Turbine rotor blade and gas turbine engine
By setting a multi-layer rib and baffle structure at the tip of the turbine rotor blades, the problem of high-pressure gas leakage at the blade tip was solved, the turbine's work capacity was improved, and the mixing loss of the leaked fluid was reduced.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2022-05-25
- Publication Date
- 2026-04-14
AI Technical Summary
Existing turbine rotor blades suffer from high-pressure gas leakage at the blade tip under the action of high-temperature combustion gas, which reduces the turbine's work capacity.
A multi-layer structure is formed at the tip of the turbine rotor blade, consisting of a leading edge rib, a trailing edge rib, a suction side rib, a pressure side rib, a first diaphragm, and a second diaphragm, to block and guide leakage flow and increase the air seal effect.
It effectively reduces the leakage of high-pressure gas at the blade tip, improves the turbine's work capacity, and reduces the mixing loss of leaked fluid with the mainstream.
Smart Images
Figure CN117167093B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aero engines, and more particularly to a turbine rotor blade and a gas turbine engine. Background Technology
[0002] A turbine typically consists of guide vanes, rotor blades, a turbine casing for fixing the guide vanes, and a turbine rotor for fixing the rotor blades. High-temperature combustion gas flows in from the guide vane inlet, expands and accelerates within the contraction channel between the guide vanes, and flows at a certain angle to the rotor blades downstream of the guide vanes. This creates a region with lower velocity and higher static pressure on one side of the rotor blades, called the pressure side; and a region with higher velocity and lower static pressure on the other side, called the suction side. Under the pressure difference between the pressure and suction sides of the rotor blades, the rotor blades rotate at high speed around the turbine's central axis, driving the compressor connected to the other end of the turbine shaft to perform work. Because the rotor blades are constantly rotating at high speed during operation, while the turbine casing (or the outer ring fixedly connected to the turbine casing) that encloses the rotor blades remains stationary, a certain clearance must exist between the rotor blades and the turbine casing (or outer ring) to ensure that the high-speed rotating rotor blades do not scrape against the stationary parts under different stress deformations, vibrations, etc., which could lead to destructive consequences.
[0003] As the high-temperature combustion gas flows out of the guide vane outlet and drives the rotor blades to perform work, some of the gas leaks through the blade tip gaps from the pressure side of the moving blade to the suction side. This portion of the gas does not contribute to driving the moving blades to perform work, thus reducing the overall work capacity of the turbine. For example... Figure 1 A schematic diagram of an existing rotor blade is shown. Existing research shows that a double-ribbed blade tip structure 91 is provided at the blade tip 90 of the rotor blade, which increases the resistance of the gas flow from the pressure side to the suction side of the blade tip, thereby reducing the leakage flow at the blade tip.
[0004] Currently, reducing the leakage of high-pressure gas at the tips of rotor blades has been a long-standing area of focus for those skilled in the art. Summary of the Invention
[0005] The purpose of this invention is to provide a turbine rotor blade that can effectively reduce the leakage of high-pressure gas at the blade tip.
[0006] The turbine rotor blade for achieving the aforementioned purpose includes: [a component] disposed at the tip of the turbine rotor blade.
[0007] The leading edge rib of the blade tip extends from the beginning of the leading edge to the end of the leading edge.
[0008] The leaf tip trailing edge rib extends from the beginning of the trailing edge to the end of the trailing edge.
[0009] The suction surface side rib extends from the starting position of the leading edge to the starting position of the trailing edge along the airfoil profile on the suction surface side of the turbine rotor blade at the blade tip.
[0010] The blade tip pressure surface side rib extends along the airfoil profile of the turbine rotor blade at the blade tip, from the starting position on the pressure surface side to the ending position on the trailing edge, and an opening is formed between the starting position on the pressure surface side and the ending position on the leading edge, the axial length of the opening being less than 0.05 times the axial chord length.
[0011] The first partition includes the following components connected in sequence:
[0012] The first segment is arc-shaped, extending from the termination position of the leading edge toward the middle arc line of the turbine rotor blade, and terminating at the intersection with the middle arc line;
[0013] The second segment extends along the central arc towards the trailing edge, terminating at 50% of the turbine rotor blade.
