into place relative to second portion146, re-bolting them together and replacing any ancillary casing122equipment that may have been removed (e.g., pipes, insulation, flanges, lifting lugs, other instrumentation, bolts, or any other physical object in close proximity to the casing). Where rotor112is removed, it may be replaced in second portion146prior to the re-assembly. Turbomachine100(FIG.1) may then be activated in any now known or later developed fashion for post-outage calibration, trials, and testing.

In this regard, a method according to embodiments of the disclosure may include measuring an operational parameter of turbomachine100(FIG.1) using sensor(s)170during a post-outage testing operation of turbomachine100(FIG.1). The post-outage testing may include using any measurements obtained by sensor(s)170. For example, time of arrival for blade tip timing, blade tip clearance, dynamic pressure, static pressure, rotating vibration, stall detection (e.g., a compressor active stability management (CASM) sensor), rotor speed, optical rotor vibration, and temperature. In contrast to conventional radially positioned post-outage sensors, embodiments of the disclosure allow operating of turbomachine100(FIG.1) with sensor(s)170remaining in the turbomachine after the post-outage testing operation. That is, sensor(s)170do not need to be removed prior to operation. In addition, sensor(s)170may remain operational, allowing for continued measurements during operation of turbomachine100(FIG.1).

G. Other Applications of Mounting on Circumferential Interior Surface of Casing

The teachings of the disclosure can also be applied to other applications that benefit from mounting of structures to circumferential interior surface of casing122. In one alternative embodiment, a wireless sensor antenna system400for turbomachine100(FIG.1) including a rotating blade132including a passive sensor402thereon is provided. Small passive sensors402may be coupled to rotating blade(s)132to measure, for example, temperature, stress, strain, or other physical attribute(s) of the material of the rotating blade132to which attached. Sensors402may include any now known or later developed passive sensor that can be remotely powered, e.g., via an induction, capacitance, optical or radio frequency signal. Typically, such sensors402would have to be powered by circumferentially spaced power transmission elements, e.g., coils, and antennae, over a radial air gap between the rotating passive sensors and the stationary antennae/power coil. These sensors provide multiple, intermittent measurements as rotating blade132rotates, i.e., once per revolution, past a power providing and sensing location, but create only a near-static measurement. In order to obtain viable data on quickly changing physical properties (e.g., strain) measurements must be completed at a very high frequency, e.g., 300 MHz, which cannot be achieved on a per revolution basis. Further, the current passive sensors must be very close to the antenna that receive data from the sensors in order for them to work properly, which can be very challenging on a turbomachine. In contrast, a wireless sensor antenna system400according to embodiments to the disclosure provides an antenna and power transmission element that extend along at least a portion of the circumferential interior surface152, providing continuous (non-intermittent) measurements and real-time data about (possibly) quickly changing operational parameters.

Wireless sensor antenna system400includes an antenna410extending continuously along a circumferential interior surface152of casing122of turbomachine100that surrounds rotating blade132. Antenna410may be configured to receive a wireless signal412, which includes data indicative of the physical property of rotating blade132being measured by passive sensor402. Antenna410may also transmit a wireless signal414to communicate with passive sensor402, if desired. Antenna410may include any form of data transmission antenna element such as, but not limited to: electrical coils (inductive coupling), capacitors (capacitive coupling), magnetic coupling, or optical.

Wireless sensor antenna system400may also include a power transmission element420extending along at least portion of circumferential interior surface152of casing122to power passive sensor402. Power transmission element420may include any form of power transmission line or wire, e.g., a wire or an elongated sinusoidal or coiled wire, capable of electromagnetically powering passive sensor402through, for example, an inductance, capacitive, optical or radio frequency signal.

In one embodiment, antenna410and power transmission element420may extend along an entirety of circumferential interior surface152of casing122of turbomachine100(FIG.1) that surrounds stage120of rotating blades132. Here, passive sensor402can be continuously activated to provide data. In other embodiments, only a desired portion of circumferential interior surface152may be used. Antenna410and power transmission element420may extend through exit opening186(FIG.9) in casing122. Only one exit opening186(FIG.9) may be required.

