Turbine engine with balance chamber

Abstract

A turbine engine has a drive shaft rotatable about an axis, a multi-stage compressor, a turbine section, a thrust bearing, and a balance cavity. The thrust bearing is disposed between the drive shaft and at least a portion of the multi-stage compressor section and rotatably supports the drive shaft. During operation of the turbine engine, a first axial force is exerted by the drive shaft to the thrust bearing, and a second axial force is exerted by the balance cavity to the thrust bearing in a direction opposite the first axial force.

Description

Technical Field

[0001] This topic generally relates to turbine engines, and more specifically, to balance chambers used in turbine engines. Background Technology

[0002] A turbine engine (and particularly a gas turbine engine) is a rotary engine that extracts energy from a flow of working air and provides thrust in an aircraft implementation. This flow of working air passes sequentially through a compressor section (where working air is compressed), a combustor section (where fuel is added to the working air and ignited), and a turbine section (where the working air is expanded and work is extracted from the working air to drive the compressor section and other systems). A drive shaft can operatively connect the turbine section, compressor section, and fan section such that rotation of the turbine section drives the compressor section and fan section.

[0003] At least one thrust bearing may be disposed between the turbine section and the drive shaft, and serves to rotatably support the drive shaft and accommodate the longitudinal axial forces generated on the drive shaft by the thrust from the engine. A balancing chamber within the turbine engine can provide a force opposite to the thrust, thereby reducing the overall magnitude of the axial forces acting on the thrust bearing. The balancing chamber receives pressurized air from the compressor section, where the pressure is opposite to the thrust. Attached Figure Description

[0004] The complete and feasible disclosure of this disclosure, including its best mode, is set forth in the specification with reference to the accompanying drawings, for those skilled in the art, wherein:

[0005] Figure 1 This is a schematic cross-sectional view of a turbine engine according to an exemplary embodiment of the present disclosure, the turbine engine including a multi-stage compressor section.

[0006] Figure 2 It is applicable Figure 1 A schematic cross-sectional view of a multi-stage compressor section within a turbine engine, the multi-stage compressor section having a thrust bearing that rotatably supports a drive shaft, and a balance chamber located at least partially axially forward of the thrust bearing. Detailed Implementation

[0007] The aspects disclosed herein relate to a turbine engine comprising a multi-stage compressor section and a turbine section arranged in an axial flow configuration. The multi-stage compressor section may include at least two rotating blades axially adjacent to corresponding stationary blades. The stationary blades and the axially adjacent downstream rotating blades may together define a stage. Therefore, as used herein, the term "multi-stage compressor section" may refer to a compressor section comprising two or more stages. A drive shaft may rotatably connect the turbine section to the multi-stage compressor section. The drive shaft may rotate about an axis. A thrust bearing may be radially disposed relative to the axis between the drive shaft and a portion of the multi-stage compressor section. A balancing chamber may be fluidly connected to a downstream portion of the multi-stage compressor section and includes fluid from the downstream portion. During operation of the turbine engine, the turbine engine may rotate the drive shaft, which in turn rotates the multi-stage compressor section. The total thrust at the turbine end may apply a forward and backward axial force relative to the axis on the drive shaft, the forward and backward axial forces ultimately being transmitted to the thrust bearing. The balancing chamber may apply a backward and forward axial force relative to the axis on the thrust bearing. The front-rear force applied by the balancing cavity can counteract and offset the front-rear forces on the thrust bearing.

[0008] As described herein, a balancing cavity can counteract or balance axial forces on a thrust bearing that rotatably supports a portion of the drive shaft axially forward of the turbine section. Under certain operating conditions, turbine engines experience relatively high axial loads. As described herein, the balancing cavity serves to ensure that the thrust bearing can continue to rotatably support the drive shaft without failure under all operating conditions of the turbine engine. For illustrative purposes, this disclosure will be described with respect to a balancing cavity disposed within a turbine engine, wherein the balancing cavity is located near a portion of a multi-stage compressor section. However, it will be understood that aspects of this disclosure described herein are not limited thereto and can have general applicability in other engines. For example, this disclosure can be applied to balancing cavities in other engines or vehicles and can provide benefits in industrial, commercial, and residential applications.

[0009] As used herein, the term "upstream" refers to the direction opposite to the direction of fluid flow, while the term "downstream" refers to the direction in the same direction as the fluid flow. The terms "front" or "in front" indicate what is in front of something, and "back" or "behind" indicate what is behind something. For example, when used in relation to fluid flow, "front" or "in front" can indicate upstream, and "back" or "behind" can indicate downstream.

[0010] Furthermore, as used herein, the term "radial" or "radially" refers to a direction away from a common center. For example, in the overall context of a turbine engine, radial refers to the direction of a ray extending between the engine's central longitudinal axis and the engine's outer perimeter. Additionally, as used herein, the term "group" or a "set" of elements can refer to any number of elements, including only one element.

[0011] Furthermore, as used herein, the term "fluid" or its iterations may refer to any suitable fluid within a gas turbine engine, at least a portion of which is exposed to, for example, but not limited to, combustion gases, ambient air, pressurized gas flow, operating gas flow, or any combination thereof. It is further envisioned that the gas turbine engine may be other suitable turbine engines, such as, but not limited to, steam turbine engines or supercritical carbon dioxide turbine engines. As a non-limiting example, the term "fluid" may refer to steam in a steam turbine engine or carbon dioxide in a supercritical carbon dioxide turbine engine.

