Turbine engine with high acceleration and low blade rotation

Abstract

A turbine engine having at least a compressor section, a combustor section, a turbine section and a set of airfoils. The airfoils include geometrical characteristics that produce a high contraction ratio (CR), a low blade turning (BT) at a radially inward location of the airfoils, a low solidity or a low aspect ratio (AR).

Description

[0001] This application is a divisional application of the invention patent application filed on March 10, 2021, with application number 202110261516.1 and invention title "Turbine Engine with Airfoil of High Acceleration and Low Blade Rotation". Technical Field

[0002] This disclosure generally relates to airfoils for engines, and more specifically to the geometry of said airfoils. Background Technology

[0003] A turbine engine, and especially a gas or combustion turbine engine, is a rotating engine that extracts energy from a stream of combustion gases passing through the engine and transfers it to multiple rotating turbine blades.

[0004] A turbine engine includes, but is not limited to, a front fan assembly, a rear fan assembly, a high-pressure compressor for compressing air flowing through the engine, a combustor for mixing fuel with compressed air so that the mixture can be ignited, and a high-pressure turbine. The high-pressure compressor, combustor, and high-pressure turbine are sometimes collectively referred to as the core engine.

[0005] In at least some turbine engines, at least one turbine rotates in a direction opposite to other rotating components within the engine. In some embodiments, the counter-rotating low-pressure turbine includes: an outer drum having a first set of stages rotatably coupled to a front fan assembly; and an inner drum having an equal number of stages rotatably coupled to a rear fan assembly.

[0006] A turbine engine comprises several components that utilize airfoils. As a non-limiting example, the airfoil may be located in the engine turbine, compressor, or fan. The geometry of the airfoil affects various properties, such as, but not limited to, the contraction ratio, blade rotation, rigidity, or aspect ratio. Summary of the Invention

[0007] In one aspect, this disclosure relates to a turbine engine comprising: at least one blade carried by a rotor and rotating about a rotation axis, the blade comprising: an outer wall defining a pressure side and a suction side extending in a chordal direction between a leading edge and a trailing edge and extending in a transverse direction between a root and a tip; a mid-arc extending between the leading edge and the trailing edge and intersecting the leading edge to define a leading edge intersection point and intersecting the trailing edge to define a trailing edge intersection point; and an inlet angle β. in Entrance angle β in Defined by the angle between the line parallel to the mid-arc line at the intersection of the leading edges and the axis of rotation; exit angle β out Exit angle β outDefined by the angle between a line parallel to the mid-curve at the trailing edge intersection and the axis of rotation, wherein the blade has a shrinkage ratio (CR) greater than 0.45 along at least 80% of the span of at least one blade, wherein CR is determined by the following formula:

[0008]

[0009] The blades have a blade rotation (BT) of less than 100 degrees along at least 30% of the span, wherein the blade rotation is determined by the following formula:

[0010]

[0011] In another aspect, the present invention relates to an airfoil configured to rotate about an axis of rotation and comprising: an outer wall defining a pressure side and a suction side extending in a chordal direction between a leading edge and a trailing edge and extending in a transverse direction between a root and a tip; a mid-arc extending between the leading edge and the trailing edge and intersecting the leading edge to define a leading edge intersection point and intersecting the trailing edge to define a trailing edge intersection point; and an inlet angle β. in Entrance angle β in Defined by the angle between the line parallel to the mid-arc line at the intersection of the leading edges and the axis of rotation; exit angle β out Exit angle β out Defined by the angle between a line parallel to the mid-curve at the intersection of the trailing edges and the axis of rotation, wherein the airfoil has a contraction ratio (CR) greater than 0.45 along at least 80% of the span of at least one blade, wherein CR is determined by the following formula:

[0012]

[0013] The airfoil has a blade rotation (BT) of less than 100 degrees along at least 30% of its span, wherein the blade rotation is determined by the following formula:

[0014] Attached Figure Description

[0015] In the attached diagram:

[0016] Figure 1 This is a schematic cross-sectional view of a gas turbine engine.

[0017] Figure 2 Is it possible to... Figure 1 A perspective view of the airfoil used in conjunction with a gas turbine.

[0018] Figure 3 yes Figure 2 A schematic diagram of the airfoil profile.

[0019] Figure 4 These are multiple components placed on the engine. Figure 2 A schematic diagram of the airfoil component.

[0020] Figure 5 It is placed on the rotatable part Figure 2 Side view of the airfoil component. Detailed Implementation

[0021] This specification focuses primarily on airfoils with a unique profile, possessing a predetermined contraction ratio (CR) and a predetermined blade rotation (BT), which together provide the airfoil with the ability to reduce boundary layer growth from the leading edge to the trailing edge. This profile is usable in a wide range of environments compared to conventional turbine engines, including those with high direct or relative speeds and high centrifugal forces. The blade rigidity, or aspect ratio (AR), can also be controlled to further enhance the unique profile's ability to delay boundary layer growth. The unique profile also reduces manufacturing and material costs associated with turbine engines.