Antenna410and power transmission element420may be mounted to circumferential interior surface152in any manner described herein. For example, they may be adhered to the surface as inFIG.6, or partially embedded as inFIG.7. In the example ofFIG.34, antenna410and power transmission element420are mounted in mounting member180positioned in slot182that extends at least partially circumferentially in circumferential interior surface152of at least a portion of casing122. Antenna410and power transmission element420may be mounted in mounting member180, e.g., in a passage240(FIG.18) therein. For example, they may be wires that extend in passage240(FIG.18) similar to communications leads174(FIG.17), or they may be printed wiring that is printed onto an interior surface of passage240. As described herein, mounting member180may include an arcuate portion212configured to mount in at least partially circumferentially extending slot182.

In operation according to a method of operation for wireless sensor antenna system400, antenna410and power transmission element420may be mounted, i.e., in any manner as described herein, along at least a portion of a circumferential interior surface152of casing122. Power transmission element420may power passive sensor402. A physical property of rotating blade132, e.g., strain, stress, etc., may be measured by powering passive sensor402with power transmission element420and receiving a wireless signal412from passive sensor402on rotating blade132at antenna410. Wireless signal412may include data indicative of the physical property.

IV. Mounting System for Tool to Form Slot on Circumferential Interior Surface of Casing

Referring toFIGS.35-44, embodiments of the disclosure may also include a mounting system500for a tool502for machining half-shell casing148,150of turbomachine100(FIG.1) and, in particular, circumferential interior surface152of half-shell casing148,150. In one illustrative application, mounting system500may mount tool502to form at least partially circumferentially extending slot182on circumferential interior surface152of casing122of turbomachine100(FIG.1), i.e., for use with mounting member180. Formation of an at least partially circumferentially extending slot182can be challenging. For example, casing portion142,146in the form of a half-shell casing148,150can be out-of-round when removed from, or exposed in, turbomachine100(FIG.1). For example, it can be warped, pinched, or sprung from its intended hemispherical shape. Consequently, forming a slot in circumferential interior surface152at a uniform depth can be very difficult. In addition, slot182must be formed in a uniform manner relative to mounts164for a pair of stages120(FIG.2) of nozzles126(FIG.2) in circumferential interior surface152of casing122, e.g., slot182may need to be equidistant from each mount164. Manually guiding a tool to create slot182that has uniform depth and consistent axial spacing relative to mounts164can be very difficult.

While the teachings of the disclosure will be described mainly relative to forming slot182, it will understood that mounting system500may be employed to machine other features in half-shell casings148,150, e.g., radially extending holes and/or other features. Tool502may be powered in any known fashion, e.g., via an electric motor, hydraulics, pneumatics, etc., and may include any ancillary transmission structures (not shown) necessary to transmit power to a working element thereof, e.g., a machining element.

FIGS.35and36show perspective views of mounting system500coupled to a half-shell casing148,150of a turbomachine.FIG.35shows half-shell casing148,150standing vertically, e.g., on a floor in a manufacturing setting or, advantageously, on a floor at a power plant where the half-shell casing148,150is used in a turbomachine (FIG.1). InFIG.35, half-shell casing148,150has been removed from turbomachine100(FIG.1).FIG.36shows half-shell casing148,150in a generally horizontal position, e.g., a lower half-shell casing150remaining in position in turbomachine100(FIG.1) after removal of upper half-shell casing148, or either half-shell casing148,150set on a floor, open upwardly. It is noted that mounting system500can be employed regardless of how half-shell casing148,150is physically situated.FIG.37shows a detailed perspective view of tool mount520according to theFIG.36embodiment.

