DIRECTIONAL WATER JET CLEANING OF ENGINE BLADES

Aspects of the disclosure are directed to a probe for servicing a turbine blade of an engine. The probe includes hardware configured to couple to a fluid source, a stem, and an opening included in the stem, where the opening is oriented at a non-zero valued angle relative to a length of the stem. In some embodiments, a system includes a turbine blade of an engine, a machine that captures an image of the turbine blade, and a probe that includes a stem with an opening formed in the stem, where the opening is oriented at a non-zero valued angle relative to a length of the stem and removes debris from the turbine blade captured in the image based on an ejection of a pressurized fluid from the opening, where the debris is located on an interior surface of the turbine blade.

This application claims priority to Singapore Patent Appln. No. 10201707125Y filed Aug. 31, 2017, which is hereby incorporated by reference in its entirety.

BACKGROUND

Gas turbine engines, such as those which power aircraft and industrial equipment, employ a compressor to compress air that is drawn into the engine and a turbine to capture energy associated with the combustion of a fuel-air mixture in a combustor. The engine hardware is typically arranged about a longitudinal axis/centerline. The turbine and the compressor architectures utilize alternating stationary and rotating structures, where a pairing of stationary structure and rotating structure is frequently referred to as a stage. The rotating structure is formed as a rotatable disk with blades that extend radially therefrom.

The turbine blades, which are located downstream of the combustor (relative to the direction of airflow through the engine), are subject to elevated temperatures due to exposure to the output of the combustion. The turbine blades are cooled in order to promote efficiency/reliability in operation and extend the operational service lifetime of the turbine blades. U.S. Pat. No. 7,753,061 (hereinafter referred to as the '061 patent) describes various cooling structures/members of a turbine blade; the contents of the '061 patent are incorporated herein by reference.

When the engine is operated, debris may be ingested by the engine. For example, in the context of an engine of an aircraft, debris generation may be particularly acute during take-off and landing operations. The debris may be ingested by the turbine blade cooling structures, such as for example by cooling holes in an airfoil of the turbine blade. The debris, which may manifest itself as silica or calcium-rich deposits/residue, may adhere to the internal walls/ribs of the turbine blade. The debris has an increased tendency to adhere to the walls/ribs at elevated temperatures. Given current trends towards operating engines at increasing temperatures, the amount/rate of accumulation of debris inside the turbine blade is expected to increase.

The efficiency of the cooling of the turbine blade may be reduced/compromised by the presence of the debris, as the debris has a tendency to impede the flow of air through the turbine blade. The accumulation of the debris also tends to incrementally increase the weight of the engine, thereby negatively impacting fuel efficiency. In this respect, a turbine blade may be subject to cleaning during, e.g., a maintenance/inspection procedure in an effort to remove the debris from the turbine blade. The '061 patent describes subjecting a turbine blade to an autoclave, ultrasonic, and flushing process to remove the debris.

As described in the '061 patent, during the flushing process a probe is inserted into a cavity of the turbine blade and a pressurized fluid (e.g., water) is ejected from an opening at an end of the probe and into the cavity. Referring toFIG. 2, a schematic representation of a probe202of the type described in the '061 patent is shown. A fluid source208is coupled to a first, proximal end214of the probe202. The fluid from the fluid source208enters the first end214, traverses the length of the probe202, and is ejected from an opening236at a second, distal end242of the probe202. The fluid that is ejected from the opening236is used to clean the turbine blade.

As shown inFIG. 2, the opening236is oriented along the axial length/span of the probe202. Stated differently, the fluid is ejected from the opening236in a direction aligned with the axial length of the probe202. The orientation of the opening236is ineffective in terms of a removal of debris at various locations of the turbine blade.