[0012] All directional references (e.g., radial, axial, proximal, distal, up, down, upward, downward, left, right, lateral, front, rear, top, bottom, above, below, vertical, horizontal, clockwise, counterclockwise, upstream, downstream, forward, backward, etc.) are used for identification purposes only to aid the reader's understanding of this disclosure and do not impose limitations, particularly regarding the location, orientation, or purpose of aspects of this disclosure described herein. Unless otherwise stated, connecting references (e.g., attachment, connection, fixation, fastening, joining, and engagement) are to be interpreted broadly and may include intermediate members between sets of elements and relative movement between elements. Therefore, connecting references do not necessarily imply that two elements are directly connected and have a fixed relationship with each other. Exemplary drawings are for illustrative purposes only, and the dimensions, positions, order, and relative sizes reflected in the accompanying drawings may vary.

[0013] Figure 1 This is a schematic cross-sectional view of a turbine engine 10 for an aircraft. The turbine engine 10 has a generally longitudinally extending axis or engine centerline 12 extending from the front 14 to the rear 16. The turbine engine 10 includes the following downstream sequential flow relationships: a fan section 18, which includes a fan 20; a compressor section 22, which includes a supercharger or low-pressure (LP) compressor 24 and a high-pressure (HP) compressor 26; a combustion section 28, which includes a combustor 30; a turbine section 32, which includes an HP turbine 34 and an LP turbine 36; and an exhaust section 38.

[0014] Fan section 18 includes a fan housing 40 surrounding fan 20. Fan 20 includes a plurality of fan blades 42 arranged radially around engine centerline 12. HP compressor 26, combustor 30 and HP turbine 34 form engine core 44 of turbine engine 10, which generates combustion gases. Engine core 44 is surrounded by core housing 46, which can be coupled to fan housing 40.

[0015] Drive shaft 51 is rotatably connected to compressor section 22, and fan section 18 is operatively connected to turbine section 32. Rotation of turbine section 32 transmits rotational force to drive shaft 51, which in turn transmits it to at least one of compressor section 22 or fan section 18 to drive compressor section 22 or fan section 18. Drive shaft 51 is rotatable about an axis. In the illustrated turbine engine 10, drive shaft 51 is rotatable about engine centerline 12.

[0016] Drive shaft 51 may include a separate spool. As a non-limiting example, drive shaft 51 may include an HP shaft or spool 48 coaxially arranged about the engine centerline 12 of the turbine engine 10, drivingly connecting the HP turbine 34 to the HP compressor 26. As a non-limiting example, drive shaft 51 may include an LP shaft or spool 50 coaxially arranged about the engine centerline 12 of the turbine engine 10 within a larger diameter annular HP spool 48, drivingly connecting the LP turbine 36 to the LP compressor 24 and the fan 20. Spools 48 and 50 may together define drive shaft 51. Spools 48 and 50 may be rotatable about the engine centerline 12 and coupled to a plurality of rotatable elements that may collectively define a rotor.

[0017] LP compressor 24 and HP compressor 26 each include multiple compressor stages 52 and 54, respectively, in which a set of compressor blades 56 and 58 rotate relative to a corresponding set of static compressor impeller blades 60 and 62 (also referred to as nozzles) to compress or pressurize the fluid flow passing through the stage. In a single compressor stage 52 or 54, the multiple compressor blades 56 and 58 may be arranged in a ring and may extend radially outward from the blade platform relative to the engine centerline 12 to the blade tips, while the corresponding static compressor impeller blades 60 and 62 are positioned upstream of and adjacent to the rotating blades 56 and 58. It is worth noting that... Figure 1 The number of blades, impellers, and compressor stages shown is selected for illustrative purposes only, and other numbers are also possible.

[0018] The blades 56 and 58 for the first stage of the compressor can be mounted on a disc 61, which is mounted on a corresponding one of the HP spool 48 and the LP spool 50, with each stage having its own disc 61. The impeller blades 60 and 62 for the first stage of the compressor can be mounted circumferentially to the core housing 46.

[0019] HP turbine 34 and LP turbine 36 each comprise multiple turbine stages 64 and 66, respectively, in which a set of turbine blades 68 and 70 rotate relative to a corresponding set of static turbine blades 72 and 74 (also referred to as nozzles) to extract energy from the fluid flow passing through the stage. In a single turbine stage 64 and 66, the multiple turbine blades 68 and 70 may be arranged in a ring and may extend radially outward from the blade platform relative to the engine centerline 12 to the blade tips, while the corresponding static turbine blades 72 and 74 are positioned upstream of and adjacent to the rotating turbine blades 68 and 70. It is worth noting that... Figure 1 The number of blades, impellers, and turbine stages shown is selected for illustrative purposes only; other numbers are also possible.

[0020] Turbine blades 68 and 70 for the first stage of the turbine can be mounted to disk 71, which is mounted to a corresponding one of HP spool 48 and LP spool 50, with each stage having a dedicated disk 71. Blades 72 and 74 for the first stage of the compressor can be mounted circumferentially to the core housing 46.

[0021] As a complement to the rotor section, the stationary parts of the turbine engine 10 (e.g., the static blades 60, 62, 72, 74 in the compressor section 22 and the turbine section 32) are also referred to individually or collectively as the stator 63. Therefore, the stator 63 can refer to the combination of non-rotating elements throughout the turbine engine 10.

[0022] A set of thrust bearings rotatably supports the drive shaft 51. As a non-limiting example, this set of thrust bearings may include at least a front thrust bearing 90 and a rear thrust bearing 92. The front thrust bearing 90 may be axially positioned forward from the rear thrust bearing 92 relative to the engine centerline 12. The front thrust bearing 90 may be radially disposed between the drive shaft 51 and the compressor section 22 relative to the engine centerline 12. The rear thrust bearing 92 may be radially disposed between the drive shaft 51 and the turbine section 32 relative to the engine centerline 12.