As shown inFIGS.35and36, mounting system500may include a base frame510including a mounting element511configured to fixedly mount base frame510to half-shell casing148,150. Base frame510may include any form of mechanical frame having sufficient strength and rigidity to resist forces applied thereto by tool502and a tool mount520, described herein. In the example shown inFIGS.35and36, base frame510may include a first pair of opposing rails512coupled to a second pair of opposing rails514, creating a box frame. However, base frame510can have a wide variety of alternative shapes and frame parts. Rails512,514may be coupled in any desired manner, e.g., welding, mechanical fasteners, integral formation, etc. Base frame510spans at least a portion of half-shell casing148,150, i.e., it extends at least a portion across from one side of half-shell casing to the other side. In the example shown, base frame510spans an entirety of half-shell casing148,150, but that may not be necessary in all instances, i.e., base frame510could be cantilevered over circumferential interior surface152. Base frame510may be coupled to half-shell casings148,150by mounting element511. Mounting element511can take variety of forms such as, but not limited to, clamps or other mechanical fasteners518for coupling base frame510to flanges156of half-shell casings148,150.

Mounting system500also includes a tool mount520including a first end522pivotally coupled to base frame510to pivot about a pivot axis PA that is substantially parallel (i.e., on-axis with rotor centerline or with some tolerance from being off-center (e.g., within +/−3°)) relative to an axis A of half-shell casing148,150, and a second end524configured to couple to and position tool502for machining half-shell casing148,150. Tool mount520may be pivotally coupled to base frame510in a number of ways. As shown inFIG.35, tool mount520, e.g., a base member554thereof, may be fixedly coupled to a pivot member530, and pivot member530may rotate relative to base frame510. InFIG.35, pivot member530may be rotatably coupled to base frame510by a pair of bearings532fixedly coupled to base frame510, e.g., opposing rails514. Pivot member530includes mounts531that couple it to tool mount520. In this case, a transmission538may be coupled to pivot member530to rotate it and tool mount520, as will be described herein.

In an alternative embodiment, as shown inFIGS.36and37, tool mount520may be rotatably coupled to pivot member530to rotate about pivot member530, and pivot member530may be fixedly coupled to base frame510. Here, pivot member530includes a pair of fixed mounts534that fixedly couple to base frame510, e.g., rails512, and a pair of bearings536are coupled to tool mount520, e.g., a base member554thereof, that can receive pivot member530therein to allow tool mount520to rotate about pivot member530and pivot relative to base frame510. With this arrangement, tool mount520can be manually pushed to rotate about pivot member530. In any event, as shown by arrows inFIGS.35and36, tool mount520may rotate the entire extent of circumferential interior surface152, e.g., 180°, or a smaller portion thereof.

Pivot axis PA, as may be defined by pivot member530, positions tool mount520that holds tool502at or near a center of half-shell casings148,150, i.e., at or near axis A. As will be further described, however, pivot axis PA does not necessarily have to be at an exact center of half-shell casing148,150, i.e., some tolerance from being off-center is allowed. The level of tolerance may vary depending on a number of factors such as, but not limited to, attributes of the half-shell casings148,150such as size, shape/out-of-roundness; or axial position of space162to be machined. Pivot axis PA and pivot member530may extend substantially parallel relative to an axis A of half-shell casing148,150. Pivot axis PA and pivot member530may be positionally adjustable in any of a variety of ways. In one embodiment, base frame510may be laterally adjustably positioned relative to half-shell casings148,150(left-to-right as shown inFIGS.35-36) by mounting element511so as to adjust a radial position of pivot axis PA and pivot member530relative to half-shell casings148,150. Alternatively, pivot axis PA and pivot member530may be laterally adjustable relative to base frame510, e.g., by way of clamps or other mechanical fasteners (not shown). A longitudinal position of tool mount520relative to half shell casings148,150, i.e., position along axis A illustrated as vertical inFIG.35and horizontal inFIG.36, may be based on a mounting position of base frame510relative to half-shell casing148,150. Alternatively, as will be described, a longitudinal adjust system (not shown) could also be employed to adjust a position of tool mount520relative to base frame510.