[0022] As used herein, the term "upstream" refers to the direction opposite to the direction of fluid flow, and the term "downstream" refers to the direction in the same direction as the direction of fluid flow. The terms "forward" or "forward" mean in front of something, while "backward" or "backward" means behind something. For example, in the context of fluid flow, forward / forward can mean upstream, and backward / backward can mean downstream. Although various elements will be described as a "set," it should be understood that a "set" can include any number of corresponding elements, including only one element.

[0023] Additionally, as used herein, the term "radial" or "radially" refers to a direction away from a common center. For example, in the context of a turbine engine, radial refers to the direction of a ray extending between the engine's central longitudinal axis and the outer circumferential direction. Furthermore, as used herein, the term "group" or "set" of elements can refer to any number of elements, including a single element.

[0024] 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 in understanding this disclosure and do not impose limitations, particularly on the location, orientation, or use of aspects of this disclosure described herein. Unless otherwise stated, connection references (e.g., attachment, coupling, fixing, fastening, joining, and engagement) should be interpreted broadly and may include intermediate members between sets of elements as well as relative movement between elements. Thus, connection references do not necessarily imply a direct connection and fixation relationship between two elements. Exemplary figures are for illustrative purposes only, and the dimensions, positions, order, and relative sizes reflected in the accompanying figures may vary.

[0025] As used herein, the terms “forward” or “upstream” refer to a component that moves toward the engine inlet, or is relatively closer to the engine inlet compared to another component. The terms “rearward” or “downstream” used in conjunction with “forward” or “upstream” refer to a component that moves toward the rear or outlet of the engine, or is relatively closer to the engine outlet compared to another component. Additionally, as used herein, the terms “radial” or “radially” refer to the dimension extending between the central longitudinal axis of the engine and the outer circumferential direction of the engine. Furthermore, as used herein, the terms “group” or “set” of elements can refer to any number of elements, including a single element.

[0026] 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 in understanding this disclosure and do not impose limitations, particularly on the location, orientation, or use of aspects of this disclosure described herein. Unless otherwise stated, connection references (e.g., attachment, coupling, connection, and joining) should be interpreted broadly and may include intermediate members between sets of elements as well as relative movement between elements. Thus, connection references do not necessarily imply a direct connection and fixation relationship between two elements. Exemplary figures are for illustrative purposes only, and the dimensions, positions, order, and relative sizes reflected in the accompanying figures may vary.

[0027] Figure 1This is a schematic cross-sectional view of a turbine engine 10 for use in an aircraft. The turbine engine 10 has a generally longitudinal axis or 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, 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.

[0028] Fan section 18 includes a fan housing 40 surrounding fan 20. Fan 20 includes a plurality of fan blades 42 arranged radially around centerline 12. HP compressor 26, combustor 30 and HP turbine 34 form engine core 44 of turbine engine 10 that generates combustion gases. Engine core 44 is surrounded by core housing 46, which can be coupled to fan housing 40.

[0029] An HP shaft or spool 48, coaxially arranged around the centerline 12 of the turbine engine 10, drives the HP turbine 34 to the HP compressor 26. An LP shaft or LP spool 50, coaxially arranged within a larger diameter annular HP spool 48 around the centerline 12 of the turbine engine 10, drives the LP turbine 36 to the LP compressor 24 and the fan 20. The HP spool 48 and LP spool 50 are rotatable about the engine centerline and connected to multiple rotatable elements that collectively define an inner rotor / stator 51. Although shown as a rotor, it is conceivable that the inner rotor / stator 51 could be a stator.

[0030] 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 blades 60 and 62 to compress or pressurize the fluid flow through the stage. In a single compressor stage 52 or 54, the multiple compressor blades 56 and 58 may be arranged in an annular pattern and may extend radially outward from the blade platform relative to the centerline 12 to the blade tips, while the corresponding static compressor blades 60 and 62 are positioned upstream of and adjacent to the rotating compressor blades 56 and 58. Note that... Figure 1 The number of blades, impellers, and compressor stages shown is chosen for illustrative purposes only, and other numbers are possible.

[0031] Compressor blades 56, 58 for the compressor stage can be mounted to (or integrated into) a disc 61, which is mounted to a corresponding one of the HP spool 48 and the LP spool 50. Static compressor impellers 60, 62 for the compressor stage can be mounted circumferentially to the core housing 46.

[0032] HP turbine 34 and LP turbine 36 each comprise multiple turbine stages 64 and 66, wherein a set of turbine blades 68 and 70 rotates 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 an annular pattern and may extend radially outward relative to a centerline 12, while the corresponding static turbine blades 72 and 74 are positioned upstream of and adjacent to the rotating blades 68 and 70. It should be noted that... Figure 1 The number of blades, impellers, and turbine stages shown is chosen for illustrative purposes only, and other numbers are possible.

[0033] Blades 68 and 70 for the turbine stage can be mounted to disk 71, which is mounted to one of the HP spool 48 and LP spool 50 respectively. Static turbine blades 72 and 74 for the turbine stage can be mounted to the core housing 46 in a circumferential arrangement.

[0034] As a complement to the rotor section, the stationary parts of the turbine engine 10 (e.g., the static compressor impellers and turbine blades 60, 62, 72, 74 in the compressor section 22 and turbine section 32) are also referred to individually or collectively as the outer rotor / stator 63. As shown, the outer rotor / stator 63 may refer to the combination of non-rotating elements in the entire turbine engine 10. Alternatively, the outer rotor / stator 63, which is external to at least a portion of the inner rotor / stator 51, may be designed to rotate.