[0023] In operation, the airflow leaving fan section 18 is split, with a portion directed to LP compressor 24. LP compressor 24 then supplies pressurized airflow 76 to HP compressor 26, which further pressurizes the air. The pressurized airflow 76 from HP compressor 26 mixes with fuel in combustor 30 and ignites, generating combustion gases. HP turbine 34 extracts some work from these gases and drives HP compressor 26 via drive shaft 51. The combustion gases are discharged to LP turbine 36, which extracts additional work to drive LP compressor 24, and the exhaust is ultimately discharged from turbine engine 10 via exhaust section 38. The drive of LP turbine 36 drives LP spool 50 to rotate fan 20 and LP compressor 24.

[0024] A portion of the pressurized gas flow 76 can be drawn from the compressor section 22 as bleed air 77. Bleed air 77 can be drawn from the pressurized gas flow 76 and supplied to engine components requiring cooling. The temperature of the pressurized gas flow 76 entering the combustor 30 is significantly increased. Therefore, cooling provided by bleed air 77 is necessary for operating these engine components in elevated temperature environments.

[0025] The remaining portion of the airflow leaving the fan section, bypass airflow 78, bypasses the LP compressor 24 and engine core 44, and exits the turbine engine 10 via a stationary blade row (more specifically, the outlet guide blade assembly 80, comprising multiple airfoil guide blades 82) at the fan exhaust side 84. More specifically, a circumferential row of radially extending airfoil guide blades 82 is used adjacent to the fan section 18 to exert some directional control on the bypass airflow 78.

[0026] Some of the air supplied by fan 20 can bypass engine core 44 and be used to cool parts of turbine engine 10, especially hot parts, and / or to cool other aspects of the aircraft or power other aspects of the aircraft. In the case of a turbine engine, the hot parts of the engine are typically downstream of combustor 30, especially turbine section 32, with HP turbine 34 being the hottest part because it is located directly downstream of combustion section 28. Other sources of cooling fluid may be, but are not limited to, fluid discharged from LP compressor 24 or HP compressor 26.

[0027] Figure 2 It is suitable for use as Figure 1A schematic cross-sectional view of the multistage compressor section 100 of the compressor section 22 of the turbine engine 10. The multistage compressor section 100 is rotatably coupled to a drive shaft 102, which is rotatably coupled to a turbine section (e.g., turbine section 32) downstream of the multistage compressor section 100. The drive shaft 102 is rotatable about an axis 104. A thrust bearing 106 rotatably supports the drive shaft 102 and is located between a portion of the drive shaft 102 and a portion of the multistage compressor section 100. As a non-limiting example, the thrust bearing 106 may be located between a portion of the drive shaft 102 and a static portion of the multistage compressor section 100. A balancing chamber 108 may be located at least partially axially forward of the thrust bearing 106 relative to the axis 104. The balancing chamber 108 may be fluidly coupled to pressurized fluid from a portion of the multistage compressor section 100. The balancing cavity 108 can be operatively coupled to the thrust bearing 106 (e.g., the walls of the balancing cavity 108 can be operatively coupled to the thrust bearing 106). During operation of the turbine engine, thrust can be generated, which in turn applies a longitudinal axial force to the drive shaft 102. The longitudinal axial force can ultimately be transmitted to the thrust bearing 106 to define a first axial force 110. The balancing cavity 108 can apply a rear-forward axial force to the thrust bearing 106 relative to the axis 104. As a non-limiting example, the balancing cavity 108 can apply a second axial force 112 to the thrust bearing 106, which counteracts, opposes, or otherwise balances the first axial force 110. It is contemplated that the first axial force 110 can be greater than the second axial force 112, such that the balancing cavity 108 only reduces the total axial force experienced across the thrust bearing. Alternatively, the first axial force 110 can be equal to but opposite in magnitude to the second axial force 112, such that the thrust bearing remains axially balanced.

[0028] Thrust bearing 106 may be disposed between a portion of drive shaft 102 and a corresponding portion of multistage compressor section 100. As a non-limiting example, thrust bearing 106 may be disposed between a portion of drive shaft 102 and stationary component 101 of multistage compressor section 100. Thrust bearing 106 may extend radially between drive shaft 102 and at least a portion of multistage compressor section 100. Thrust bearing 106 may be any suitable bearing, such as, but not limited to, roller bearings, ball bearings, double ball bearings, tapered roller bearings, foil / gas bearings, journal bearings, spherical bearings, or any combination thereof.

[0029] The multistage compressor section 100 may include an LP compressor 114 and an HP compressor 116 axially disposed downstream of the LP compressor 114 relative to axis 104. Figure 1 Similar to the LP compressor 24, the LP compressor 114 may include a set of stationary LP compressor blades 117 and a set of rotating LP compressor blades 118 rotatably coupled to the drive shaft 102. Figure 1 Similar to the HP compressor 26, the HP compressor 116 may include a set of stationary HP compressor blades 120 and a set of rotating HP compressor blades 122 rotatably connected to the drive shaft 102. Each rotating LP compressor blade 118 and rotating HP compressor blade 122 may be axially positioned downstream of the corresponding stationary LP compressor blade 117 or stationary HP compressor blade 120 relative to the axis 104, and define a corresponding stage of the multi-stage compressor section 100.

[0030] The turbocharger section 124 may be defined by a downstream stage of the LP compressor 114. As a non-limiting example, the turbocharger section 124 may be the furthest axial downstream stage of the LP compressor 114.

[0031] The balancing chamber 108 may include a first pressurized fluid defining a first fluid 160. The first fluid 160 may be dispersed throughout the balancing chamber 108 as indicated by points throughout the chamber. The balancing chamber 108 may be located radially inward relative to axis 104 from at least a portion of LP. As a non-limiting example, the balancing chamber 108 may be located radially inward relative to axis 104 from the booster section 124. The balancing chamber 108 may be disposed within any portion of the multistage compressor section 100 axially forward of the combustion section. Furthermore, the thrust bearing 106 may be located along drive shaft 102 along any suitable portion of the multistage compressor section 100 (e.g., along...). Figure 1 The balancing cavity 108 is provided with an HP spool 48 or an LP spool 50. Therefore, the balancing cavity 108 can be positioned at least partially along any portion of the drive shaft 102. As shown, the balancing cavity 108 is a single balancing cavity 108. However, it should be understood that the balancing cavity 108 can be included within a plurality of balancing cavities 108 fluidly connected to each other. As a non-limiting example, the balancing cavity 108 can be one of a group of a plurality of balancing cavities 108 that are radially, axially, or circumferentially spaced from each other relative to the axis 104.