FIG.38shows a radial end perspective view of tool mount520including a tool positioning mount540coupled to second end524. Tool positioning mount540positions tool502relative to tool mount520. As illustrated, tool502includes a machining element542to machine, for example, slot182(FIG.18) in at least a portion of a circumferential interior surface152(FIG.18) of half-shell casing148,150(FIG.18). Machining element542may include any now known or later developed machining element (e.g., a bit, disk, jet, EDM wire, laser for milling, drilling, grinding, cutting, etc.) capable of forming slot182(FIG.18).

Referring again toFIGS.35-37, tool mount520may further include a biasing system550for biasing second end524(and tool positioning mount540(FIG.38)) of tool mount520radially outward from first end522towards circumferential interior surface152of casing122. Biasing system550can take a variety of forms, as will be described herein.

In theFIGS.35-37embodiments, tool mount520may include a telescoping frame552(FIG.37) including a base member554at first end522pivotally coupled to base frame510. As will be described, telescoping frame552can be radially outwardly biased by biasing system550. Base member554may be pivotally coupled to base frame510by way of pivot member530being coupled thereto, as described herein. Base member554may include a linear bearing556. Telescoping frame552also includes a telescoping member560received by linear bearing556and extending to second end524. Telescoping member560is fixedly coupled to tool positioning mount540at second end524, e.g., by mechanical fasteners561(FIG.38). In the example shown, base member554includes four linear bearings556, and the telescoping member includes four telescoping members560, each telescoping member560received in a respective linear bearing556of base member554and extending to second end524. It is emphasized that telescoping frame552may include more or less telescoping members560and linear bearings556. Further, telescoping member552may have alternative forms than the rods shown, e.g., they can have other cross-sectional shapes.

Telescoping member(s)560is/are biased radially outward from first end522and pivot member530towards circumferential interior surface152of half-shell casing148,150by biasing system550. In this embodiment, biasing system550includes a bias adjusting system570including a first member572including an opening574through which a telescoping member560slidably moves, i.e., opening574may simply be an opening in first member572or it may include a linear bearing. As shown, first member572is spaced from base frame510, i.e., along telescoping member(s)560. Bias adjusting system570also includes a second member576positioned radially outward of first member572and fixedly mounted to telescoping member(s)560, e.g., by welding or mechanical fasteners578. Bias adjusting system570includes a spring580positioned to apply a force F between first member572and second member576, forcing second end524of tool mount520, tool positioning mount540, and tool502radially outward towards circumferential interior surface152. In one example, spring580may be provided about each telescoping member560between first member572and second member576. It will be recognized that spring580may have other locations and numbers so long as force F can be applied between first member572and second member576.

Bias adjusting system570includes a position adjuster582operably coupled to first member572and second member576to: adjust a distance D between first member572and second member576and a radial position of tool502relative to circumferential interior surface152of half-shell casing148,150, and/or to adjust force F applied by biasing system550to tool502, i.e., via telescoping member(s)560, by adjusting distance between base member554and first member572. Force F may be applied at any level to ensure tool502machines circumferential interior surface152, e.g., sufficient force to prevent chattering of tool502. In one example, position adjuster582includes a (manual) jack screw584. However, position adjuster582may include any now known or later developed linear adjusting system, e.g., a hydraulic or pneumatic ram, a motorized jack screw, etc.

Referring toFIG.39, an alternative embodiment of telescoping frame552and biasing system550may include one of a hydraulic ram and a pneumatic ram590operably positioned between base member554and second end524of tool mount520. While four rams590are shown, any number may be employed. Each ram590may include a telescoping member592configured to apply force F to second end524of tool mount520, and to tool502. A power controller594may be provided to control each ram590in a known fashion.