[0014] Up to 60% of the axial chord length; and
[0015] The third segment, in an arc shape, extends from the termination position of the second segment toward the tip pressure surface side rib, intersects with the tip pressure surface side rib, and terminates at the turbine rotor blade 65.
[0016] % to 75% of the axial chord length; and
[0017] The second baffle extends from the first baffle at a position of 8% to 12% of the axial chord length of the turbine rotor blade to the suction side rib at the blade tip.
[0018] In one or more embodiments, the turbine rotor blades have a tip suction side leakage flow at the blade tip, and the extension direction of the second baffle is perpendicular to the direction of the tip suction side leakage flow.
[0019] In one or more embodiments, the height direction of the first partition is parallel to the radial direction of the turbine rotor blade.
[0020] In one or more embodiments, the first baffle is inclined toward the tip pressure surface side rib such that there is an angle between the height direction of the first baffle and the radial direction of the turbine rotor blade between 20 and 30 degrees.
[0021] In one or more embodiments, the height direction of the second partition is parallel to the radial direction of the turbine rotor blade.
[0022] In one or more embodiments, the second septum is inclined toward the leading edge such that there is an angle between the height direction of the second septum and the radial direction of the turbine rotor blades, which is between 20 and 30 degrees.
[0023] In one or more embodiments, the tangential direction of the first segment forms an angle between 90 and 120 degrees with the tangential direction of the leading edge rib of the blade tip.
[0024] In one or more embodiments, the third segment intersects with the tip pressure surface side rib and terminates at 70% of the axial chord length of the turbine rotor blade.
[0025] In one or more embodiments, the second partition begins in the first partition at 10% of the axial chord length of the turbine rotor blade.
[0026] On the other hand, according to some embodiments of this application, a gas turbine engine is also provided, which includes the aforementioned turbine rotor blades.
[0027] The beneficial effects of this invention are as follows:
[0028] In this turbine rotor blade, the first baffle plays two roles in controlling the leakage flow flowing in from the blade tip pressure side: Firstly, it guides the leakage fluid flowing downstream from upstream. Since the upstream leakage flow has a higher pressure, it increases the pressure within the first chamber, effectively sealing the downstream leakage flow. Secondly, it prevents the pressure-side leakage flow from flowing directly out from above the blade tip suction side rib. Simultaneously, a slot is cut into the blade tip pressure side rib near the starting position of the first baffle, forming an opening that allows some high-pressure fluid to flow into the first chamber, further enhancing the aforementioned sealing effect. Furthermore, the second baffle blocks the suction-side leakage flow. Simultaneously, the enclosed second chamber causes the leakage flow (with relatively high pressure) flowing in from the blade tip leading edge (pressure side, suction side) to stagnate within the second chamber, creating localized high pressure and providing a sealing effect against axial leakage.
[0029] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description
[0030] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0031] Figure 1 A schematic diagram of existing rotor blades is shown;
[0032] Figure 2 A schematic diagram of tip leakage flow and blade surface pressure distribution with a double-ribbed tip structure is shown.
[0033] Figure 3 A perspective view of turbine rotor blades according to some embodiments of this application is shown;
[0034] Figure 4 A top view schematic diagram of a turbine rotor blade according to some embodiments of this application is shown;
[0035] Figure 5 as well as Figure 6 A schematic diagram of the tip of a turbine rotor blade according to some embodiments of this application is shown;
[0036] Figure 7 A statistical diagram of tip leakage flow rate of a turbine rotor blade according to some embodiments of this application is shown;
[0037] Figure 8 A schematic diagram of a first partition according to some embodiments of this application is shown;
[0038] Figure 9 A schematic diagram of a first partition according to other embodiments of this application is shown. Detailed Implementation
[0039] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.
