Patent Application
20250116226
The present disclosure relates to gas turbine engines in general and to gas turbine engine including entrained particle separation device in particular.
Debris entrained in air that is ingested into the core of a turbine engine negatively impacts the durability of engine components such as combustors and turbines because the debris can clog cooling passages and build up on impingement surfaces, thereby reducing the efficiency of heat conduction. Air contamination primarily occurs at takeoff and landing due to the higher concentration of dirt particles near the ground. Once the dirt reaches the hottest part of the engine, in the combustor and HPT, it tends to be a very small particle size because it has passed through the compressor. What is needed is an improved system for removing entrained articles from air passing within a turbine engine.
According to an aspect of the present disclosure, a turbine engine having an axial centerline is provided that includes a compressor section, a combustor section, an outer casing, an inner diffuser case, a turbine section, a particle separator, and a particle agglomerator. The outer casing is disposed radially outside of and spaced apart from an annular combustor. A diffuser outer diameter (OD) flow path is disposed radially between the outer casing and the outer combustor wall. The inner diffuser case is disposed radially inside of and spaced apart from the annular combustor. A diffuser inner diameter (ID) flow path is disposed radially between the inner combustor wall and the inner diffuser case. The particle agglomerator is configured to produce acoustic signals that causes agglomeration of particles entrained in an air flow within the turbine engine.
In any of the aspects or embodiments described above and herein, the particle agglomerator may be disposed to act on the air flow upstream of the particle separator within the turbine engine.
In any of the aspects or embodiments described above and herein, the particle agglomerator may include a first particle agglomerator disposed in the diffuser OD flow path, and a second particle agglomerator disposed in the diffuser ID flow path.
In any of the aspects or embodiments described above and herein, the particle agglomerator may include a plurality of first particle agglomerators disposed in the diffuser OD flow path, and a plurality of second particle agglomerators disposed in the diffuser ID flow path.
In any of the aspects or embodiments described above and herein, the plurality of first particle agglomerators may be axially spaced apart from one another within the diffuser OD flow path, and the plurality of second said particle agglomerators may be axially spaced apart from one another within the diffuser ID flow path.
In any of the aspects or embodiments described above and herein, the particle agglomerator may include a first particle agglomerator and a second particle agglomerator, and the first particle agglomerator may be configured to produce first acoustic signals and the second particle agglomerator may be configured to produce second acoustic signals, and the first acoustic signals are different than the second acoustic signals.
In any of the aspects or embodiments described above and herein, the particle separator may be disposed in the diffuser OD flow path or the diffuser ID flow path.
In any of the aspects or embodiments described above and herein, the particle agglomerator may be controllable between an on mode wherein the particle agglomerator produces acoustic signals, and an off mode wherein the particle agglomerator does not produce acoustic signals.
In any of the aspects or embodiments described above and herein, the particle agglomerator may be controllable to produce acoustic signals at a first frequency and to produce acoustic signals at a second frequency, the second frequency different than the first frequency.
In any of the aspects or embodiments described above and herein, the turbine engine may include a fluid injector configured to inject fluid into the air flow.
According to an aspect of the present disclosure, a method of removing particles entrained within an air flow passing through a turbine engine is provided. The turbine engine includes a combustor section having an annular combustor, a diffuser outer diameter (OD) flow path, and a diffuser inner diameter (ID) flow path. The method includes: using a particle agglomerator to subject particles entrained within an air flow passing through a turbine engine to acoustic signals, the acoustics signal configured to cause at least some of the entrained particles to agglomerate with one another; and using at least one particle separator to remove the agglomerated particles.
In any of the aspects or embodiments described above and herein, wherein the method may include the step of controlling the particle agglomerator to be in an on mode during aircraft takeoff and during aircraft landing, and controlling the particle agglomerator to be in an off mode during aircraft cruise.
In any of the aspects or embodiments described above and herein, the method may include the step of injecting a fluid into the air flow upstream of the at least one particle agglomerator.
The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. For example, aspects and/or embodiments of the present disclosure may include any one or more of the individual features or elements disclosed above and/or below alone or in any combination thereof. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting.
As stated above, debris (e.g., particles) entrained in air that is ingested into the core of a turbine engine 20 may negatively impact the durability of components within the combustor section 32 and the turbine section 34 because the debris can clog cooling passages and build upon impingement surfaces, thereby reducing the efficiency of heat conduction. Entrained particles that reach the hot sections of the turbine engine 20 tend to have a very small particle sizes because they have passed through the compressor section 30.