[0035] 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 is ignited, producing combustion gases. HP turbine 34 extracts some work from these gases, which drives HP compressor 26. The combustion gases are discharged to LP turbine 36, which extracts additional work to drive LP compressor 24, and the exhaust gases are finally discharged from turbine engine 10 via exhaust section 38. The drive of LP turbine 36 drives LP spool 50, causing fan 20 and LP compressor 24 to rotate.

[0036] It is conceivable that a gear drive or gearbox may be included within at least a portion of the turbine engine 10. The gear drive may be configured to rotate one or more portions of the turbine engine 10 at a desired rotational speed. For example, the LP spool 50 may be segmented such that the portion of the LP spool 50 connected to the LP turbine 36 serves as an input to a gearbox on the LP spool. The remaining portion of the LP spool 50 may serve as an output from the gearbox on the LP spool and is operatively coupled to the fan 20 and the LP compressor 24. The gearbox on the LP spool may be configured to provide gear reduction between the LP turbine 36, the LP compressor 24, and the fan 20. Thus, the LP compressor 24 and the fan 20 may rotate at a first rotational speed, while the LP turbine may rotate at a second rotational speed different from the first rotational speed. It will be understood that this is a non-limiting example, and the gear drive may be applied to any suitable portion of the turbine engine 10.

[0037] A portion of the pressurized airflow 76 can be drawn from the compressor section 22 as bleed air 77. Bleed air 77 can be drawn from the pressurized airflow 76 and supplied to engine components requiring cooling. The temperature of the pressurized airflow 76 entering the combustor 30 is significantly increased. Thus, the cooling provided by bleed air 77 is necessary for operating these engine components in elevated temperature environments.

[0038] The remaining airflow 78 bypasses the LP compressor 24 and engine core 44, and exits the turbine engine 10 via a stationary blade array (more specifically, an outlet guide blade assembly 80 comprising multiple airfoil guide blades 82) at the fan exhaust side 84. More specifically, a circumferentially extending row of radially extending airfoil guide blades 82 is used near the fan section 18 to provide some directional control of the airflow 78.

[0039] Some of the air supplied by fan 20 can bypass engine core 44 and be used to cool portions of turbine engine 10, particularly the hot sections, and / or to cool or power other aspects of the aircraft. In the case of a turbine engine, the hot sections are typically downstream of combustor 30, particularly turbine section 32, with HP turbine 34 being the hottest section as it is 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.

[0040] It will be understood that the turbine engine 10 and its components described herein can be implemented in other turbine engines (including, but not limited to, turbojet engines, turboprop engines, turboshaft engines, and turbofan engines). For example, the turbine engine 10 can be a bladeless counter-rotating turbine (CRT) engine, in which both the outer rotor / stator 63 and the inner rotor / stator 51 can be rotors.

[0041] Figure 2 This is a schematic partial cross-sectional view of airfoil assembly 102. Airfoil assembly 102 may include platform 110, dovetail joint 122, and airfoil 104 defined by profile 124. Airfoil 104 may be any airfoil, such as blades or impellers in fan section 18, compressor section 22, or turbine section 32, as desired. It will be understood that, in a non-limiting example, airfoil assembly 102 may also include any suitable components within a turbine engine, including shields, hangers, struts, platforms, inner or outer belts.

[0042] To explain the accompanying drawing, a coordinate system has been set up, in which the X-axis can be defined by the centerline 12 of the turbine engine 10, the Y-axis can be defined by the circumferential axis of the turbine engine 10, and the Z-axis can be defined by the radial axis of the turbine engine 10.

[0043] Airfoil 104 includes an outer wall 120 defining a pressure side 130 and a suction side 132. The outer wall 120 may extend around the entire outer periphery of airfoil 104 along the pressure side 130 and suction side 132. Thus, the outer wall 120 extends between a leading edge 112 and a trailing edge 114 to define a chordal direction Cd, and also extends radially along the Z-axis between a root 108 and a tip 106 to define a transverse direction Sd. The span S may be defined as the total length of the airfoil in the transverse direction Sd from the root 108 to the tip 106.

[0044] The airfoil assembly 102 may also include a platform 110 connected at a root 108 to the airfoil 104. In one example, the airfoil 104 may be a blade of a turbine engine 10. The platform 110 may be mounted to a rotating structure to rotate about the X-axis, thereby causing the airfoil to rotate about the X-axis. Alternatively, the platform 110 may be mounted to a non-rotating structure, resulting in a non-rotating airfoil. A dovetail tenon 122 may hang from the platform 110. In this case, the platform 110 may form at least a portion of the dovetail 122.

[0045] Multiple airfoil assemblies 102 can be arranged circumferentially about the X-axis in an adjacent relationship. Dovetail tenons 122 can be received in a rotating or stationary disk to influence the circumferential arrangement.

