Patent Grant
11306594
The present invention generally relates to axial compressor components having an airfoil. More specifically, the present invention relates to an airfoil profile for compressor components, such as blades and/or vanes, that have a variable thickness and three-dimensional (“3D”) shape along the airfoil span in order to raise the natural frequency, improve airfoil mean stress and dynamic stress capabilities of the compressor component, and minimize risk of failure due to cracks caused by excitation of the component.
Gas turbine engines, such as those used for power generation or propulsion, include a compressor section. The compressor section includes a casing and a rotor that rotates about an axis within the casing. In axial-flow compressors, the rotor typically includes a plurality of rotor discs that rotate about the axis. A plurality of compressor blades extend away from, and are radially spaced around, an outer circumferential surface of each of the rotor discs. Typically, following each plurality of compressor blades is a plurality of compressor vanes. The plurality of compressor vanes usually extend from, and are radially spaced around, the casing. Each set of a rotor disc, a plurality of compressor blades extending from the rotor disc, and a plurality of compressor vanes immediately following the plurality of compressor blades is generally referred to as a compressor stage. The radial height of each successive compressor stage decreases because the blades and vanes increase the density, pressure and temperature of air passing through the stage. Specialized shapes of compressor blades and compressor vanes aid in compressing fluid as it passes through the compressor.
Compressor components, such as compressor blades and stator vanes, have an inherent natural frequency. When these components are excited by the passing air, as would occur during normal operating conditions of a gas turbine engine, the compressor components vibrate at different orders of engine rotational frequency. When the natural frequency of a compressor component coincides with or crosses an engine order, the compressor component can exhibit resonant vibration that in turn can cause cracking and ultimately failure of the compressor component.
This summary is intended to introduce a selection of concepts in a simplified form that are further described below in the detailed description section of this disclosure. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in isolation to determine the scope of the claimed subject matter.
In brief, and at a high level, this disclosure describes gas turbine engine components, e.g., compressor components such as blades and vanes, having airfoil portions that optimize the interaction with other compressor stages, provide for aerodynamic efficiency, and meet aeromechanical life objectives. More specifically, the compressor components described herein have unique airfoil thicknesses, chord lengths, and 3D shaping that results in the desired natural frequency of the respective compressor component. Further, the airfoil thicknesses and 3D shaping at specified radial distances along the airfoil span may provide an acceptable level of mean stress in the airfoil sections, and also provide improved blade aerodynamics and efficiency while maintaining the desired blade natural frequency. The airfoil portion of the compressor components disclosed herein, such as blades or vanes, have a particular shape or profile as specified herein. For example, one such airfoil profile may be defined by at least some of the Cartesian coordinate values of X, Y, and Z set forth in Table 1. In this example, the Z coordinate values are distances measured perpendicular to the compressor centerline and the X and Y coordinate values for each Z distance define an airfoil section when the coordinate values are connected with smooth continuing arcs. In this example, the airfoil sections at each Z distance are further joined with smooth continuing arcs to define the 3D shape of the airfoil portion of the compressor component.
The embodiments disclosed herein relate to compressor component airfoil designs and are described in detail with reference to the attached drawing figures, which illustrate non-limiting examples of the disclosed subject matter, wherein:
The subject matter of this disclosure is described herein to meet statutory requirements. However, this description is not intended to limit the scope of the invention. Rather, the claimed subject matter may be embodied in other ways, to include different steps, combinations of steps, features, and/or combinations of features, similar to those described in this disclosure, and in conjunction with other present or future technologies.