The present disclosure utilizes particle separators 58 disposed within the diffuser ID flow path 64 and/or the diffuser OD flow path 62 to separate debris from the air ingested into the core of the turbine engine 20. In some embodiments, a present disclosure particle separator 58 may be configured to centrifugally separate particles entrained within the air entering the combustor section 32. An example of such a particle separator 58 is shown in
The cavity member 100 extends along the central axis 108 between a forward end 116 and an aft end 118. The forward end 116 of the cavity member 100 may expand in diameter forward to aft (e.g., a tapered configuration as shown, or an arcuate configuration such as parti-spherical, parti-ellipsoidal, or the like) but is not limited to any particular configuration. The cavity member 100 is hollow (e.g., having an interior region 120) and the aft end 118 is open (forming a second airflow exit from the particle separator 58). The cavity member 100 is configured (e.g., via perforations 122 or the like) to receive airflow (shown as arrows 124) passing through the helical passage 126 as will be detailed herein. The cavity member 100 shown in
Particles entrained in air very often possess a static charge (positive or negative charge). The aforesaid static charge may result from contact between the particles and other objects; e.g., other particles and/or surfaces. The compressing work performed on the air by the compressor section 30 upstream of the combustor section 32 may increase the probability of entrained particles possessing a static charge. The compressing work may also decrease the percentage of particles having a relatively larger diameter and increase the percentage of particles having a relatively smaller diameter. In some embodiments, the particle separator 58 may be configured such that a portion of the particle separator 58 possesses an electrostatic charge continuously or intermittently. The present disclosure is not limited to any particular means for producing an electrostatic charge on a portion of the particle separator 58. The electrostatically charged portion of the particle separator 58 may facilitate particle separation by attracting the particles in a predetermined direction thereby increasing the concentration of particles within a first portion of the airflow traveling within the separator and decreasing the concentration of particles within a second portion of the airflow traveling within the separator. For example, an embodiment of the present disclosure particle separator 58 may be configured such that the housing exterior wall 104 possesses an electrostatic charge (e.g., a positive electrical charge) that is opposite the static charge (e.g., a negative electrical charge) possessed by entrained particles. The potential difference between the aforesaid charges motivates the particles toward the housing exterior wall 104. The particle separator 58 housing is a non-limiting example of a portion of the separator 58 that may possess an electrostatic charge. The present disclosure is not limited to any particular mechanism for producing the electrostatic charge; e.g., an energy source that provides an electrical bias, or an electromagnetic field source, or the like.
As stated above, embodiments of the present disclosure may utilize one or more particle agglomerators 59 disposed upstream of the particle separators 58. A present disclosure particle agglomerator 59 may be configured to use acoustic signals to cause particles entrained within the air flow upstream of the particle separators 58 to agglomerate. Entrained particles that combine with one another (i.e., “agglomerate”) may increase in mass and/or in size. Agglomerated entrained particles are understood to facilitate particle separation within an air flow; e.g., agglomerated particles are more susceptible to centrifugal separation due to their increased mass and/or size. A present disclosure particle agglomerator 59 may be configured to produce acoustic signals that are not present within the air flow path environment (e.g., at a frequency not normally present during operation of the engine at the time of agglomeration), or a present disclosure particle agglomerator 59 may be configured to modify (e.g., amplify, filter, separate, and the like) acoustic signals that are normally present within the air flow path environment during operation into a form that acoustically produces particle agglomeration, or some combination thereof. Present disclosure particle agglomerators 59 may be configured to utilize various mechanisms to produce particle interactions (e.g., orthokinetic interactions, hydrodynamic interactions, and the like) that produce the desired particle agglomerations. The characteristics of the acoustic signals that cause particle agglomeration may be selected based on the characteristics (e.g., mass, size, and the like) of particles to be agglomerated. For example, the frequency and intensity of the acoustic signals may be selected based on the propensity of those acoustic signals to cause agglomeration of target entrained particles; e.g., particular size particles, and the like. In general, lower frequencies in the human audible range (i.e., about 20 Hz to 20,000 Hz) are understood to be effective for the agglomeration of particles in the micron and sub-micron ranges. The present disclosure is not, however, limited to using acoustic signals in the frequency range of 20-20,000 Hz. It is currently understood that acoustic signals above 20,000 Hz (e.g., up to 40,000 Hz) may be effective to cause agglomeration of particles entrained within a turbine engine gas path. Hence, the present disclosure contemplates that acoustic signals at any frequency that is useful to cause particle agglomeration of particles entrained within a gas path of a turbine engine 20 may be used. The rate at which particle agglomerations may occur may also be a function of the intensity of the acoustic signals. In some applications, agglomeration may benefit from using higher intensity (e.g., higher decibels or “dBs”) acoustic signals. The residence time (i.e., the amount of time the particles are exposed to the acoustic field) may be selected as appropriate for the particles to be agglomerated. The acoustic signals utilized by the present disclosure particle agglomerators 59 are preferably benign to the operation of the turbine engine 20. In some embodiments, a present disclosure embodiment that utilizes a particle agglomerator 59 may also include mechanisms for mitigating undesirable effects that may be produced by the aforesaid acoustic signals. For example, the present disclosure may include structure and/or controls configured to actively (e.g., noise cancellation) or passively (e.g., acoustic insulation) mitigate acoustic signal propagation outside of the zone in which particle agglomeration is desired.