[0032] Fan section 126 can be located upstream of multi-stage compressor section 100. (And...) Figure 1 Similar to fan section 18, fan section 126 may include at least one rotating fan blade 128. The at least one rotating fan blade 128 may be rotatably coupled to drive shaft 102. As a non-limiting example, the at least one rotating fan blade 128 may be selectively rotatably coupled to drive shaft 102, such that fan section 126 may be selectively coupled to or decoupled from drive shaft 102.

[0033] The balancing chamber 108 can be fluidly connected to the multistage compressor section 100. As a non-limiting example, the balancing chamber 108 can be fluidly connected to the HP compressor 116. The balancing chamber inlet line 130 can fluidly connect the HP compressor 116 to the balancing chamber 108. As a non-limiting example, the balancing chamber inlet line 130 can be fluidly connected along the first and fourth stages of the HP compressor 116 or between the first and fourth stages of the HP compressor 116. As a non-limiting example, the balancing chamber inlet line 130 can be fluidly connected to stage 1.5 of the HP compressor 116 (e.g., between the rotating HP compressor blades 122 and the stationary HP compressor impeller 120 in the second stage of the HP compressor 116). The balancing chamber inlet line 130 is shown as fluidly connected to the radially outer portion of the HP compressor 116 relative to axis 104. However, as shown by the balancing chamber inlet line 130 in dashed lines, the balancing chamber inlet line 130 can also, or alternatively, be fluidly connected to the radially inner portion of the HP compressor 116 relative to axis 104. As described herein, the balance chamber inlet line 130 may be either of the two balance chamber inlet lines 130 described herein. Alternatively, the balance chamber inlet line 130 may be two balance chamber inlet lines 130 fluidly connected to the radially outer portion of the HP compressor 116 relative to axis 104 and the radially inner portion of the HP compressor 116 relative to axis 104.

[0034] The balancing chamber inlet line 130 may include at least one component configured to influence the characteristics of a fluid (e.g., pressurized air from the HP compressor 116) flowing through the balancing chamber inlet line 130 and into the balancing chamber 108. As a non-limiting example, the balancing chamber inlet line 130 may include a heat exchanger 132. The heat exchanger 132 may be fluidly coupled to a coolant (e.g., ambient airflow, refrigerant, etc.) at a temperature lower than the temperature of the fluid flowing into the heat exchanger 132 within the balancing chamber inlet line 130. The heat exchanger 132 can effectively cool the fluid by transferring heat from the fluid to the coolant. As a non-limiting example, the balancing chamber inlet line 130 may include a particulate separator 134 configured to remove or otherwise filter one or more particles from the fluid flowing into the particulate separator 134.

[0035] Recovery chamber 136 may be fluidly coupled to balance chamber 108. Recovery chamber 136 may include a second pressurized fluid (e.g., pressurized air or a first pressurized fluid from balance chamber 108) defining a second fluid 162. The second fluid 162 may be dispersed throughout recovery chamber 136 as indicated by points within recovery chamber 136. Recovery chamber 136 is configured to capture or otherwise recover pressurized fluid from balance chamber 108 and deliver pressurized fluid to other parts of the turbine engine. However, it should be understood that recovery chamber 136 may be integrally formed with balance chamber 108 such that balance chamber 108 may deliver at least a portion of the pressurized fluid within balance chamber 108 to another part of turbine engine 10. Recovery chamber 136 may be located at least partially radially outward from balance chamber 108 relative to axis 104. Recovery chamber 136 may be located radially inward from turbocharger section 124 relative to axis 104. Seal 138 may be disposed between recovery chamber 136 and balancing chamber 108, and defines a fluid connection between recovery chamber 136 and balancing chamber 108. As a non-limiting example, seal 138 may be a piston seal. However, it should be understood that seal 138 may be any other suitable seal, such as, but not limited to, labyrinth seals, brush seals, non-contact seals, or any combination thereof.

[0036] The recovery chamber 136 can be fluidly connected to the discharge line 140. As shown, the discharge line 140 may include two branches. One of the two branches is fluidly connected to a diverter valve 142. The other of the two branches is fluidly connected to a portion of the multistage compressor section 100 downstream of the LP compressor 114. As a non-limiting example, the discharge line 140 can be fluidly connected to a portion of the multistage compressor section 100 downstream of the LP compressor 114 and upstream of the HP compressor 116. The diverter valve 142 can selectively fluidly connect the discharge line 140 to at least one of the turbine line 144 or the bypass line 146. As a non-limiting example, the turbine line 144 can be fluidly connected to the turbine section or the exhaust section (e.g., Figure 1 At least one of the exhaust sections 38). The bypass line 146 may be fluidly connected to a portion of the turbine engine that is directed away from or otherwise bypasses the combustion section of the turbine engine. As a non-limiting example, the turbine engine may include a secondary flow path 148 to which the bypass line 146 is fluidly connected. The secondary flow path 148 may be fluidly connected to at least one of a thrust reverser, a downstream portion of the turbine engine (e.g., a turbine section or an exhaust section), or otherwise form part of it, or otherwise fluidly connected to an external portion of the turbine engine.