[0046] The platform 110 shown can be a continuous, uninterrupted surface. Alternatively, holes, channels, pipes, cracks, slots, or any other known features can be placed throughout the platform 110. These various exemplary features of the platform can be used for a variety of reasons to improve overall engine efficiency. These features can be used as dust collectors, cooling vents, or aerodynamic efficiency enhancers.

[0047] The dovetail tenon 122 can be configured to be mounted to at least a portion of the inner rotor / stator 51 or the outer rotor / stator 63 of the turbine engine 10. The dovetail tenon 122 may include a set of inlet channels 116 (exemplarily shown as three inlet channels) extending through the dovetail tenon 122 to provide a communication path for fluid flow 100 to enter the airfoil 104. Alternatively, any number of inlet channels 116 may pass through the dovetail tenon 122 to provide fluid communication with the interior of the airfoil 104. It should be understood that the dovetail tenon 122 is shown in cross-section such that the inlet channels 116 are received within the body of the dovetail tenon 122.

[0048] Multiple outlets 118 may extend adjacent to the outer wall 120. The outlets 118 are shown positioned along the outer wall 120. The outlets 118 may be positioned along the leading edge 112 and trailing edge 114 at the root 108 of the airfoil 104 or near the tip 106 of the airfoil 104. The outlets 118 may be positioned on the outer wall 120 of the pressure side 130 or the suction side 132. Any number of outlets 118 may be present. Multiple outlets 118 may be present, with all outlets 118 having the same size and shape. The outlets 118 may have various sizes. For example, an outlet 118 may be as small as a pin or as large as the total length of the airfoil 104 in the transverse direction Sd or the chordal direction Cd.

[0049] The outlet 118 is shown as a circular injection orifice. In a non-limiting example, the outlet 118 may also include an in-line diffuser, a diffusion channel, an venting channel, a membrane orifice, or a channel. Although shown as circular, in a non-limiting example, the outlet 118 may also have any suitable geometric profile, including elliptical, square with rounded corners, or asymmetrical / irregular shapes. The outlet 118 may be a continuous orifice or channel leading into the interior of the airfoil and communicating with the fluid flow 100. Alternatively, the outlet 118 may include other components, such as porous materials, solid materials, membranes, meshes, and / or any other reasonable material. These other components may be placed at or near the outlet 118.

[0050] Airfoil 104 may be defined by profile 124, which may produce improved efficiency characteristics. For example, profile 124 of airfoil 104 may produce a preferred contraction ratio (CR), blade rotation (BT), rigidity, or aspect ratio (AR). Profile 124 may be the same at the root 108 as it is at the tip 106. Alternatively, the profile of the root 108 may differ from the profile of the tip 106. If a cross-section is taken along the X-axis of rotation, the entire span S of airfoil 104 may have the same profile. Alternatively, portions of airfoil 104 may have different profiles 124. For example, if a cross-sectional view is taken at a first position (e.g., midway between the root 108 and the tip 106) and a second position (e.g., at or near the tip 106), the profile seen at the first position may differ from the profile seen at the second position.

[0051] Figure 3 This is a cross-sectional view of airfoil 104, and more specifically, a cross-sectional view of profile 124. Profile 124 may be defined with reference to well-known terms used to define the airfoil. For example, the mid-arc line 126 extending from the leading edge 112 to the trailing edge 114 is a line equidistant from the pressure side 130 and the suction side 132 of the outer wall 120.

[0052] Chord line 128 can be defined as a straight-line distance from leading edge 112 to trailing edge 114. As shown, for the illustrated high-cell airfoil, most of chord line 128 is not located within profile 124 itself, but extends through the pressure side 130 region of airfoil 104. Alternatively, any one of chord lines 128 may not be located within profile 124, and all chord lines 128 or any portion between chord lines 128 may be located within profile 124.

[0053] Profile 124 includes entrance angle β in and exit angle β out Entrance angle β in It can be defined by the angle between the X-axis and the line parallel to the mid-arc line 126 at the intersection of the X-axis and the leading edge. Similarly, the exit angle β out The intersection point can be defined by the angle between the X-axis and the line parallel to the mid-arc line 126 at the trailing edge intersection point. The leading and trailing edge intersection points can be defined by the intersection points of the mid-arc line 126 with the leading edge 112 or the trailing edge, respectively. Entry angle β in It can be positive relative to the X-axis, while the exit angle β out It can be negative relative to the X-axis.

[0054] It has been found that an airfoil 104 with profile 124 is the subject of this disclosure, which can quantify profile 124 using geometric characteristics such as high contraction ratio (CR) and low blade rotation (BT) along the span S.

[0055] The flow velocity (CR) of airfoil 104 can be defined as a geometric representation of profile 124, which can generate flow acceleration from the leading edge to the trailing edge. CR can be defined using the following formula:

[0056]

[0057] When compared with other airfoils, the CR value of airfoil 104 can be relatively high; therefore, CR can be defined as the high acceleration characteristic of airfoil 104. The CR value of airfoil 104 can vary across the span S of airfoil 104. For example, along at least 80% of the span S, the CR value can be greater than 0.55, while in the span S between 80% and 100%, the CR value can be greater than 0.45. The maximum CR value can occur at the mid-span, defined as a position equidistant from the root 108 to the tip 106 on airfoil 104, while the minimum value can occur at the root 108 of airfoil 104.