As described herein, present disclosure particle agglomerators 59 are disposed upstream of the particle separators 58. It is understood that disposing particle agglomerators 59 within the diffuser OD flow path 62 and the diffuser ID flow path 64 upstream of the particle separators 58 (e.g., as shown diagrammatically in
In those embodiments that include more than one particle agglomerator 59, all of the agglomerators 59 may be identical (e.g., each producing the same acoustic signals (or modifying environmental signal in the same manner), or the plurality of particle agglomerators 59 may include differently configured particle agglomerators 59; e.g., one or more first particle agglomerators 59 having a first configuration (e.g., producing acoustic signals at a first frequency, or first intensity, or any combination thereof) and one or more second particle agglomerators 59 having a second configuration (e.g., producing acoustic signals at a second frequency, or second intensity, or any combination thereof), wherein the first acoustics signal are different from the second acoustic signals. Using different acoustic signal at different positions may provide several benefits; e.g., different frequencies for agglomerating different size entrained particles, and the like.
As diagrammatically shown in
In some embodiments, a present disclosure particle agglomerator 59 may be configured in a fixed configuration that is not adjustable; e.g., a device that only produces acoustic signals having particular characteristics (e.g., frequency, intensity, and the like). In some embodiments, a present disclosure particle agglomerator 59 may be configured as a controllable device that can be controlled to produce selectively different acoustic signals; e.g., controllable to produce first acoustic signals at a first frequency, first intensity, and the like, and controllable to produce second acoustic signals at a second frequency, second intensity, and the like.
In those embodiments that include controllable particle agglomerators 59, the aforesaid agglomerators may be in communication with a controller 142. The controller 142 may be configured to control and/or receive signals therefrom to perform the functions described herein. The controller 142 may include any type of computing device, computational circuit, processor(s), CPU, computer, or the like capable of executing a series of instructions that are stored in memory. The instructions may include an operating system, and/or executable software modules such as program files, system data, buffers, drivers, utilities, and the like. The executable instructions may apply to any functionality described herein to enable the system to accomplish the same algorithmically and/or coordination of system components. The controller 142 includes or is in communication with one or more memory devices. The present disclosure is not limited to any particular type of memory device, and the memory device may store instructions and/or data in a non-transitory manner. Examples of memory devices that may be used include read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and/or any device that stores digital information. Communications between the controller 142 and other system components may be via a hardwire connection or via a wireless connection. In those embodiments that include controllable particle agglomerators 59, the present disclosure system may include sensors 61 (see
In some embodiments, the present disclosure may be configured to introduce a fluid (either a liquid or a gas, or some combination thereof) into the air flow path upstream of the particle agglomerators 59; e.g., via one or more fluid injectors 144 (see
In the operation of a turbine engine 20 (e.g., see
Entrained particulate matter can be particularly problematic in the combustor section 32 and the turbine section 34 where component cooling is required. In many applications, engine cooling schemes use relatively small diameter cooling apertures to produce impingement cooling and/or to establish cooling air boundary layer flow adjacent to a component surface, or the like. In these instances, the diameter of the cooling aperture may be directly related to the desired cooling effect. In some instances, the diameter of the cooling aperture is limited by the potential for particulate fouling; i.e., a minimum diameter of a cooling aperture is selected to avoid fouling and consequent cooling deficit.