BRIEF SUMMARY

Aspects of the disclosure are directed to a probe for servicing a turbine blade of an engine, comprising: hardware configured to couple to a fluid source, a stem, a first opening included in the stem, and a second opening included in the stem, where the first opening is oriented at a non-zero valued angle relative to a length of the stem, and where the second opening is included in an end of the stem. In some embodiments, the angle is a right angle. In some embodiments, the first opening is sized to remove debris from the turbine blade. In some embodiments, the end is a distal end relative to the fluid source.

Aspects of the disclosure are directed to a system comprising: a turbine blade of an engine, a machine that captures an image of the turbine blade, and a probe that includes a stem with an opening formed in the stem, where the opening is oriented at a non-zero valued angle relative to a length of the stem and removes debris from the turbine blade captured in the image based on an ejection of a pressurized fluid from the opening, where the debris is located on an interior surface of the turbine blade. In some embodiments, the machine is an x-ray machine and the image is an x-ray image. In some embodiments, the angle is a right angle. In some embodiments, the debris is located on a rib of the turbine blade. In some embodiments, the turbine blade includes a cooling hole, and the debris enters the turbine blade via the cooling hole. In some embodiments, the system further comprises a processor, and a non-transitory storage device that stores instructions that, when executed by the processor, causes the system to: identify a region in which the debris is located. In some embodiments, the region is identified based on a comparison of the image with at least a second image. In some embodiments, the machine captures a second image of the turbine blade subsequent to the removal of the debris. In some embodiments, the second image is an image of the turbine blade taken after the blade was manufactured that is stored in a non-transitory storage device.

Aspects of the disclosure are directed to a method comprising: obtaining an image of a turbine blade, identifying, based on the image, a region in the interior of the turbine blade that includes debris, inserting a probe into the turbine blade, the probe including a stem with an opening that is oriented at a non-zero valued angle relative to a length of the stem, and activating a fluid source coupled to the probe to remove the debris. In some embodiments, the method further comprises obtaining a second image of the turbine blade subsequent to activating the fluid source, and determining that the debris is removed based on an examination of the second image. In some embodiments, the method further comprises rotating the probe to direct the opening towards the debris. In some embodiments, the method further comprises adjusting an insertion length of the stem based on an identification of the location of the region. In some embodiments, the step of determining that the debris is removed based on an examination of the second image includes comparing the second image to a third image, where the third image is an image of the turbine blade after it was last cleared of debris. In some embodiments, the step of determining that the debris is removed based on an examination of the second image includes comparing the second image to a third image, where the third image is an image of the turbine blade after it was originally manufactured. In some embodiments, the step of obtaining an image includes using an X-ray machine to take the image and the step of obtaining a second image includes using an X-ray machine to take the second image

DETAILED DESCRIPTION

It is noted that various connections are set forth between elements in the following description and in the drawings (the contents of which are incorporated in this specification by way of reference). It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. A coupling between two or more entities may refer to a direct connection or an indirect connection. An indirect connection may incorporate one or more intervening entities or a space/gap between the entities that are being coupled to one another.

Aspects of the disclosure may be applied in connection with a gas turbine engine.FIG. 1is a side cutaway illustration of a geared turbine engine10. This turbine engine10extends along an axial centerline12between an upstream airflow inlet14and a downstream airflow exhaust16. The turbine engine10includes a fan section18, a compressor section19, a combustor section20and a turbine section21. The compressor section19includes a low pressure compressor (LPC) section19A and a high pressure compressor (HPC) section19B. The turbine section21includes a high pressure turbine (HPT) section21A and a low pressure turbine (LPT) section21B.

The engine sections18-21are arranged sequentially along the centerline12within an engine housing22. Each of the engine sections18-19B,21A and21B includes a respective rotor24-28. Each of these rotors24-28includes a plurality of rotor blades arranged circumferentially around and connected to one or more respective rotor disks. The rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective rotor disk(s).