[0037] Seal 138 may be positioned at a first radial distance between axis 104 and the radially inward portion of seal 138. Turbocharger section 124 may be positioned at a second radial distance between axis 104 and the radially inward portion of turbocharger section 124. The first distance may be less than the second distance. Balance chamber 108, recovery chamber 136, and seal 138 may extend circumferentially about axis 104. In other words, balance chamber 108, recovery chamber 136, and seal 138 may define a continuous annular component of the turbine engine. Alternatively, at least one of balance chamber 108, recovery chamber 136, or seal 138 may be segmented (e.g., they are one of a plurality of balance chambers 108, recovery chambers 136, or seals 138) or may not extend across the entire circumference of axis 104.

[0038] Although not shown, it should be understood that a turbine engine may include additional balancing chambers. As a non-limiting example, a turbine engine may include a turbine balancing chamber within a turbine section configured to apply opposing axial forces to a turbine thrust bearing that rotatably supports the rear portion of drive shaft 102. In other words, a turbine engine as described herein may include balancing chamber 108 as well as additional balancing chambers, such as those described in the prior art.

[0039] During operation of the turbine engine, the turbine section can apply rotational force to drive shaft 102, which in turn can rotate at least a portion of the multi-stage compressor section 100 and selectively rotate at least a portion of the fan section 126. As the fan section 126 rotates, inlet airflow 150 can be drawn into the turbine engine. Inlet airflow 150 can be defined by ambient airflow surrounding the turbine engine. The remaining portion of ambient airflow not drawn into the fan section 126 can flow around the turbine engine as external airflow 152, which can eventually merge with the exhaust fluid downstream of the exhaust section. The exhaust fluid and external airflow 152 can together define the total thrust of the turbine engine.

[0040] Once past fan section 126, inlet airflow 150 can branch in at least two directions. A first portion of inlet airflow 150 can branch into multistage compressor section 100 to define primary airflow 154 within a main flow path that extends through multistage compressor section 100, turbine section, and ultimately exhaust section. A second portion can flow into secondary flow path 148 and define secondary airflow 156. As a non-limiting example, secondary airflow 156 can be fluidly coupled to a thrust reverser, whereby it can exit the turbine engine in the opposite direction to external airflow 152. As a non-limiting example, secondary airflow 156 can be fluidly coupled to downstream portions of the turbine engine (e.g., turbine section, combustion section, or exhaust section), whereby it can cool various components within the downstream portions of the turbine engine. As a non-limiting example, secondary airflow 156 can be fluidly coupled to and merge with external airflow 152, such that secondary airflow 156 can be used to generate at least a portion of the total thrust of the turbine engine. As the primary airflow 154 flows through the LP compressor 114, the primary airflow 154 can be compressed or otherwise pressurized, defining a compressed primary airflow 158. The compressed primary airflow 158 can flow into the HP compressor 116, where the compressed primary airflow 158 is further compressed or otherwise pressurized.

[0041] The primary airflow 154 can be defined by a first pressure, while the compressed primary airflow 158 can be defined by a second pressure greater than the first pressure. It should be understood that the first and second pressures can vary along the stages of the respective LP compressor 114 and HP compressor 116.

[0042] The balancing chamber 108 can be fluidly connected to a compressed primary gas flow 158 via a balancing chamber inlet line 130 to define a first fluid 160 within the balancing chamber 108. However, the compressed primary gas flow 158 within the balancing chamber inlet line 130 can be heated via a heat exchanger 132 or filtered via a particle separator 134 before flowing into the balancing chamber 108. The first fluid 160 can be defined by a second pressure. At least a portion of the first fluid 160 within the balancing chamber 108 can flow into a recovery chamber 136 to define a second fluid 162 at a third pressure less than the second pressure. It is envisioned that the seal 138 can be biased between a high-pressure region and a low-pressure region, such that fluid flows only from the high-pressure region to the low-pressure region. In other words, the seal 138 can be biased such that fluid flows only from the balancing chamber 108 into the recovery chamber 136 because the pressure of the first fluid 160 is higher than the pressure of the second fluid 162.

[0043] The second fluid 162 can be discharged directly from the recovery chamber 136 into the turbocharger section 124. Therefore, the second fluid 162 can be discharged from the recovery chamber 136 into the turbocharger section and discharged via the discharge line 140, where the second fluid 162 can be discharged back to the multistage compressor 100 (e.g., downstream of the LP compressor 114 and upstream of the HP compressor 116), or selectively discharged via the bypass line 146 to at least one of the secondary flow paths 148, or discharged via the turbine line 144 downstream of or within the turbine section.

[0044] The total thrust of the turbine engine can apply a longitudinal axial force on the drive shaft 102, which can ultimately be at least partially transmitted to the thrust bearing as a first axial force 110. The pressure of the second fluid 162 is sufficient to apply a second axial force 112 to the thrust bearing, which partially cancels (e.g., equal but opposite in magnitude) the first axial force 110. Therefore, the total axial force experienced across the thrust bearing 106 can be reduced. It is further envisioned that at least a portion of the compressed primary airflow 158 can be fluidly coupled to the turbine balance chamber inlet line 164 (which can be located in the turbine section of the turbine engine) and used to balance or cancel the axial force applied from the drive shaft 102 to the thrust bearing in the turbine section.

[0045] It is envisioned that during normal operation of the turbine engine, the fan section 126 can be disengaged or at least partially disengaged from the drive shaft 102 to ensure that the fan section 126 operates at an optimal rotational speed. When the fan section 126 is engaged with the drive shaft 102, at least a portion of the longitudinal axial force generated by the total thrust of the turbine engine can be transmitted to or through the fan section 126. However, when disengaged, the thrust bearing 106 experiences a greater longitudinal axial force as part of the longitudinal axial force no longer applied to the fan section 126. This, in turn, increases the total first axial force 110 applied to the thrust bearing 106. It is envisioned that the second axial force 112 generated by the balancing chamber 108 can at least partially counteract the first axial force 110 under all operating conditions, including when the fan section 126 is at least partially disengaged from the drive shaft 102.