[0058] The blade rotation BT of airfoil 104 can typically be defined as an inlet angle β. in The fluid flow is represented by the impact on the leading edge 112 of the profile 124, and then along the curvature of the outer wall 120 of the profile 124 to the trailing edge 114, where the fluid flows at the exit angle β. out Leaving. The total amount of "rotation" of the fluid flow from the leading edge 112 to the trailing edge 114 can be defined as the total BT. BT can be defined using the following formula:

[0059]

[0060] When the airfoil 104 is defined by profile 124, the BT value is relatively low along at least a portion of the span S of the airfoil 104 compared to known airfoils, which translates to a very small curvature or radian. The BT value can vary along the span S of the airfoil 104. For example, the BT value can be less than 110 degrees at 100% of the span S, less than 100 degrees at a span S between 30% and 50%, and less than 90 degrees at at least 30% of the span S.

[0061] The maximum BT value can occur at a radially inward location of the airfoil 104, while the minimum BT value can occur at a radially outward location of the airfoil 104. As used herein, the radially inward location can be the portion of the airfoil 104 closest to the centerline 12 of the turbine engine 10, while the radially outward location can be the portion of the airfoil 104 furthest from the centerline 12. For example, the airfoil 104 can be included on the inner rotor 51, in which case the radially inward location can be the root 108 of the airfoil 104, and the radially outward location can be the tip 106 of the airfoil 104. Conversely, the airfoil 104 can be included on the outer rotor 63, such that the radially inward location can be the tip 106 of the airfoil 104, and the radially outward location can be the root 108 of the airfoil 104. Alternatively, one or more portions of the airfoil 104 can have the same BT value.

[0062] The airfoil 104, defined by profile 124, may have a high CR (concentration coefficient) falling within the aforementioned range, and a low BT (transfer coefficient) falling within the aforementioned range along at least a portion of its span. A combination of at least these two factors can delay boundary layer growth between the airflow and the outer wall 120 of the airfoil 104 on the pressure side 130 and suction side 132 from the leading edge 112 to the trailing edge 114. This delay in boundary layer growth can help ensure that the fluid flowing around the outer wall 120 of the airfoil 104 does not excessively separate and generate eddies or turbulence along or near the outer wall 120 of the airfoil 104. Excessive turbulence can lead to pressure losses and severely impact the overall efficiency of the turbine engine 10.

[0063] Figure 4 This is a top-down circumferential view of a portion of the annular component 134 of the turbine engine 10, showing two airfoil elements 104 spaced apart about the engine's circumferential Y-axis.

[0064] The effective axial length of each airfoil 104 can be determined by the axial chord length C extending along the X-axis of rotation. ax Limited. C ax It is the distance between the first radial line of the X-axis that intersects the leading edge and the second radial line of the X-axis that intersects the trailing edge. C ax This can be viewed as the X-axis component of a chord. The axial chord length C ax The axial chord C on the annular member 134 at the first position of the turbine engine 10 can vary depending on its location within the turbine engine 10. ax It can be larger than the other annular component 134 at the second location of the engine component. For each airfoil 104 on the corresponding annular component 134, the axial chord length C ax The same can be used. Alternatively, the axial chord length C of each airfoil 104 on the annular component 134 can be used.ax They can be different.

[0065] The leading edges 112 of the airfoil 104 may be spaced apart by a pitch P extending along the circumferential Y-axis. Throughout the annular component 134, the pitch P between adjacent airfoils 104 may be constant. In some cases, the pitch P is not constant between adjacent airfoils 104. For example, there may be four airfoils, with a first pitch P1 having a first value between the first and second airfoils, a second pitch P2 having a second value between the second and third airfoils, a third pitch P3 having a third value between the third and fourth airfoils, and a fourth pitch P4 having a fourth value between the fourth and first airfoils. Each of the first, second, third, fourth, and fifth values ​​may be different. Alternatively, the first and second values ​​may be the same, while the third and fourth values ​​may be different. All the first, second, third, and fourth values ​​may be the same. It will be understood that multiple combinations are possible.

[0066] As described herein, the airfoil 104 can significantly reduce the rigidity of the turbine engine 10. Rigidity can be defined as the axial chord length C. ax Compare the pitch P. The robustness can be related to the amount of profile 124, and therefore, in terms of fluid flow in the turbine engine 10, the robustness can be directly related to a portion of the wetted area. The robustness can be described using the following formula:

[0067]

[0068] In this case, the rigidity may be relatively low compared to known airfoil components. The rigidity of the turbine engine 10 can be between 0.6 and 1.2. Specifically, the rigidity of the turbine engine 10 can be between 0.7 and 0.9.

[0069] Reducing the rigidity or wetted area can provide the advantage of reduced pressure loss and thus improve overall turbine performance. In addition, since there can be fewer airfoil elements 104 with lower rigidity, the overall number of airfoil elements can be greatly reduced, which can lead to a significant reduction in the weight and cost of the turbine engine 10.