In brief, and at a high level, this disclosure describes gas turbine engine components, e.g., compressor components such as blades and vanes, having airfoil portions that may optimize the interaction with other compressor stages, provide for aerodynamic efficiency, and improve aeromechanical life objectives. More specifically, the compressor components described herein may have, in different disclosed aspects, unique airfoil thicknesses, chord lengths, and 3D shaping that results in different performance characteristics being achieved, such as, e.g., an altered natural frequency of the associated compressor component. Further, the airfoil thicknesses and 3D shaping at specified radial distances along the airfoil span may provide an acceptable level of mean stress in the airfoil sections, and also provide improved blade aerodynamics and efficiency. The airfoil portion of the compressor components disclosed herein, such as blades or vanes, have a particular shape or profile as specified herein. For example, one such airfoil profile may be defined by the Cartesian coordinate values of X, Y, and Z set forth in Table 1. In this example, the Z coordinate values are distances measured perpendicular from the compressor centerline and the X and Y coordinate values at each Z distance define an airfoil section when the coordinate values are connected with smooth continuing arcs. In this example, the airfoil sections at each Z distance may be joined with smooth continuing arcs to define the 3D shape of the airfoil portion of the compressor component.
Referring now to
One aspect of a compressor component is a compressor blade 16A, as depicted in
A compressor component may be used in a land-based compressor in connection with a land-based gas turbine engine. Typically, compressor components in such a compressor only experience temperatures below approximately 850 degrees Fahrenheit. As such, these types of compressor components may be fabricated from a relatively low temperature alloy. For example, these compressor components may be made from a stainless-steel alloy.
A cross-section of one aspect of the airfoil portion 26 is depicted in
By changing the airfoil thickness, chord, 3D shaping, and/or the distribution of material along the span of the airfoil portion 26 of the compressor component, the natural frequency of the compressor component may be altered. This may be advantageous for the operation of the compressor 10. For example, during operation of the compressor 10, the compressor component may move (e.g., vibrate) at various modes due to the geometry, temperature, and aerodynamic forces being applied to the compressor component. These modes may include bending, torsion, and various higher-order modes.
If excitation of the compressor component occurs for a prolonged period of time with a sufficiently high amplitude then the compressor component can fail due to high cycle fatigue. For example, a critical first and second bending mode for the compressor component may be 2-3 times or 6 times the 60 Hz frequency of the gas turbine engine, respectively. For this mode, the first bending mode must avoid the critical frequency ranges of 110-130 Hz and 160-200 Hz. Modifying the thickness, chord, and/or the 3D shape of the compressor component, and in particular that of the airfoil portion thereof, results in altering the natural frequency of the compressor component. Continuing with the above example, modifying the thickness, chord, and/or the 3D shape of the compressor component in accordance with the disclosure herein may result in the first bending natural frequency being increased to be between 130 and 160 Hz. This first bending natural frequency of the compressor component will therefore be between the second and third engine order excitation frequencies when the compressor is rotating at 60 Hz. More specifically, a compressor component having the thickness, chord, and/or the 3D shape as defined by the Cartesian coordinates set forth in Table 1 will have a natural frequency of first bending about halfway between 2nd and 3rd engine order excitations and second bending will be between the 5th and 6th engine order excitations, or between the 6th and 7th engine order. In other aspects, a compressor component having the thickness, chord, and/or the 3D shape as defined by the Cartesian coordinates set forth in Table 1 will have a natural frequency of first bending at least 5-10% greater than 2nd engine order excitations and at least 5-10% less than 3rd engine order excitations. In fact, a compressor component having the thickness, chord, and/or the 3D shape as defined by the Cartesian coordinates set forth in Table 1 will have a natural frequency for the lowest few vibration modes of at least 5-10% less than or greater than each engine order excitation.
In one embodiment disclosed herein, a nominal 3D shape of an airfoil portion, such as the airfoil portion 26 shown in
The coordinate values set forth in Table 1 below are for a cold condition of the compressor component (e.g., non-rotating state and at room temperature). Further, the coordinate values set forth in Table 1 below are for an uncoated nominal 3D shape of the compressor component. In some aspects, a coating (e.g., corrosion protective coating) may be applied to the compressor component. The coating thickness may be up to about 0.010 inches thick.