The fan rotor24is connected to a gear train30, for example, through a fan shaft32. The gear train30and the LPC rotor25are connected to and driven by the LPT rotor28through a low speed shaft33. The HPC rotor26is connected to and driven by the HPT rotor27through a high speed shaft34. The shafts32-34are rotatably supported by a plurality of bearings36; e.g., rolling element and/or thrust bearings. Each of these bearings36is connected to the engine housing22by at least one stationary structure such as, for example, an annular support strut.

As one skilled in the art would appreciate, in some embodiments a fan drive gear system (FDGS), which may be incorporated as part of the gear train30, may be used to separate the rotation of the fan rotor24from the rotation of the rotor25of the low pressure compressor section19A and the rotor28of the low pressure turbine section21B. For example, such an FDGS may allow the fan rotor24to rotate at a different (e.g., slower) speed relative to the rotors25and28.

During operation, air enters the turbine engine10through the airflow inlet14, and is directed through the fan section18and into a core gas path38and a bypass gas path40. The air within the core gas path38may be referred to as “core air”. The air within the bypass gas path40may be referred to as “bypass air”. The core air is directed through the engine sections19-21, and exits the turbine engine10through the airflow exhaust16to provide forward engine thrust. Within the combustor section20, fuel is injected into a combustion chamber42and mixed with compressed core air. This fuel-core air mixture is ignited to power the turbine engine10. The bypass air is directed through the bypass gas path40and out of the turbine engine10through a bypass nozzle44to provide additional forward engine thrust. This additional forward engine thrust may account for a majority (e.g., more than 70 percent) of total engine thrust. Alternatively, at least some of the bypass air may be directed out of the turbine engine10through a thrust reverser to provide reverse engine thrust.

FIG. 1represents one possible configuration for an engine10. Aspects of the disclosure may be applied in connection with other environments, including additional configurations for gas turbine engines. Aspects of the disclosure may be applied in connection with non-geared engines.

Referring toFIG. 3, a blade300in accordance with aspects of this disclosure is shown. The blade300may be incorporated as part of one or more sections of an engine, such as for example the turbine section21ofFIG. 1.

The root of the blade300(which is the portion of the blade300that is seated in a rotor/disk of the engine) may include one or more ports, such as for example a first port304a, a second port304b, and a third port304c. During engine operation, cooling air from, e.g., the compressor section may be supplied to the blade300via the ports304a-304c. The cooling air may be exhausted by/exit the blade300via one or more cooling holes310. The cooling holes310may be located proximate at an aft-most edge314of the blade300.

The interior of the blade300may be separated into one or more cavities by one or more wall/ribs, such as for example a first rib318a, a second rib318b, and a third rib318c. The rib318cmay at least partially define the port304band the port304c. The rib318cmay have a given dimension/length L1.

During operation of an engine, debris may be ingested by the cooling holes310. The debris may adhere to one or more surfaces of the blade300, such as for example to surfaces of one or more of the ribs318a-318c. The blade300may be subject to a maintenance activity/procedure to remove the debris from the blade300.

As described above, the removal of debris may be facilitated by the use of a probe as part of a flushing process. InFIG. 3, a probe350is shown as being at least partially inserted into the blade300via the port304a. For example, the probe350is shown as being inserted into the blade300at an insertion length L2, which in some embodiments, may be greater than the length L1. The particular value for the insertion length L2may be based on a location of debris in the blade300, where the location may be determined as described further below.

Referring toFIG. 4A, a closer view of the probe350ofFIG. 3is shown. The probe350may include hardware (e.g., a threaded screw/section406) that may be configured to couple the probe350to a fluid source or manifold as would be known to one of skill in the art. See, e.g., the aforementioned '061 patent for examples of a probe connected to a fluid manifold/fluid source; see alsoFIG. 2of this disclosure (fluid source208). The probe350may include a stem418, where the stem418is the portion of the probe350that is inserted into the blade300as shown inFIG. 3. The stem418may be hollow to allow fluid to traverse at least a portion of the length/span of the stem418.