Referring toFIGS.38and40, any of the embodiments shown inFIGS.35-39may also include a guide system600coupled to tool positioning mount540to guide machining element542relative to circumferential interior surface152(FIGS.35-36) of half-shell casing148,150(FIGS.35-36), e.g., to machine slot182(FIGS.35-36) in circumferential interior surface152of the half-shell casing.FIG.40shows tool502forming an at least partially circumferentially extending slot182into circumferential interior surface152. Guide system600may include any form of surface engaging elements to direct tool502in a desired manner. In an example shown inFIG.38, guide system600may include a plurality of roller bearings602coupled to tool positioning mount540with each roller bearing602positioned to engage, and position machining element542relative to, an axial facing surface610(FIG.40) of circumferential interior surface152of half-shell casing148,150. Roller bearings602may include any form of roller bearing capable of withstanding the forces applied to tool positioning mount540.

Guide system600may also include a plurality of surface bearing elements612coupled to tool positioning mount540with each surface bearing element612positioned to engage and position machining element542relative to a radially inward facing surface614(FIG.40) of circumferential interior surface152(FIG.40) of half-shell casing148,150(FIG.40). Surface bearing element612may include any form of bearing capable of withstanding the forces applied to tool positioning mount540. Surface bearing elements612may include but are not limited to a ball transfer (as shown) or an air bearing fed by compressed air.

FIG.38also shows an adjustment system620configured to adjust a position of at least one of the plurality of roller bearings602relative to tool positioning mount540. Adjustment system620can include any form of mechanism to change the position of roller bearings602relative to tool positioning mount540. In the example shown, adjustment system620includes a sliding frame622upon which roller bearing(s)602are mounted. Sliding frame622is slidably positioned on rails624and can have its position adjusted relative to tool positioning mount540by an adjustable screw(s)626. The position of roller bearings602could also be adjustable by, for example, providing a set number of mounting locations therefor in tool positioning mount540. InFIG.38, roller bearings602on the right side of tool positioning mount540are coupled into a base plate541of tool positioning mount540, e.g., via threaded holes621. This set of roller bearings602can be moved coarsely to other holes621in plate541. On the left side of base plate541, another set of roller bearings602are coupled into sliding frame622, which can be moved toward or away from the other set of roller bearings602on the right side of base plate541. These two sets of roller bearings602clamp to opposing axially facing surfaces610of a mount164. Once clamped, the opposing roller bearings602guide machining element542of tool502, maintaining a constant axial machining position thereof.

Since mounts164vary in width, roller bearings602are mounted on sliding frame622to accommodate the varying sizes. Since sliding frame622has fine adjustment, e.g., via adjustable screw(s)626, its roller bearings602can also clamp down on and apply compressive force to mount164. Roller bearings602maintain the axial position of tool502while surface bearing elements612maintain the radial position. At least one set of roller bearings602is moveable to allow for positioning of tool502, e.g., to allow drawing of the tool into the proper cutting position.

Referring toFIG.41, in another embodiment, half-shell casing148,150may not include circumferentially extending structure, such as mounts164, or the structure may not be where it can be used to guide tool502. For example, for the first three stages in the lower portion ofFIG.5, variable vane, circular openings168are employed, so there is no circumferentially extending structure with axially facing surfaces as with mounts164. In either case, as shown inFIG.41, embodiments of the disclosure may provide a jig623coupled to circumferential interior surface152of half-shell casing148,150. Jig623may include a curved member625that extends along circumferential interior surface152and provides a guide surface(s)627for guiding tool502. While one jig623is shown, any number may be employed. Jig623may be mounted to half-shell casing148,150in a similar fashion to base frame510, e.g., with clamps or other fasteners.

Tool positioning mount540may couple to second end524of tool mount520and may include guide system600, as described herein. Referring toFIGS.38,40and41, in this case, each roller bearing602may be positioned to engage and position machining element542relative to jig623and/or any axial facing surface610(FIG.40) of circumferential interior surface152of half-shell casing148,150. Similarly, each surface bearing element612may be positioned to engage and position machining element542relative to jig623, i.e., guide surface(s)627, and a radially inward facing surface614(FIG.40) of circumferential interior surface152of half-shell casing148,150. Guide system600(FIG.38) may include adjustment system620(FIG.38), as described herein.