The present disclosure provides a novel and unobvious system and method for removing entrained particles upstream of the engine components where particulate fouling is problematic; i.e., engine hot section components that utilize cooling air.
Referring to
In those embodiments of the present disclosure wherein a portion of the particle separator 58 is configured to possess an electrostatic charge, the particulate matter entrained within the dirty air enters the helical passage 126 disposed within the interior cavity 106 of the housing 96. As the dirty air passes through the helical passage 126, the electrostatically charged portion of the particle separator 58 (e.g., the housing exterior wall 104) attracts the oppositely charged entrained particles and provides a motive force that moves the entrained particles radially outward (i.e., toward the separator exterior wall 104). As a result, the concentration of particles within a portion of the air adjacent the exterior wall 104 will increase and the concentration of particles within a portion of the air adjacent the cavity member 100 will decrease. The portion of the air adjacent the cavity member 100 will enter the cavity member 100 and will travel axially therethrough until it exits the particle separator 58. The portion of the air adjacent the exterior wall 104 will continue to travel through the helical passage 126 until it reaches the aft exhaust passage 102. As stated herein, in some present disclosure embodiments the electrostatically charged portion of the particle separator 58 may be cycled between an “on mode” wherein the portion is electrostatically charged and an “off mode” wherein the portion is not electrostatically charged to prevent particle accumulation on the charged portion.
The “dirty air” entering the aft exhaust passage 102 is directed into the combustion chamber 88 via a relatively large diameter aperture; e.g., a dilution aperture 94. As stated above, in some embodiments a particle separator 58 aft exhaust passage 102 may be directly engaged with an aperture (e.g., a dilution aperture 94—see
The portion of the air that enters the cavity member 100 (hereinafter referred to as “clean air”) is understood to contain substantially less particulate matter than the dirty air. The clean air exiting the cavity member 100 may be used for a variety of different purposes. For example, as detailed above it is known to use cooling air to cool a combustor wall assembly 78, 80. Referring to
Clean air exiting the particle separators 58 within the diffuser OD flow path 62 may be used to cool the HPT components including, but not limited to, the first HPT stator vane stage 66, the first HPT rotor BOAS 70, the second HPT stator vane stage 72, the second HPT rotor BOAS 76, and the like (see
Embodiments of the present disclosure particle separators 58 that are configured to separate entrained particles both centrifugally and electrostatically are understood to provide a substantial improvement in particle separation. As stated above, the work performed on the air passing through the compressor is understood to increase the percentage of the entrained particles having a relatively smaller diameter and decrease the percentage of entrained particles having a relatively larger diameter. The present disclosure particle separator 58 embodiments that employ a combination of centrifugal and electrostatic separation is understood to be effective at removing both larger entrained particles (more susceptible to centrifugal forces) and smaller particles (less susceptible to centrifugal forces, but more apt to have a particular electrostatic charge). It is understood that not all entrained particles will have the same electrostatic charge. It is understood further that “small” particles (i.e., those having a diameter/hydraulic diameter less than fifty microns-50 μm) typically possess a negative charge and “large” particles (i.e., those having a diameter/hydraulic diameter greater than fifty microns-50 μm) typically possess a positive charge. Present disclosure particle separator 58 embodiments that include electrostatic separation may be configured to have a portion of the particle separator 58 (e.g., the housing exterior wall 104) electrostatically charged (e.g., a positive electrostatic charge) to attract smaller entrained particles. In this manner, embodiments of the present disclosure are understood to effectively remove entrained particles having a range of diameters in the environment downstream of the compressor section 30, thereby producing “clean air” immediately upstream of hot section cooling applications that are susceptible of particulate fouling. In some applications, the present disclosure particle separators 58 may make it possible to utilize decreased diameter cooling holes (otherwise not practical due to particulate fouling potential) that may provide cooling benefits.