A closer view of the stem418is shown inFIG. 4B. Proximate an end442of the probe350(where the end442is a distal end relative to the fluid source/manifold) an opening456may be formed/included in the stem418. In contrast to the opening236ofFIG. 2, the opening456is not oriented along the length/span of the probe350/stem418. Instead, the opening456is oriented at a non-zero valued angle (e.g., a right angle or perpendicular) relative to the length/span of the probe350/stem418.

Referring toFIGS. 3, 4A, and 4B, the non-zero valued angle/orientation of the opening456relative to the length/span of the probe350/stem418may enable a removal of debris located at a mid-span of the blade300. For example, and as shown inFIG. 3, the opening456may be used to remove debris from a mid-span of the rib318b. In contrast, the probe202ofFIG. 2(with opening236) would not be able to effectively remove debris at a mid-span of the blade300. Instead, the effectiveness of the probe202ofFIG. 2would be limited to debris removal located on, or proximate to, the end wall354ofFIG. 3.

WhileFIG. 4Billustrates a stem418as including a single opening456, more than one opening may be included in some embodiments. For example, in some embodiments a probe may include both the opening456in the stem418as shown inFIG. 4Band an opening at the end442(analogous to the opening236ofFIG. 2). In such embodiments, one of the openings may be selectively closed if that opening is not needed.

In some embodiments, the probe350(e.g., the stem418) may be made of one or more materials. For example, the probe350may include a high strength steel. In some embodiments, the steel may correspond to type 304 stainless steel (also referred to in the art as “18-8” stainless steel because of its composition—18 percent chromium and 8 percent nickel). The material that is used for the probe350may be selected to withstand hoop stress generated by the high pressure fluid, where the pressure of the fluid may be within a range of 5000 psi-10000 psi (approximately within a range of 34 Megapascal-69 Megapascal).

One or more techniques may be used to determine a location of debris that may be internal to a blade (e.g., the blade300ofFIG. 3). For example, a blade may be x-rayed to determine if debris is present, and if it is, where the debris is located.FIG. 5Aillustrates a first x-ray image500of a blade. A portion of the blade, denoted by the circled region510, may include (an aggregate of) debris. A second x-ray image500′ of the blade is shown inFIG. 5B. The circled region510′ denotes a substantial absence of debris.

In some embodiments, the image500′ may correspond to an initial image of the blade, such as for example an image taken after the blade is originally manufactured. Alternatively, the image500′ may correspond to an image of the blade taken after the blade is subjected to a flushing process via the probe350. Irrespective, the image500′ may correspond to a baseline image that may be used in a comparison with the image500to determine a probable location of debris (e.g., the region510). Image processing software may be used to compare the images500and500′ and identify the region510.

Once region510is identified as likely including debris, the probe350(and in particular, the opening456) may be targeted to that region510. For example, the probe350/stem418may be rotated, as needed, so as to direct the opening456towards the region510/debris. Additionally, the insertion length L2(seeFIG. 3) may be determined/adjusted based on the identification of the region510. Alternatively, if a number of different probes of various dimensions (e.g., lengths) are available, a given probe of a given dimension may be selected corresponding to the location of the region510. More generally, the particular type of probe that is used may be based on one or more parameters, such as for example a type (e.g., make and model number) of the blade, a location of the region that likely includes debris, an amount/density of the debris, etc.

Turning toFIG. 6, a computing system600that may be used in some embodiments is shown. The computing system600may be used to at least partially automate removal of debris from one or more blades.

The system600may include a processor602and a memory608. The memory608may store instructions (e.g., instructions614a) that, when executed by the processor602, may cause the system600to perform one or more methodological acts, such as one or more of the acts described herein. At least a portion of the instructions (e.g., instructions614b) may be stored on a computer-readable medium (CRM)620, such as for example a non-transitory CRM. The instructions614bof the CRM620may be used as an alternative to, or in addition to, the use of the instructions614aof the memory608. One or both of the memory608and the CRM620, taken individually or collectively, may be referred to as a storage device. Much like the CRM620, the storage device may be non-transitory in nature.