[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0041] To further and effectively reduce the leakage of high-pressure combustion gas at the rotor blade tips, the inventors discovered that the fluid flow state entering the tip gap from different positions on the blade varies due to the pressure distribution on the blade surface. Figure 2The diagram illustrates the tip leakage flow and blade surface pressure distribution of a blade with a double-ribbed tip structure. Fluid a, which enters from the suction side of the blade leading edge, flows directly back into the mainstream from downstream of the suction side under the influence of the pressure difference on the suction side. Fluid b, which enters from the pressure side of the blade leading edge, flows downstream first within the groove formed by the double-ribbed tip structure, and then merges into the mainstream from the suction side. Fluid c, which enters from 50% axial position or later on the pressure side of the blade, is affected by a large lateral pressure difference and flows directly across the tip groove and out from the suction side.
[0042] Based on the above characteristics, the applicant discovered that the problems existing in the prior art can be solved by providing a turbine rotor blade with a new configuration.
[0043] On the one hand, according to some embodiments of this application, a turbine rotor blade is provided, such as... Figure 3 A perspective view of turbine rotor blades according to some embodiments of this application is shown. Figure 4 A top view schematic diagram of turbine rotor blades according to some embodiments of this application is shown. Figure 5 as well as Figure 6 A schematic diagram of the tip of a turbine rotor blade according to some embodiments of this application is shown.
[0044] The turbine rotor blade has a blade body 100, a blade root 200, and a blade tip 300. The direction from the blade root 200 to the blade tip 300 is the radial direction e of the turbine rotor blade. The turbine rotor blade also has a leading edge 400 and a trailing edge 500. The leading edge 400 is arc-shaped, with a leading edge start position 401 and a leading edge end position 402. The midpoint of the arc of the leading edge 400 is the leading edge point 403 of the turbine rotor blade. The trailing edge 500 is also arc-shaped, with a trailing edge start position 501 and a trailing edge end position 502. The midpoint of the arc of the trailing edge 500 is the trailing edge point 503 of the turbine rotor blade. When installed in a turbine, the turbine's axial direction is the turbine rotor blade's axial direction f, which is also the airflow direction in the turbine. The turbine rotor blade has a chord length along the axial direction f; that is, it has 0% of the axial chord length at the leading edge point 403 and 100% of the axial chord length at the trailing edge point 503. In addition, the turbine rotor blades also have a suction side 600, i.e., the blade back side; and a pressure side 700, i.e., the blade basin side.
[0045] It is understood that the starting and ending positions described in the text are merely descriptions of the relative positions of the associated objects, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0046] Please continue reading Figures 3 to 5According to some embodiments of this application, the turbine rotor blade includes a leading edge rib 1, a trailing edge rib 2, a suction side rib 3, a pressure side rib 4, a first septum 5, and a second septum 6 disposed at the blade tip 300.
[0047] Among them, the blade tip leading edge rib 1 and the blade tip trailing edge rib 2 extend along the leading edge arc and trailing edge arc of the turbine rotor blade at the blade tip 300, respectively. Specifically, the blade tip leading edge rib 1 extends from the starting position 401 of the leading edge to the ending position 402 of the leading edge, and the blade tip trailing edge rib 2 extends from the starting position 501 of the trailing edge to the ending position 502 of the trailing edge.
[0048] The suction surface side rib 3 extends from the leading edge starting position 401 to the trailing edge starting position 501 along the airfoil profile of the suction surface side 600 of the turbine rotor blade on the blade tip 300.
[0049] The tip pressure surface side rib 4 extends from the starting position 41 to the trailing edge termination position 502 along the airfoil profile of the turbine rotor blade pressure surface side 700 on the blade tip 300. An opening 40 is formed between the starting position 41 and the trailing edge termination position 402. The axial length of the opening 40 is less than 0.05 times the axial chord length, that is, the length of the opening 40 along the axial direction f is less than 0.05 times the overall axial chord length of the turbine rotor blade.
[0050] The first diaphragm 5 includes a first segment 51, a second segment 52, and a third segment 53 connected in sequence. The first segment 51 is arc-shaped and extends from the leading edge termination position 402 along the extension direction of the arc towards the middle arc line g of the turbine rotor blade, terminating at the intersection with the middle arc line g. The second segment 52 extends along the extension direction of the middle arc line g towards the trailing edge 500 and terminates at 50% to 60% of the axial chord length of the turbine rotor blade. The third segment 53 is also arc-shaped and extends from the termination position of the second segment 52 towards the tip pressure surface side rib 4, terminating after intersecting with the tip pressure surface side rib 4, with the termination position located at 65% to 75% of the axial chord length of the turbine rotor blade.