[0070] Figure 5 This is a side view of the airfoil 104 communicating with the annular component 134. The annular component 134 can be any suitable component adapted to rotate about a rotational X-axis. For example, the annular component 134 can be any part of the inner rotor 51 or the outer rotor 63. Alternatively, the annular component 134 can be a bearing, screw, cylinder, gear, or any other known object that can rotate about a rotational X-axis.

[0071] As mentioned earlier, due to the span S and axial chord length C of the airfoil 104 ax The airfoil 104 can have a significantly reduced aspect ratio (AR). AR can be defined as the ratio of the profile height or span S of the airfoil 104 to the axial chord length C. ax The ratio between them. A high AR can result in a relatively tall and narrow airfoil with a roughly rectangular cross-section, while a low AR can result in a stubby or short airfoil with a more square cross-section. AR can be defined by the following formula.

[0072]

[0073] When compared to known airfoils, the AR of airfoil 104 can be relatively low. The AR of turbine engine 10 can be 2 to 6. Specifically, the AR of turbine engine 10 can be 3 to 5.

[0074] Airfoil 104 can be defined by profile 124. Profile 124 allows airfoil 104 to have high CR and low BT in a radially inward position compared to other airfoils with lower CR and higher BT, enabling a turbine engine 10 with airfoil 104 having a low AR design. Airfoil 104 can have a lower AR, which allows for a smaller total number of airfoils 104 required for a given rigidity of turbine engine 10. This can be beneficial for performance as it can increase the Reynolds number of airfoil 104 and reduce the cost of turbine engine 10 because less material can be used to manufacture turbine engine 10 and airfoil 104.

[0075] As used herein, the terms “high” and “low” are used for comparison with past airfoil designs. For example, past airfoil designs could have CR values ​​ranging from 0.4 to 0.5 at the midspan and from 0.2 to 0.3 at the minimum position. In contrast, the airfoil 104 defined by profile 124 can have a relatively “high” CR value, with a CR value greater than 0.55 along at least 80% of the span S and a CR value greater than 0.45 in the span S between 80% and 100%.

[0076] Compared to conventional turbine engines with a single rotor and a single stator per stage, the airfoil 104 is suitable for CRT engines due to the relatively high relative speed of the turbine engine 10. For example, conventional turbines used in large commercial engines can rotate at speeds up to 8000 RPM, while CRT engines can rotate at relative speeds up to 12000 RPM. Known airfoils may fail when CRT engines are subjected to higher RPMs. The current airfoil 104 can have high CR and low BT at its radially inward position, making it more suitable for a wider range of relative speeds.

[0077] Airfoil 104 is better suited to withstand higher centrifugal forces. During operation of the turbine engine 10, airfoil 104 may experience higher centrifugal forces depending on its position within the compressor or turbine. Airfoil 104 can have a higher CR, lower BT, and lower AR at a radially inward position, which allows it to withstand higher centrifugal forces than other known airfoils. In return, as described above, airfoil 104 can withstand higher relative velocities.

[0078] Airfoil 104 can have high CR and low BT at a radially inward position, which allows for low AR and low rigidity. Low AR and low rigidity not only reduce losses and thus improve overall engine efficiency; however, they also significantly reduce the number of airfoils and the total weight of the airfoils, which greatly reduces the total cost of the turbine engine 10.

[0079] 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 combined 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 different 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.

[0080] Further aspects of the invention are provided by the subject matter of the following clauses:

[0081] 1. A turbine engine comprising: at least one blade carried by a rotor and rotatable about a rotation axis, the blade comprising: an outer wall defining a pressure side and a suction side, the pressure side and the suction side extending in a chordal direction between a leading edge and a trailing edge and extending in a transverse direction between a root and a tip; a mid-arc line extending between the leading edge and the trailing edge and intersecting the leading edge to define a leading edge intersection point, and intersecting the trailing edge to define a trailing edge intersection point; and an inlet angle β. in The entrance angle β in Defined by the angle between the line parallel to the mid-arc line at the intersection of the leading edges and the axis of rotation; exit angle β out The exit angle β out Defined by the angle between the line parallel to the mid-arc line at the intersection of the trailing edges and the axis of rotation, wherein the blade has a contraction ratio (CR) greater than 0.45 along at least 80% of the span of the at least one blade, wherein the CR is determined by the following formula:

[0082]

[0083] Wherein, the blade has a blade rotation (BT) of less than 100 degrees along at least 30% of the span, wherein the blade rotation is determined by the following formula:

[0084]

[0085] 2. The turbine engine according to any of the preceding clauses, wherein the β in The span from the root to the tip is constant.

[0086] 3. The turbine engine according to any of the preceding clauses, wherein the β out The span from the root to the tip is constant.

[0087] 4. The turbine engine according to any of the preceding clauses, wherein, along at least 80% of the span, CR is greater than 0.55.

[0088] 5. The turbine engine according to any of the preceding clauses, wherein the maximum CR value occurs at the mid-span of the blade between the root and the tip.

[0089] 6. The turbine engine according to any of the preceding clauses, wherein BT is less than 90 degrees along at least 30% of the span.

[0090] 7. The turbine engine according to any of the preceding clauses, wherein the angle along the entire span BT is less than 110 degrees.

[0091] 8. The turbine engine according to any of the preceding clauses, wherein the aspect ratio of the at least one blade is less than 6.