[0046] The benefits of this disclosure include a thrust bearing in the compressor section having a longer flight time than a conventional thrust bearing in a conventional compressor section. As used herein, the term "flight time" or "wing time" can refer to the total amount of time or usage a particular component can have before it must be removed from the turbine engine and replaced, or otherwise repaired. For example, a conventional compressor section does not include a balance chamber. Therefore, a conventional thrust bearing in a conventional compressor section would be subjected to unrestricted (e.g., unimpeded) axial loads by the rotational forces of the drive shaft, which would wear down the conventional thrust bearing over time. However, a turbine engine as described herein includes a thrust bearing positioned close to the balance chamber, which can counteract or otherwise reduce the axial forces on the thrust bearing from the drive shaft through opposing axial forces. The use of a balance chamber can be envisioned to reduce the total axial forces experienced along the thrust bearing by 10-35% compared to a conventional thrust bearing in a conventional compressor section. This ultimately increases the total flight time of the thrust bearing relative to the flight time of a conventional thrust bearing.

[0047] A further benefit compared to conventional thrust bearings in conventional compressor sections is that the thrust bearings are designed to operate over a wider range of turbine engine operating conditions. As mentioned above, conventional compressor sections do not include a balancing chamber. Therefore, as described herein, the total axial force experienced across a conventional thrust bearing will be higher across all operating conditions than across a conventional thrust bearing. This, in turn, means that if the thrust bearing and conventional thrust bearing were identical, the conventional thrust bearing would experience a greater total axial force under high-load conditions (e.g., fan section separation) compared to the thrust bearing described herein. One way to help ensure that conventional thrust bearings do not fail is to increase their size or material properties, thereby increasing their overall cost and footprint. As described herein, thrust bearings can withstand the operating conditions of turbine engines without requiring increased size or material properties.

[0048] Furthermore, the offsetting of axial forces across the thrust bearing from the drive shaft allows for increased operation of the turbine engine compared to conventional turbine engines that include conventional thrust bearings. Imagine that the rotational force on the drive shaft can increase with its rotational speed. The higher the drive shaft's rotational speed, the faster the compressor section rotates, which further includes or pressurizes the primary airflow. This ultimately improves the overall efficiency or power output of the turbine engine. In other words, it increases the turbine engine's total thrust. However, a drawback of increasing total thrust is the higher axial force exerted on the thrust bearing. However, the balancing chamber, as described herein, can be used to at least partially counteract the increased axial load. At least partially counteracting the increased axial load helps ensure that the turbine engine can operate under conditions where the drive shaft has a relatively high rotational speed. Furthermore, as the pressure of the primary airflow in the compressor section increases, the fluid pressure within the balancing chamber also increases. This means that the axial force exerted by the balancing chamber on the thrust bearing also increases. Therefore, the axial force exerted by the balancing chamber on the thrust bearing can vary at least partially with the turbine engine's operating conditions. This ultimately results in an increased power output for the turbine engine compared to conventional turbine engines.

[0049] A further benefit of this disclosure compared to conventional balance chambers used in conventional turbine engines includes a more efficient balance chamber. For example, a conventional balance chamber (e.g., a balance chamber located within the turbine section) can draw fluid from the compressor section or turbine section to generate the required axial force. This results in a 1% to 2% fuel combustion loss in a conventional turbine engine. In other words, including a conventional balance chamber can reduce the fuel efficiency of a turbine engine by 1% to 2% compared to a conventional turbine engine without a conventional balance chamber. However, a balance chamber as described herein draws fluid from the compressor section and recirculates at least a portion of it (e.g., through a recovery chamber) back through the turbine engine for use in generating thrust or cooling turbine engine components. This, in turn, increases the efficiency of the balance chamber relative to a conventional balance chamber. A balance chamber as described herein can result in a 0.06% to 0.12% fuel combustion loss in a turbine engine.

[0050] Further benefits of this disclosure include a balance chamber located within the compressor section. Conventional turbocharged engines do not include a compressor balance chamber for various reasons. First, if a conventional turbocharged engine included a conventional balance chamber in its compressor section (e.g., a balance chamber found in the turbine section), the compressor materials would have to be upgraded. This is because for the balance chamber to function, it must draw air from a relatively high-temperature region and deliver it to a region located in a relatively low-temperature region relative to the high-temperature region. The low-temperature region is not rated (e.g., capable of withstanding) air from the high-temperature region. Therefore, conventional turbocharged engines require increased material properties in the low-temperature region to better withstand the high temperatures. However, a balance chamber, as described herein, can include one or more cooling elements (e.g., heat exchangers) arranged along the balance chamber inlet line. This lowers the temperature of the air supplied to the balance chamber, thus eliminating the need to change the compressor section materials to withstand the relatively high-temperature air. Second, if a conventional turbocharged engine included a conventional balance chamber in its compressor section (e.g., a balance chamber found in the turbine section), the air from the balance chamber would not be able to exit without adversely affecting the turbocharged engine. For example, a conventional turbocharged balance chamber is located in the exhaust section or near the LP turbine. Therefore, a conventional turbine balancing chamber can discharge fluid from its interior to the LP turbine or exhaust section without adverse effects. If this same arrangement were placed in the compressor section (e.g., the balancing chamber would discharge directly to the LP compressor), the efficiency of the compressor section would be adversely affected. However, as described herein, discharging fluid from the balancing chamber to a recovery chamber, which selectively discharges fluid from the recovery chamber to a location capable of receiving fluid from the balancing chamber (e.g., bypass lines, turbine lines, HP compressors, etc.), also without adverse effects.