Further, the compressor component may be fabricated using a variety of manufacturing techniques, such as forging, casting, milling, electro-chemical machining, electric-discharge machining, and the like. As such, the compressor component may have a series of manufacturing tolerances for the position, profile, twist, and chord that can cause the compressor component to vary from the nominal 3D shape defined by the coordinate values set forth in Table 1. This manufacturing tolerance may be, for example, +/−0.120 inches in a direction away from any of the coordinate values of Table 1 without departing from the scope of the subject matter described herein. In other aspects, the manufacturing tolerances may be +/−0.080 inches. In still other aspects, the manufacturing tolerances may be +/−0.020 inches.
In addition to manufacturing tolerances affecting the overall size of the compressor component, it is also possible to scale the airfoil to a larger or smaller airfoil size. In order to maintain the benefits of this 3D shape, in terms of stiffness and stress, it is necessary to scale the compressor component uniformly in the X, Y, and Z directions. However, since the Z values in Table 1 are measured from a centerline of the compressor rather than a point on the compressor component, the scaling of the Z values must be relative to the minimum Z value in Table 1. For example, the first (i.e., radially innermost) profile section is positioned approximately 23.819 inches from the compressor centerline and the second profile section is positioned approximately 25.229 inches from the engine centerline. Thus, if the compressor component was to be scaled 20% larger, each of the X and Y values in Table 1 may simply be multiplied by 1.2. However, each of the Z values must first be adjusted to a relative scale by subtracting the distance from the compressor centerline to the first profile section (e.g., the Z coordinates for the first profile section become Z=0, the Z coordinates for the second profile section become Z=1.410 inches, etc.). This adjustment creates a nominal Z value. After this adjustment, then the nominal Z values may be multiplied by the same constant or number as were the X and Y coordinates (1.2 in this example).
The Z values set forth in Table 1 may assume a compressor sized to operate at 60 Hz. In other aspects, the compressor component described herein may also be used in different size compressors (e.g., a compressor sized to operate at 50 Hz, etc.). In these aspects, the compressor component defined by the X, Y, and Z values set forth in Table 1 may still be used, however, the Z values would be offset to account for the radial spacing of the differently sized compressors. The Z values may be offset radially inwardly or radially outwardly, depending upon whether the compressor is smaller or larger than the compressor envisioned by Table 1. For example, the rotor to which a blade is affixed may have a larger radius (e.g., 20%) than that envisioned by Table 1. In such a case, the minimum Z values (i.e., the radially innermost profile section) would be offset a distance equal to the difference in rotor radius size (e.g., the radially innermost profile section would be positioned approximately 28.583 inches from the engine centerline instead of 23.819 inches) and the remainder of the Z values would maintain their relative spacing to one another from Table 1 with the same scale factor as being applied to X and Y (e.g., if the scale factor is one then the second profile section would be positioned approximately 29.993 inches from the engine centerline—still 1.410 inches radially outward from the first profile section). Stated another way, the difference in radius of the rotor (e.g., 4.764 inches) would be added to all of the scaled Z values in Table 1.
Equation (1) provides another way to determine new Z values (e.g., scaled or translated) from the Z values listed in Table 1 when changing the relative size and/or position of the component defined by Table 1. In equation (1), Z1 is the Z value from Table 1, Z1min is the minimum Z value from Table 1, scale is the scaling factor, Z2min is the minimum Z value of the component as scaled and/or translated, and Z2 is the resultant Z value for the component as scaled and/or translated. Of note, when merely translating the component, the scaling factor in equation (1) is 1.000.
Z2=[(Z1−Z1min)*scale+Z2min] (1)
In yet another aspect, the airfoil profile may be defined by a portion of the set of X, Y, and Z coordinate values set forth in Table 1 (e.g., at least 85% of said coordinate values).
Embodiment 1. A compressor component comprising a root portion; and an airfoil portion extending from the root portion, the airfoil portion having an uncoated nominal profile substantially in accordance with Cartesian coordinate values of X, Y, and Z set forth in Table 1, wherein the X, Y, and Z coordinates are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, form an airfoil shape.