Referring toFIGS.35and42, tool mount520may be rotated in a number of ways. As noted, inFIG.36, tool mount520can be manually pushed to turn about pivot member530. Alternatively, inFIG.35, transmission538in the form of a manual gear box630may be operably coupled to pivot member530to turn pivot member530and tool mount520. Manually turning a handle632may turn pivot member530and tool mount520. In another embodiment, shown inFIG.42, transmission538may include a rotating actuator634operably coupled to tool mount520, i.e., pivot member530, to rotate tool mount520and tool502about the pivot axis PA to circumferentially machine slot182in circumferential interior surface152of half-shell casing148,150. Rotating actuator634may include any form of motorized system with any necessary transmission to turn pivot member530at the desired rate. Rotating actuator634may be coupled to base frame510in any fashion.

With reference toFIG.43, a longitudinal adjust system640for changing a position of mounting system500along axis A of half-shell casing148,150is illustrated. As noted, a longitudinal position of tool mount520relative to half shell casings148,150, i.e., position along axis A illustrated as vertical inFIG.35and horizontal inFIG.36, may be based on a mounting position of base frame510relative to half-shell casing148,150. Alternatively, as shown inFIG.43, a longitudinal adjust system640can be employed to automatically adjust a position of tool mount520relative to base frame510. Longitudinal adjust system640may include any system for linearly moving one element relative to another.

In one example shown inFIG.43, longitudinal adjust system640may include a linear actuator642, e.g., hydraulic or pneumatic ram, a motorized worm gear, etc., coupled at one end to half-shell casing148,150, e.g., with fasteners, and coupled at the other end to base frame510, allowing linear adjustment of base frame510relative to half-shell casing148,150. Alternatively, tool502may be movably mounted on a carriage on rails (not shown), e.g., with bearings on shaft or sliders within guides.

In operation, after half-shell casing148,150is exposed by, for example, removal from turbomachine100(FIG.1) for upper half-shell casing148, or removal of rotor112and remaining in place for lower half-shell casing150, mounting system500is coupled to half-shell casing148,150. See e.g.,FIGS.35,36,40and41. Mounting system500can be coupled to half-shell casing148,150, as described herein, using mounting element511. Once mounted, tool mount520is pivotally coupled to pivot relative to base frame510and about pivot axis PA. Tool mount520can be rotated such that machining element542is circumferentially outside of flange156(FIGS.35,36). Tool502can then be activated, and tool mount520pivoted to direct machining element542to machine slot182into at least a part of circumferential interior surface152. Tool mount520can be pivoted to move tool502along circumferential interior surface152.

As tool mount520pivots, guide system600on tool positioning mount540and bearings602and surface bearing elements612thereof may guide tool502and machining element542in a desired manner to ensure proper axial and radial positioning of machining element542. Biasing system550ensures tool502and machining element542maintain proper radially outward position and radially outward force F (e.g.,FIGS.36,37). Pivot axis PA maybe aligned with axis A of turbomachine100(FIG.1) and half-shell casing148,150. However, biasing system550allows for pivot axis PA to be not exactly aligned, but simply parallel, with axis A. Any number of passes of tool502may be completed to form slot182of a desired circumferential length. As described herein, once complete, slot182may receive mounting member(s)180for sensor(s)170.

Referring toFIG.44, in another embodiment of mounting system500, tool502may include a drill machining element650to machine a radially extending hole652through half-shell casing148,150. Here, tool mount520telescopes via a linear actuator654, to move drill machining element650at second end524of tool mount520radially outward and radially through half-shell casing148,150. In another embodiment, tool mount520may include telescoping frame552, as described relative toFIGS.35-37. In this case, a tool502with machining element542may be replaced (leaving base plate541connected to the end of the telescoping frame) with a tool502with a drill machining element650. Alternatively, tool mount520may include a hydraulic or pneumatic ram590(shown inFIG.44), as described relative toFIG.39. Mounting system500may also include a rotating actuator, e.g., a manual or motorized transmission538, operably coupled to tool mount520to rotate the tool mount and tool502about pivot axis PA to more than one circumferential location (2shown inFIG.44) relative to circumferential interior surface152of half-shell casing148,150.