[0051] Furthermore, the inclusion of a balance chamber within the compressor section offers additional benefits. First, the turbine engine's structure creates additional space within the compressor section that can be used to encapsulate the balance chamber. In conventional turbine engines, this space is unused. Second, conventional balance chambers located within the turbine section require two seals (one along the outer diameter and one along the inner diameter) to function properly. However, the balance chamber described herein requires only a single seal along the outer diameter of the balance chamber. This, in turn, results in reduced weight, additional usable space, and lower leakage losses compared to conventional balance chambers.

[0052] Within the scope not yet described, different features and structures of each aspect may be combined or substituted for one another as needed. A feature not shown in all examples is not to be interpreted as being forbidden, but rather is done for the sake of brevity. Therefore, various features of different aspects may be mixed and matched as needed to form new aspects, whether or not the new aspects are explicitly described. All combinations or permutations of the features described herein are covered by this disclosure.

[0053] This written description uses examples to illustrate aspects of the disclosure described herein, including best practices, and also enables any person skilled in the art to practice aspects of the disclosure, including making and using any apparatus or system and performing any combination of methods. The patentable scope of aspects of this disclosure is defined by the claims, and may include other examples that would occur to a person skilled in the art. Such other examples are intended to fall within the scope of the claims if they have structural elements that are not indistinguishable from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

[0054] Further details are provided by the following topics:

[0055] A turbine engine includes: a drive shaft rotatable about an axis; a multi-stage compressor section surrounding and driven by the drive shaft; a turbine section surrounding and operatively coupled to the drive shaft; a thrust bearing disposed between the drive shaft and at least a portion of the multi-stage compressor section and rotatably supporting the drive shaft; and a balancing chamber located at least partially axially upstream of the thrust bearing relative to the axis and fluidly coupled to at least one of the stages of the multi-stage compressor section; wherein, during operation of the turbine engine, a first axial force is applied to the thrust bearing by the drive shaft in a longitudinal direction relative to the axis, and a second axial force is applied by the balancing chamber in a direction opposite to the first axial force.

[0056] According to any of the foregoing clauses, the turbine engine, wherein the multi-stage compressor section further includes a first portion and a second portion, the first portion having a first airflow at a first pressure, the second portion being downstream of the first portion having a second airflow at a second pressure higher than the first pressure, and wherein the balancing chamber is fluidly coupled to the second portion such that at least a portion of the second airflow is supplied to the balancing chamber.

[0057] In any of the preceding clauses, the turbine engine is wherein the balance chamber is positioned radially inward from the first portion relative to the axis.

[0058] The turbine engine according to any of the foregoing clauses, wherein the first part is a low-pressure compressor and the second part is a high-pressure compressor.

[0059] The turbine engine according to any of the foregoing clauses, wherein the low-pressure compressor includes a multi-stage turbocharger section arranged along a downstream portion of the low-pressure compressor, and wherein the balance chamber is positioned radially inward from the turbocharger section relative to the axis.

[0060] The turbine engine according to any of the foregoing clauses, wherein the balance chamber is fluidly connected to the high-pressure compressor between the first and fourth stages of the high-pressure compressor.

[0061] The turbocharger section is the furthest axial downstream stage of the low-pressure compressor, according to any of the foregoing clauses of the turbocharger engine.

[0062] The turbine engine according to any of the foregoing clauses further includes a balance chamber inlet line fluidly connecting the balance chamber and the radially inward or radially outward portion of the second portion relative to the axis.

[0063] The turbine engine according to any of the foregoing clauses further includes: a heat exchanger thermally coupled to the balance chamber inlet line and configured to cool at least a portion of the second fluid before the second fluid enters the balance chamber; and a particle separator fluidly coupled to the balance chamber inlet line and configured to filter the fluid from the second portion before it enters the balance chamber.

[0064] The turbine engine according to any of the foregoing clauses further includes a recovery chamber fluidly connected to the balance chamber.

[0065] The turbine engine according to any of the foregoing clauses, wherein the recovery chamber is arranged radially outward from the balance chamber relative to the axis.

[0066] The turbine engine according to any of the foregoing clauses further includes: a primary flow path having a primary airflow and extending through the multi-stage compressor section and the turbine section; and a secondary flow path having a secondary airflow and disposed upstream of the multi-stage compressor section; wherein the recovery chamber is configured to discharge fluid from the recovery chamber to at least one of the supercharger section, downstream or downstream portion of the turbine section, the secondary flow path, or the atmosphere.

[0067] The turbine engine according to any of the foregoing clauses further includes an exhaust line that fluidly connects the recovery chamber to at least one of the supercharger section, the turbine section, the secondary flow path, or the atmosphere.

[0068] According to any of the preceding clauses, the turbine engine wherein the discharge line fluidly connects the recovery chamber to the supercharger section, the turbine section and the atmosphere, and selectively fluidly connects to the multistage compressor section or the secondary flow path.

[0069] According to any of the preceding clauses, the turbine engine wherein the secondary flow path includes an airflow configured to cool the downstream portion of the turbine engine, provide reverse thrust to the turbine engine, or contribute to the thrust of the turbine engine.

[0070] The turbine engine according to any of the foregoing clauses further includes a seal disposed between the balance chamber and the recovery chamber.

[0071] According to any of the foregoing clauses, the multi-stage compressor section further includes a turbocharger section, and the seal is radially spaced from the turbocharger section relative to the axis.

[0072] The turbocharger engine according to any of the foregoing clauses, wherein the turbocharger section and the seal both extend circumferentially about the entire axis, and wherein a first radius is defined between the innermost radial portion of the turbocharger section and the axis, and a second radius smaller than the first radius is defined between the innermost radial portion of the seal and the axis.

[0073] The turbine engine according to any of the foregoing clauses further includes a recovery chamber fluidly coupled to the balancing chamber, wherein the balancing chamber and the recovery chamber each extend circumferentially about the entire axis.