Embodiment 2. The compressor component of embodiment 1, wherein the root portion and the airfoil portion form at least part of a compressor blade.
Embodiment 3. The compressor component of any of embodiments 1-2, wherein the root portion is configured to couple with a first stage rotor disc of a compressor.
Embodiment 4. The compressor component of any of embodiments 1-3, wherein the airfoil shape lies within an envelope of +/−0.120 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 5. The compressor component of any of embodiments 1-4, wherein the airfoil shape lies within an envelope of +/−0.080 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 6. The compressor component of any of embodiments 1-5, wherein the airfoil shape lies within an envelope of +/−0.020 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 7. The compressor component of any of embodiments 1-6, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinate values listed in Table 1.
Embodiment 8. The compressor component of any of embodiments 1-7, further comprising a coating applied to the airfoil shape, the coating having a thickness of less than or equal to 0.010 inches.
Embodiment 9. A compressor blade, comprising an airfoil portion having an uncoated nominal profile substantially in accordance with Cartesian coordinate values of X, Y, and Z set forth in Table 1, wherein the X, Y, and Z coordinate values are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, define an airfoil shape.
Embodiment 10. The compressor blade of embodiment 9, wherein the X and Y coordinate values are scalable as a function of a same constant or number and a set of corresponding nominal Z coordinate values are scalable as a function of the same constant or number to provide at least one of a scaled up or a scaled down airfoil.
Embodiment 11. The compressor blade of any of embodiments 9-10, wherein the compressor blade is configured to couple with rotor discs having different sized radiuses, wherein the Z coordinate values set forth in Table 1 are offset by a distance equal to the difference in rotor disc radius to provide at least one of a radially outwardly offset or radially inwardly offset airfoil shape.
Embodiment 12. The compressor blade of any of embodiments 9-11, wherein the airfoil shape lies within an envelope of +/−0.120 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 13. The compressor blade of any of embodiments 9-12, wherein the airfoil shape provides the compressor blade with a first bending natural frequency between 130 Hz and 160 Hz when scaled for use in a compressor with a 60 Hz rotation speed.
Embodiment 14. The compressor blade of any of embodiments 9-13, wherein the airfoil shape provides the compressor blade with a second bending natural frequency that differs by at least 5% from 5th, 6th, and 7th engine order excitations.
Embodiment 15. The compressor blade of any of embodiments 9-14, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinate values listed in Table 1.
Embodiment 16. The compressor blade of any of embodiments 9-16, further comprising a coating applied to the airfoil shape, the coating having a thickness of less than or equal to 0.010 inches.
Embodiment 17. A compressor, comprising a casing; a rotor disc positioned within the casing; and a plurality of compressor blades coupled to the rotor disc, the plurality of compressor blades circumferentially spaced around the rotor disc about a center axis of the compressor, wherein each compressor blade of the plurality of compressor blades has an airfoil comprising an airfoil portion having an uncoated nominal profile substantially in accordance with Cartesian coordinate values of X, Y, and Z set forth in Table 1, wherein the X, Y, and Z coordinate values are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, define an airfoil shape.
Embodiment 18. The compressor of embodiment 17, wherein the rotor disc and the plurality of compressor blades form a compressor stage zero.
Embodiment 19. The compressor of any of embodiments 17-18, wherein the airfoil shape lies within an envelope of +/−0.120 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 20. The compressor of any of embodiments 17-19, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinate values listed in Table 1
Embodiment 21. An airfoil, comprising an airfoil profile substantially in accordance with the X, Y, and Z coordinates listed in Table 1, wherein the X, Y, and Z coordinates are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, define an airfoil shape.
Embodiment 22. The airfoil of embodiment 21, wherein the airfoil is part of a blade of a gas turbine engine.
Embodiment 23. The airfoil of any of embodiments 21-22, wherein the blade is a compressor blade.