At each location, drill machining element650can be directed to drill radially extending hole652through half-shell casing148,150. Thus, mounting system500may also allow a radially extending hole652to be machined through half-shell casing148,150at each of a plurality of circumferential locations. Rather than repeatedly moving a conventional drilling tool about exterior surface154of half-shell casing148,150and addressing all of the challenges involved with doing so, mounting system500can be used to create any number of radially extending holes652in a reliable and repeatable manner, perhaps with the aid of angular-positioning measurement devices or simple analog devices such as a protractor or angle finder. Mounting system500may only need to be mounted once rather than numerous times, as is necessary with the conventional approach. Further, since mounting system500provides a controlled, circumferential rotation of tool502, drilling radially extending holes652with the incorrect pitch angle can be avoided. Conventional radial sensors (not shown) can be mounted in radially extending holes652in any known fashion.

V. Conclusion

Embodiments of the disclosure provide various embodiments of methods, systems and ancillary structures and tools for enabling use of sensor(s) within a circumferential interior surface of a turbomachine casing. The described systems and methods allow control of both axial and circumferential positions (as well as pitch angle) of the sensors to improve the integrity of the measurements.

Since embodiments of the disclosure provide the sensor systems on the interior of the casing, ancillary equipment on the exterior of the casing need not be removed or worked around. Obstacles like pipes, insulation, flanges, lifting lugs, other instrumentation, bolts, or any other physical object in close proximity to the casing, can be left in place. The obstacles also no longer prevent the positioning of a sensor in the optimal location, e.g., they can be asymmetric, clustered, equally spaced, etc.

In addition, any number of sensors can be used, increasing the data volume that is collected. The sensors need not be removed after use and may, depending on type, continue to be used during operation of the turbomachine. Different types of sensors can be used in different locations and/or in the same location without concern about drilling too many holes in the casing. The sensors are also not exposed from the exterior surface of the casing, reducing their susceptibility to damage. Embodiments of the disclosure also provide an improved optical sensor capable of use on the interior surface of the casing and a wireless sensor antenna system enabling improved passive sensors.

Embodiments of the disclosure also eliminate the need for precise machining of radial holes in a factory or machine shop, allowing installation of the sensor systems (internal or radially extending) in the field. The tool described herein is highly portable, quick and easy to use and setup, and provides repeatable and accurate formation of the necessary slots or holes. The internal sensor systems thus result in better measurement certainty, better data, and less misinterpretation of measurements. The number of holes in the casing necessary to implement the internal sensor systems are also drastically reduced compared to conventional systems, reducing the possibility of leaks. The tool can also be used to form radially extending holes for conventional radially extending sensors in a more efficient and precise manner than conventional drilling. The tool thus removes conventional concerns over whether radial mounting holes are oriented properly and eliminates guesswork and the need to verify the radial orientation of the mounting holes.

The foregoing drawings show some of the processing associated according to several embodiments of this disclosure. It should be noted that in some alternative implementations, the acts may occur out of the order noted or, for example, may in fact be executed substantially concurrently or in the reverse order, depending upon the act involved.

Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise. “Approximately” as applied to a particular value of a range applies to both values, and unless otherwise dependent on the precision of the instrument measuring the value, may indicate +/−10% of the stated value(s).

The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the present disclosure has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the disclosure in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The embodiment was chosen and described in order to best explain the principles of the disclosure and the practical application and to enable others of ordinary skill in the art to understand the disclosure for various embodiments with various modifications as are suited to the particular use contemplated.