In some embodiments, the system600may include one or more input/output (I/O) devices626. The I/O devices626may provide an interface between the system600and one or more other components or devices. The I/O devices626may include one or more of a graphical user interface (GUI), a display screen, a touchscreen, a keyboard, a mouse, a joystick, a pushbutton, a microphone, a speaker, a transceiver, an x-ray device/machine, a camera, etc. The I/O devices626may be used to output data in one or more formats (e.g., a visual or audio rendering).

The memory608may store data634. The data634may include an identification of a blade, one or more images of the blade (e.g., a first, baseline image of the blade and a second image of the blade during a servicing of the blade), an identification of one or more regions of the blade that likely include debris, an identification of one or more probes that may be used to remove debris from the blade, an identification of an insertion length associated with a probe or a degree by which the probe should be rotated to target the debris, etc.

The system600is illustrative. One skilled in the art will appreciate, based on a review of this disclosure, that the implementation of the system600may be achieved via the use of hardware, software, firmware, or any combination thereof.

Referring now toFIG. 7, a flow chart of a method700for processing/servicing a blade is shown. The method700may be at least partially executed by one or more systems or components, such as for example the system600ofFIG. 6.

In block704, a first image of a blade may be obtained. For example, as part of block704an image of a particular blade (potentially identified by, e.g., a serial number) may be captured. Alternatively, the image of block704may be established based on one or more specifications, blueprints, etc., associated with the blade. The image of block704may be used to establish a baseline for the blade and may be used to determine/monitor an evolution in terms of debris collection/aggregation in the blade over time.

In block708, a second image of the blade may be obtained. The image of block708may be obtained based on a maintenance/service procedure performed with respect to the blade.

In block712, the first and second images of the blade may be compared. The comparison may identify one or more regions of the blade that likely contain debris. If the comparison identifies such a region, flow may proceed to block716; otherwise, the blade may be substantially debris-free and may be restored to service on an engine.

In block716, a probe may be selected to target the region(s) identified in block712. As part of block716, one or more parameters (e.g., an insertion length, a direction of orientation of an opening) may be selected. As part of block716, the selected probe may be inserted into the blade.

In block720, a fluid source coupled to the probe may be enabled/activated to cause fluid from the fluid source to remove the debris in the region(s) identified in block712.

In block724, a third image of the blade may be obtained.

In block728, the third image may be compared to at least one of the first or second images to confirm that the debris is removed (either completely or in an amount sufficient to be considered acceptable for use on an engine). If the comparison of block728reveals that the debris is removed, flow may proceed to block732.

In block732, one or more of the first, second, or third images may be saved/stored. For example, saving the third image may be used to establish a baseline of the blade, which is to say that the third image of block724may correspond to the first image of block704in a future execution of the method700.

The method700is illustrative. In some embodiments, additional blocks/operations may be included. In some embodiments, one or more of the blocks (or one or more portions thereof) may be optional. In some embodiments, the blocks may execute in an order or sequence that is different from what is shown inFIG. 7.

In some embodiments, the comparisons of the images described above in connection withFIG. 7may not occur. For example, in some embodiments an image of the blade may be obtained during a maintenance/servicing procedure (e.g., corresponding to the image of block708) and that image may be examined simply to identify discernable patterns in the image that are likely representative of debris. In this respect, a comparison (e.g., block712) of that image with, e.g., a prior image (e.g., the image of block704) may not occur as the determination of whether debris is likely present in a given region may be based on the (second) image itself.

Aspects of the disclosure have been described in terms of illustrative embodiments thereof. Numerous other embodiments, modifications, and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure. For example, one of ordinary skill in the art will appreciate that the steps described in conjunction with the illustrative figures may be performed in other than the recited order, and that one or more steps illustrated may be optional in accordance with aspects of the disclosure. One or more features described in connection with a first embodiment may be combined with one or more features of one or more additional embodiments.