[0092] 9. The turbine engine according to any of the preceding clauses, wherein the aspect ratio is less than 5 and at least 3.

[0093] 10. The turbine engine according to any of the preceding clauses, wherein the at least one blade comprises a plurality of blades spaced circumferentially around the rotor.

[0094] 11. The turbine engine according to any of the preceding clauses, wherein the robustness is less than 0.9.

[0095] 12. The turbine engine according to any of the preceding clauses, wherein the aspect ratio of the plurality of blades is less than 5.0.

[0096] 13. The turbine engine according to any of the preceding clauses, wherein the CR is greater than 0.45 along at least 80% of the span, the BT is less than 100 degrees along at least 30% of the span, the aspect ratio is less than 5, and the rigidity is less than 0.9.

[0097] 14. The turbine engine according to any of the preceding clauses, wherein the rotor has two counter-rotating portions, wherein at least one blade is carried by at least one of the two counter-rotating portions.

[0098] 15. The turbine engine according to any of the preceding clauses, wherein the at least one blade comprises a first blade on one of the counter-rotating portions and a second blade on the other of the counter-rotating portions.

[0099] 16. The turbine engine according to any of the preceding clauses, wherein the outer wall defines an interior having at least one cooling air passage, and at least one cooling hole extends from the cooling air passage to the outer surface of the outer wall.

[0100] 17. An airfoil configured to rotate about an axis of rotation and comprising: an outer wall defining a pressure side and a suction side, the pressure side and the suction side extending in a chordal direction between a leading edge and a trailing edge and extending in a transverse direction between a root and a tip; a mid-arc extending between the leading edge and the trailing edge and intersecting the leading edge to define a leading edge intersection point, and intersecting the trailing edge to define a trailing edge intersection point; and an inlet angle β. in The entrance angle β in Defined by the angle between the line parallel to the mid-arc line at the intersection of the leading edges and the axis of rotation; exit angle β out The exit angle β out Defined by the angle between the line parallel to the mid-arc line at the intersection of the trailing edges and the axis of rotation, wherein the airfoil has a contraction ratio (CR) greater than 0.45 along at least 80% of the span of the at least one blade, wherein the CR is determined by the following formula:

[0101]

[0102] Wherein, the airfoil has a blade rotation (BT) of less than 100 degrees along at least 30% of the span, wherein the blade rotation is determined by the following formula:

[0103]

[0104] 18. The airfoil according to any of the preceding clauses, wherein the β in The span from the root to the tip is constant.

[0105] 19. The airfoil according to any of the preceding clauses, wherein the β out The span from the root to the tip is constant.

[0106] 20. The airfoil according to any of the preceding clauses, wherein CR is greater than 0.55 along at least 80% of the span.

[0107] 21. The airfoil according to any of the preceding clauses, wherein the maximum CR value occurs at the mid-span of the airfoil between the root and the tip.

[0108] 22. The airfoil according to any of the preceding clauses, wherein BT is less than 90 degrees along at least 30% of the span.

[0109] 23. The airfoil according to any of the preceding clauses, wherein the angle along the entire span BT is less than 110 degrees.

[0110] 24. The airfoil according to any of the preceding clauses, wherein the aspect ratio is less than 5 and at least 3.

[0111] 25. The airfoil according to any of the preceding clauses, wherein a plurality of circumferentially spaced airfoils exist around the rotor.

[0112] 26. The airfoil according to any of the preceding clauses, wherein the stiffness is less than 0.9.

[0113] 27. The airfoil according to any of the preceding clauses, wherein the CR is greater than 0.45 along at least 80% of the span, the BT is less than 100 degrees along at least 30% of the span, the aspect ratio is less than 5, and the stiffness is less than 0.9.

Claims

1. An airfoil operatively coupled to a rotor and configured to rotate about a rotation axis, characterized in that, The airfoil includes: The outer wall defines a pressure side and a suction side, which extend in a chordal direction between the leading edge and the trailing edge and in a transverse direction between the root and the tip to define a span (S). Axial chord length (C) ax The axial chord length extends between the leading edge and the trailing edge in an axial direction relative to the axis of rotation; and The aspect ratio (AR) of the airfoil is determined by the following formula: ; The aspect ratio (AR) is greater than or equal to 2 and less than or equal to 6 (2 < AR < 6); A middle arc line extends between the leading edge and the trailing edge, intersecting the leading edge to define a leading edge intersection point, and intersecting the trailing edge to define a trailing edge intersection point; Entrance angle β in The entrance angle β in Defined by the angle between the line parallel to the mid-arc line at the intersection of the leading edges and the axis of rotation; and Exit angle β out The exit angle β out Defined by the angle between the line parallel to the mid-arc line at the intersection of the trailing edges and the axis of rotation. The shrinkage ratio CR, which is greater than 0.45 along at least 80% of the span of the airfoil, is determined by the following formula: 。 2. The airfoil according to claim 1, characterized in that, in, The aspect ratio (AR) is greater than or equal to 3 and less than or equal to 5 (3 < AR < 5).