[0051] The second diaphragm 6 extends from the first diaphragm 5. The starting position of the second diaphragm 6 is located on the first diaphragm 5 at 8% to 12% of the axial chord length of the turbine rotor blade, and extends to the suction side rib 3 at the blade tip, terminating at the intersection.
[0052] Understandably, the leading edge rib 1, trailing edge rib 2, suction side rib 3, pressure side rib 4, first diaphragm 5, and second diaphragm 6 protrude from the tip 300 of the turbine rotor blade, thus forming a first chamber 21 between the trailing edge rib 2 and the first diaphragm 5, and a second chamber 22 between at least a portion of the first diaphragm 5, second diaphragm 6, leading edge rib 1, and suction side rib 3. The first diaphragm 5 serves two purposes for the leakage flow flowing in from the pressure side of the tip: firstly, it guides the leakage fluid flowing downstream from upstream, increasing the pressure within the first chamber 21 due to the higher pressure of the upstream leakage flow, thus acting as an air seal for the downstream leakage flow; secondly, it prevents the pressure side leakage flow from flowing directly out from above the suction side rib 3. Meanwhile, near the starting position of the first partition 5, a groove is made on the blade tip pressure side rib 4 to form an opening 40, allowing some high-pressure fluid to flow into the first chamber 21, thus increasing the aforementioned air seal effect.
[0053] The second baffle 6 blocks the leakage flow on the suction side. At the same time, the enclosed second chamber 22 causes the leakage flow (with relatively high pressure) flowing in from the leading edge of the blade tip (pressure side, suction side) to stagnate in the second chamber 22, forming a local high pressure and creating an air seal effect on the axial leakage flow.
[0054] Figure 7 The following diagram illustrates the tip leakage flow statistics of turbine rotor blades according to some embodiments of this application, such as... Figure 7 As shown, the starting point of the leakage flow mixing with the mainstream is closer to the blade trailing edge, which helps reduce the mixing loss between the leakage fluid and the mainstream. Based on CFD calculations, the tip leakage flow rate can be reduced by 3%.
[0055] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary and secondary relationship of the indicated technical features.
[0056] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0057] Furthermore, according to some embodiments of this application, the turbine rotor blades have a tip suction side leakage flow at the blade tip, for example... Figure 2In the fluid a, the extension direction of the second baffle 6 is perpendicular to the direction of the leakage flow on the blade tip suction side. That is, the second baffle 6 extends between the first baffle 5 and the blade tip suction side rib 3 in a direction perpendicular to the leakage flow on the blade tip suction side.
[0058] Furthermore, according to some embodiments of this application, the first septum 5 protrudes along the height direction h at the blade tip 300. For example... Figure 8 A schematic diagram of a first partition 5 according to some embodiments of this application is shown, wherein the height direction h of the first partition 5 is parallel to the radial direction e of the turbine rotor blades, i.e., the first partition 5 is a straight plate. Figure 9 A schematic diagram of a first baffle 5 according to other embodiments of this application is shown, wherein the first baffle 5 is inclined toward the tip pressure surface side rib 4, such that there is an angle x1 between the height direction h of the first baffle 5 and the radial direction e of the turbine rotor blade, the angle x1 being between 20 degrees and 30 degrees, i.e., the first baffle 5 is an inclined plate. The inclined plate form of the first baffle 5 further effectively limits leakage flow.
[0059] Similarly, according to some embodiments of this application, the second diaphragm 6 also protrudes along its height direction at the blade tip 300. In one specific embodiment, the height direction of the second diaphragm 6 is parallel to the radial direction e of the turbine rotor blade; that is, in this embodiment, the second diaphragm 6 is a straight plate. In another specific embodiment, the second diaphragm 6 is inclined towards the leading edge 400, such that there is an angle between the height direction of the second diaphragm 6 and the radial direction of the turbine rotor blade, that is, in this embodiment, the second diaphragm 6 is an inclined plate. The inclined plate form of the second diaphragm 6 further effectively limits leakage flow.