Embodiment 24. The airfoil of any of embodiments 21-23, wherein the airfoil shape lies within an envelope of +/−0.160 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 25. The airfoil of any of embodiments 21-24, wherein the airfoil shape lies within an envelope of +/−0.080 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 26. The airfoil of any of embodiments 21-25, wherein the airfoil shape lies within an envelope of +/−0.020 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 27. The airfoil of any of embodiments 21-26, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinates listed in Table 1.
Embodiment 28. The airfoil of any of embodiments 21-27, wherein the airfoil comprises a coating.
Embodiment 29. A gas turbine engine blade, comprising an airfoil portion, comprising an airfoil profile substantially in accordance with the X, Y, and Z coordinates listed in Table 1, wherein the X, Y, and Z coordinates are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, define an airfoil shape.
Embodiment 30. The gas turbine engine blade of embodiment 29, wherein the airfoil shape defines an airfoil portion of a compressor blade.
Embodiment 31. The gas turbine engine blade of any of embodiments 29-30, wherein the gas turbine engine blade is one of a plurality of gas turbine engine blades that are assembled about an axis of a gas turbine to form an assembled gas turbine engine stage.
Embodiment 32. The gas turbine engine blade of any of embodiments 29-31, wherein the airfoil shape lies within an envelope of +/−0.160 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 33. The gas turbine engine blade of any of embodiments 29-32, wherein the airfoil shape lies within an envelope of +/−0.080 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 34. The gas turbine engine blade of any of embodiments 29-33, wherein the airfoil shape lies within an envelope of +/−0.020 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 35. The gas turbine engine blade of any of embodiments 29-34, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinates listed in Table 1.
Embodiment 36. The gas turbine engine blade of any of embodiments 29-35, wherein the airfoil comprises a coating.
Embodiment 37. A gas turbine engine, comprising a plurality of gas turbine engine blades circumferentially assembled about a center axis of the gas turbine engine, wherein at least one of the plurality of gas turbine engine blades has an airfoil comprising an airfoil profile substantially in accordance with the X, Y, and Z coordinates listed in Table 1, wherein the X, Y, and Z coordinates are distances in inches measured in a Cartesian coordinate system, wherein, at each Z distance, the corresponding X and Y coordinates, when connected by a smooth continuous arc, define one of a plurality of airfoil profile sections, and wherein the plurality of airfoil profile sections, when joined together by smooth continuous arcs, define an airfoil shape.
Embodiment 38. The gas turbine engine of embodiment 37, wherein the plurality of gas turbine engine blades form an assembled compressor stage.
Embodiment 39. The gas turbine engine of any of embodiments 37-38, wherein the airfoil shape lies within an envelope of +/−0.160 inches measured in a direction normal to any of the plurality of airfoil profile sections.
Embodiment 40. The gas turbine engine of any of embodiments 37-39, wherein the airfoil profile is in accordance with at least 85% of the X, Y, and Z coordinates listed in Table 1.
Embodiment 41. Any of the aforementioned embodiments 1-40, in any combination.
The subject matter of this disclosure has been described in relation to particular embodiments, which are intended in all respects to be illustrative rather than restrictive. Alternative embodiments will become apparent to those of ordinary skill in the art to which the present subject matter pertains without departing from the scope hereof. Different combinations of elements, as well as use of elements not shown, are also possible and contemplated.
| Number | Name | Date | Kind |
|---|---|---|---|
| 7517190 | Latimer | Apr 2009 | B2 |
| 7540715 | Latimer | Jun 2009 | B2 |
| 8057188 | Parker et al. | Nov 2011 | B2 |
| 8113773 | Hudson et al. | Feb 2012 | B2 |
| 8192168 | Bonini et al. | Jun 2012 | B2 |
| 8556588 | Shrum et al. | Oct 2013 | B2 |
| 8591193 | Kathika et al. | Nov 2013 | B2 |
| 9523284 | Miller et al. | Dec 2016 | B2 |
| 9890790 | Miller et al. | Feb 2018 | B2 |
| 10801327 | Song | Oct 2020 | B2 |