3. The airfoil according to claim 1, characterized in that, in, The airfoil has a blade rotation (BT) of less than 100 degrees along at least 30% of the span, wherein the blade rotation (BT) is determined by the following formula: 。 4. The airfoil according to claim 1, characterized in that, in, β in The span from the root to the tip is constant, or β. out The span from the root to the tip is constant.

5. The airfoil according to any one of claims 1-4, characterized in that, in, The airfoil is housed within the turbine engine.

6. The airfoil according to claim 5, characterized in that, in, The turbine engine is a counter-rotating turbine engine, and the rotor is either an inner rotor or an outer rotor.

7. An airfoil operatively coupled to a rotor and an assembly and configured to rotate about a rotation axis, characterized in that, The airfoil includes: An outer wall defining a pressure side and a suction side, the pressure side and the suction side extending in a chordal direction between the leading edge and the trailing edge and in a transverse direction between the root and the tip; A middle arc line extends between the leading edge and the trailing edge, intersecting the leading edge to define a leading edge intersection point, and intersecting the trailing edge to define a trailing edge intersection point; Entrance angle β in The entrance angle β in The angle between the line parallel to the middle arc at the intersection of the leading edges and the axis of rotation is defined. Exit angle β out The exit angle β out Defined by the angle between the line parallel to the mid-arc line at the intersection of the trailing edges and the axis of rotation; and The shrinkage ratio CR, which is greater than 0.55 along at least 80% of the span of the airfoil, is determined by the following formula: 。 8. The airfoil according to claim 7, characterized in that, in, The airfoil is included within at least two airfoils, wherein each of the at least two airfoils comprises: Axial chord length (C) ax The axial chord length extends between the leading edge and the trailing edge in an axial direction relative to the axis of rotation; The blade rotation (BT) has less than 100 degrees along at least 30% of the span, wherein the blade rotation (BT) is determined by the following formula: ； The airfoil stiffness (S1) of the at least two airfoil elements is determined by the following formula: The airfoil stiffness (S1) is greater than or equal to 0.6 and less than or equal to 1.2 (0.6). < Sl < 1.2); and The aspect ratio (AR) of the airfoil is determined by the following formula: The aspect ratio (AR) is greater than or equal to 2 and less than or equal to 6 (2 < AR < 6).

9. The airfoil according to any one of claims 7 or 8, characterized in that, in, The airfoil is housed within the turbine engine.

10. The airfoil according to claim 9, characterized in that, in, The turbine engine is a counter-rotating turbine engine, and the rotor is either an inner rotor or an outer rotor.

11. An airfoil operatively coupled to a rotor and an assembly, characterized in that, The airfoil includes: At least two airfoils, the at least two airfoils being carried by a rotor and configured to rotate about a rotation axis, the at least two airfoils being circumferentially spaced from each other relative to the rotation axis to define a pitch (P) therebetween, each of the at least two airfoils comprising: An outer wall defining a pressure side and a suction side, the pressure side and the suction side extending in a chordal direction between the leading edge and the trailing edge and in a transverse direction between the root and the tip; A middle arc line extends between the leading edge and the trailing edge, intersecting the leading edge to define a leading edge intersection point, and intersecting the trailing edge to define a trailing edge intersection point; Entrance angle β in The entrance angle β in The angle between the line parallel to the middle arc at the intersection of the leading edges and the axis of rotation is defined. Exit angle β out The exit angle β out Defined by the angle between the line parallel to the middle arc at the intersection of the trailing edges and the axis of rotation; Axial chord length (Cax) extends between the leading edge and the trailing edge in an axial direction relative to the axis of rotation; The airfoil has a contraction ratio CR greater than 0.45 along at least 80% of its span, wherein the contraction ratio CR is determined by the following formula: ； The blade rotation (BT) has less than 100 degrees along at least 30% of the span, wherein the blade rotation (BT) is determined by the following formula: ； The airfoil stiffness (S1) of the at least two airfoil elements is determined by the following formula: The airfoil stiffness (S1) is greater than or equal to 0.6 and less than or equal to 1.2 (0.6). < Sl < 1.2); and The aspect ratio (AR) of the airfoil is determined by the following formula: The aspect ratio (AR) is greater than or equal to 2 and less than or equal to 6 (2 < AR < 6).

12. The airfoil according to claim 11, characterized in that, in, The airfoil stiffness (S1) is greater than or equal to 0.7 and less than or equal to 0.9 (0.7). < Sl < 0.9).

13. The airfoil according to claim 11, characterized in that, in, The aspect ratio (AR) is greater than or equal to 3 and less than or equal to 5 (3 < AR < 5).

14. The airfoil according to claim 11, characterized in that, in, The shrinkage ratio (CR) is greater than 0.55 along at least 80% of the span.

15. The airfoil according to claim 11, characterized in that, in, The blade rotation (BT) is less than 110 degrees along the entire span.

16. The airfoil according to any one of claims 11-15, characterized in that, in, β in The span from the root to the tip is constant, or β. out The span from the root to the tip is constant.

17. The airfoil according to any one of claims 11-15, characterized in that, in, The airfoil is housed within the turbine engine.

18. The airfoil according to claim 17, characterized in that, in, The turbine engine is a counter-rotating turbine engine, and the rotor is either an inner rotor or an outer rotor.

Images