[0060] Furthermore, according to some embodiments of this application, please refer to... Figure 6 The tangent direction of the first segment 51, which is in the shape of an arc, has an angle x2 with the tangent direction of the leading edge rib 1, which is in the shape of an arc. The angle x2 is between 90 degrees and 120 degrees. By setting the aforementioned structure, the turbine rotor blade is easier to cast and demold in this embodiment.
[0061] According to some embodiments of this application, preferably, the third segment 53 intersects with the tip pressure surface side rib 4 and terminates at 70% of the axial chord length of the turbine rotor blade.
[0062] According to some embodiments of this application, preferably, the second partition 52 begins in the first partition 51 at 10% of the axial chord length of the turbine rotor blade.
[0063] On the other hand, according to some embodiments of this application, a gas turbine engine is also provided, which includes turbine rotor blades as described in the preceding one or more embodiments.
[0064] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. A turbine rotor blade, characterized in that, Including those located at the tips of the turbine rotor blades: The leading edge rib of the blade tip extends from the beginning of the leading edge to the end of the leading edge. The leaf tip trailing edge rib extends from the beginning of the trailing edge to the end of the trailing edge. The suction surface side rib extends from the starting position of the leading edge to the starting position of the trailing edge along the airfoil profile on the suction surface side of the turbine rotor blade at the blade tip. The blade tip pressure surface side rib extends along the airfoil profile of the turbine rotor blade at the blade tip, from the starting position on the pressure surface side to the ending position on the trailing edge, and an opening is formed between the starting position on the pressure surface side and the ending position on the leading edge, the axial length of the opening being less than 0.05 times the axial chord length. The first partition includes the following components connected in sequence: The first segment is arc-shaped, extending from the termination position of the leading edge toward the middle arc line of the turbine rotor blade, and terminating at the intersection with the middle arc line; The second segment extends along the central arc towards the trailing edge and terminates at 50% to 60% of the axial chord length of the turbine rotor blade. as well as The third segment is arc-shaped and extends from the end position of the second segment toward the tip pressure surface side rib, intersecting with the tip pressure surface side rib and terminating at 65% to 75% of the axial chord length of the turbine rotor blade. as well as The second baffle extends from the first baffle at a position of 8% to 12% of the axial chord length of the turbine rotor blade to the suction side rib at the blade tip.
2. The turbine rotor blade as described in claim 1, characterized in that, The turbine rotor blades have a suction-side leakage flow at the blade tip, and the extension direction of the second baffle is perpendicular to the direction of the suction-side leakage flow.
3. The turbine rotor blade as described in claim 1, characterized in that, The height direction of the first partition is parallel to the radial direction of the turbine rotor blade.
4. The turbine rotor blade as described in claim 1, characterized in that, The first baffle is inclined toward the blade tip pressure surface side rib so that there is an angle between the height direction of the first baffle and the radial direction of the turbine rotor blade between 20 and 30 degrees.
5. The turbine rotor blade as described in claim 1, characterized in that, The height direction of the second partition is parallel to the radial direction of the turbine rotor blade.
6. The turbine rotor blade as described in claim 1, characterized in that, The second septum is inclined toward the leading edge so that there is an angle between the height direction of the second septum and the radial direction of the turbine rotor blades, which is between 20 and 30 degrees.
7. The turbine rotor blade as claimed in claim 1, characterized in that, The tangential direction of the first segment forms an angle between 90 and 120 degrees with the tangential direction of the leading edge rib of the blade tip.
8. The turbine rotor blade as claimed in claim 1, characterized in that, The third segment intersects with the blade tip pressure surface side rib and terminates at 70% of the axial chord length of the turbine rotor blade.
9. The turbine rotor blade as claimed in claim 1, characterized in that, The second baffle begins in the first baffle at 10% of the axial chord length of the turbine rotor blade.
10. A gas turbine engine, characterized in that, Includes turbine rotor blades as described in any one of claims 1 to 9.
Citation Information
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