[0074] The turbine engine according to any of the foregoing clauses further includes a turbine balance chamber located within the turbine section, wherein the turbine balance chamber is fluidly coupled to a portion of the multi-stage compressor section.

[0075] A multistage compressor section includes: a drive shaft rotatable about an axis; a thrust bearing disposed between the drive shaft and at least a portion of the multistage compressor section and rotatably supporting the drive shaft; and a balancing chamber located at least partially axially upstream of the thrust bearing relative to the axis and fluidly coupled to at least one of the stages of the multistage compressor section; wherein, during operation of the multistage compressor section, a first axial force is applied to the thrust bearing by the drive shaft in a forward-backward direction relative to the axis, and a second axial force is applied by the balancing chamber in a direction opposite to the first axial force.

Claims

1. A turbine engine characterized by, Comprising: a drive shaft rotatable about an axis; a multi-stage compressor section surrounding the drive shaft and driven by the drive shaft; a turbine section surrounding the drive shaft and operably coupled to the drive shaft; a thrust bearing disposed between the drive shaft and at least a portion of the multi-stage compressor section and rotationally supporting the drive shaft; a balance cavity at least partially axially upstream of the thrust bearing relative to the axis and fluidly coupled to at least one stage of the multi-stage compressor section; and a recovery cavity fluidly coupled to the balance cavity; wherein, during operation of the turbine engine, a first axial force is exerted by the drive shaft on the thrust bearing in a forward or aft direction relative to the axis, and a second axial force is exerted by the balance cavity in a direction opposite the first axial force. wherein, 2. The turbine engine of claim 1, wherein, the multi-stage compressor section further comprises a first portion having a first airflow at a first pressure and a second portion downstream of the first portion having a second airflow at a second pressure higher than the first pressure, and wherein the balance cavity is fluidly coupled to the second portion such that at least a portion of the second airflow is supplied to the balance cavity. wherein, 3. The turbine engine of claim 2, wherein, the balance cavity is positioned radially inward relative to the axis from the first portion. wherein, 4. The turbine engine of claim 3, wherein, the first portion is a low pressure compressor and the second portion is a high pressure compressor. wherein, 5. The turbine engine of claim 4, wherein, the balance cavity is fluidly coupled to the high pressure compressor between a first stage and a fourth stage of the high pressure compressor. wherein, 6. The turbine engine of claim 5, wherein, the low pressure compressor includes a booster section disposed multi-staged along a downstream portion of the low pressure compressor, and wherein the balance cavity is positioned radially inward relative to the axis from the booster section. wherein, 7. The turbine engine of claim 6, wherein, the booster section is a most axially downstream stage of the low pressure compressor. further comprising a balance cavity inlet line fluidly coupling the balance cavity and a radially inward portion or a radially outward portion of the second portion relative to the axis.

8. The turbine engine of claim 2, wherein, further comprising:

9. The turbine engine of claim 8, wherein, a heat exchanger thermally coupled to the balance cavity inlet line and configured to cool at least a portion of a second fluid prior to the second fluid entering the balance cavity; and a particulate separator fluidly coupled to the balance cavity inlet line and configured to filter fluid from the second portion prior to the fluid entering the balance cavity. wherein, the recovery cavity is disposed radially outward relative to the axis from the balance cavity.

10. The turbine engine of claim 1, wherein, further comprising: a primary flow path having a primary airflow and extending through the multi-stage compressor section and the turbine section; and 11. The turbine engine of claim 1, wherein, a secondary flow path having a secondary airflow and disposed upstream of the multi-stage compressor section; ​ ​ ​ wherein the recovery cavity is configured to exhaust fluid from the recovery cavity to at least one of a booster section, a downstream or downstream portion of the turbine section, the secondary flow path, or an atmosphere.

12. The turbine engine of claim 11, wherein, further comprising an exhaust line fluidly coupling the recovery cavity to at least one of the booster section, the turbine section, the secondary flow path, or an atmosphere.

13. The turbine engine of claim 12, wherein, wherein, the exhaust line fluidly couples the recovery cavity to the booster section, the turbine section, and the atmosphere, and selectively fluidly couples to the multi-stage compressor section or the secondary flow path.

14. The turbine engine of claim 11, wherein, wherein, the secondary gas flow is configured to cool a downstream portion of the turbine engine, provide reverse thrust of the turbine engine, or assist in thrust of the turbine engine.

15. The turbine engine of claim 1, wherein, further comprising a seal disposed between the balance cavity and the recovery cavity, wherein the multi-stage compressor section further comprises a booster section, and wherein the seal is radially spaced from the booster section relative to the axis.

16. The turbine engine of claim 15, wherein, wherein, the booster section and the seal both extend circumferentially around the entire axis, and wherein a first radius is defined between a radially innermost portion of the booster section and the axis, and a second radius, smaller than the first radius, is defined between a radially innermost portion of the seal and the axis.

17. The turbine engine of any one of claims 1-9, wherein, wherein the balance cavity and the recovery cavity each extend circumferentially around the entire axis.

18. The turbine engine of any one of claims 1-9, wherein, further comprising a turbine balance cavity within the turbine section, wherein the turbine balance cavity is fluidly coupled to a portion of the multi-stage compressor section.

19. A multi-stage compressor section characterized by, including: a drive shaft rotatable about an axis; a thrust bearing disposed between the drive shaft and at least a portion of the multi-stage compressor section and rotatably supporting the drive shaft; a balance cavity at least partially axially upstream of the thrust bearing relative to the axis and fluidly coupled to at least one stage of the multi-stage compressor section; and a recovery cavity fluidly coupled to the balance cavity; wherein, during operation of the multi-stage compressor section, a first axial force is exerted by the drive shaft to the thrust bearing in a forward or aft direction relative to the axis, and a second axial force is exerted by the balance cavity in a direction opposite the first axial force.

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