In those present disclosure embodiments that include one or more particle agglomerators 59, the particle agglomerators 59 may be operated continuously, intermittently, or during specific flight portions. For example, as indicated herein, air contamination primarily occurs at takeoff and landing due to the higher concentration of dirt particles near the ground. In view thereof, the present disclosure system may be controlled to operate the particle agglomerators 59 during those portions of a flight potentially subject to heavier particle ingestion (e.g., takeoff and landing) and to not operate the particle agglomerators 59 during those portions of a flight above a predetermined altitude; e.g., above 2000 feet above ground level, above 1000 meters above ground level, etc., and/or during a cruise portion of a flight where the air is substantially “cleaner”. The particle agglomerators 59 may be operated in any portion of a flight, however. The particle agglomerators 59 may be described as being in an “on mode” when they are controlled to produce the acoustic signals and in an “off mode” when they do not produce acoustic signals. Within the present disclosure, the particle agglomerators 59 may be operated to increase the size of entrained particles and thereby facilitate separation of those particles; e.g., via centrifugal separation due to their increased mass and/or size. In those embodiments wherein the particle agglomerators 59 are non-adjustable, the characteristics of the acoustic signals may be based on empirical data indicating the propensity of certain diameter particles to be entrained within the air flow. Hence, the characteristics of the acoustic signals may be chosen to target certain diameter entrained particles. In those embodiments that include a plurality of particle agglomerators 59, including differently configured particle agglomerators 59, some agglomerators 59 may be configured to cause agglomeration of particles in a first range of diameters, and other agglomerators 59 may be configured to cause agglomeration of particles in a second range of diameters different than the first range. The agglomerated particles may be subsequently processed in the manner described herein; e.g., drawn into a particle separator and exhausted into the combustor combustion chamber 88, thereby removing the entrained particles from air flow (often referred to as “secondary air flow”) that may be used within the combustor 35 or within turbine section 34 for cooling purposes as described herein. Hence, the particle agglomerators 59 are understood to enhance the ability of the present disclosure system to “clean” the air flow of entrained particles, even beyond the capability of the particle separators 58 alone.
It should be noted that the particle agglomerators 59 may be used with a variety of different particle separators 58 and therefore the present disclosure particle agglomerators 59 are not limited to use with the particle separators 58 described herein. The particle separators 58 described herein are a non-limiting example of a particle separators 58 that may be used with the particle agglomerators 59.
While the principles of the disclosure have been described above in connection with specific apparatuses and methods, it is to be clearly understood that this description is made only by way of example and not as limitation on the scope of the disclosure. Specific details are given in the above description to provide a thorough understanding of the embodiments. However, it is understood that the embodiments may be practiced without these specific details.
It is noted that the embodiments may be described as a process which is depicted as a flowchart, a flow diagram, a block diagram, etc. Although any one of these structures may describe the operations as a sequential process, many of the operations can be performed in parallel or concurrently. In addition, the order of the operations may be rearranged. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.
The singular forms “a,” “an,” and “the” refer to one or more than one, unless the context clearly dictates otherwise. For example, the term “comprising a specimen” includes single or plural specimens and is considered equivalent to the phrase “comprising at least one specimen.” The term “or” refers to a single element of stated alternative elements or a combination of two or more elements unless the context clearly indicates otherwise. As used herein, “comprises” means “includes.” Thus, “comprising A or B,” means “including A or B, or A and B,” without excluding additional elements.
It is noted that various connections are set forth between elements in the present description and drawings (the contents of which are included in this disclosure 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. Any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option.
No element, component, or method step in the present disclosure is intended to be dedicated to the public regardless of whether the element, component, or method step is explicitly recited in the claims. No claim element herein is to be construed under the provisions of 35 U.S.C. 112(f) unless the element is expressly recited using the phrase “means for.” As used herein, the terms “comprise”, “comprising”, or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While various inventive aspects, concepts and features of the disclosures may be described and illustrated herein as embodied in combination in the exemplary embodiments, these various aspects, concepts, and features may be used in many alternative embodiments, either individually or in various combinations and sub-combinations thereof. Unless expressly excluded herein all such combinations and sub-combinations are intended to be within the scope of the present application. Still further, while various alternative embodiments as to the various aspects, concepts, and features of the disclosures—such as alternative materials, structures, configurations, methods, devices, and components, and so on—may be described herein, such descriptions are not intended to be a complete or exhaustive list of available alternative embodiments, whether presently known or later developed. Those skilled in the art may readily adopt one or more of the inventive aspects, concepts, or features into additional embodiments and uses within the scope of the present application even if such embodiments are not expressly disclosed herein. For example, in the exemplary embodiments described above within the Detailed Description portion of the present specification, elements may be described as individual units and shown as independent of one another to facilitate the description. In alternative embodiments, such elements may be configured as combined elements. It is further noted that various method or process steps for embodiments of the present disclosure are described herein. The description may present method and/or process steps as a particular sequence. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible.
