A high-temperature turbine disc cavity sealing structure based on multi-wing centrifugal blades and a turbine

Abstract

The application relates to the field of turbine technology and provides a high-temperature turbine disc cavity sealing structure based on a multi-wing centrifugal blade and a turbine. The sealing structure comprises at least: a turbine guide vane disc rear wall surface; a turbine moving vane disc front wall surface; a space between the turbine guide vane disc rear wall surface and the turbine moving vane disc front wall surface forms a sealing flow channel suitable for sealing gas flow; and a plurality of multi-wing centrifugal blades are arranged at intervals along the circumferential direction of the turbine moving vane disc front wall surface. When the turbine impeller disc rotates at high speed, the sealing gas in the turbine disc cavity is pushed by the multi-wing centrifugal blade to move along the sealing flow channel to the outer edge direction of the turbine disc cavity, so that the high-temperature combustion gas is prevented from invading into the turbine disc cavity through the sealing flow channel, the sealing effect is improved by increasing the flow rate of the sealing gas without increasing the sealing gas, and the turbine aerodynamic performance is prevented from being affected by the mixing of the excessive sealing cold gas into the main flow channel and the main flow.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of turbine technology, in particular to a high-temperature turbine disc cavity sealing structure based on multi-wing centrifugal blades and a turbine. BACKGROUND

[0002] In recent years, turbines using gas working medium pressure energy and heat energy are widely used in various structures, providing power for industrial production and people's life. According to the Carnot theorem, in order to make the unit volume of turbine equipment have higher energy conversion rate, the inlet temperature of the turbine needs to be increased. However, in the actual operation process, due to the high pressure of the high-temperature gas in the main flow channel, a part of the high-temperature gas will invade the turbine disc cavity under the action of pressure difference, and will form ablation to the high-speed rotating impeller disc, which seriously affects the safety of operation, so it is an important way to improve the safety of turbine operation to control the invasion of high-temperature gas working medium into the turbine disc cavity by using appropriate technical means.

[0003] At present, there are many technical methods to control the invasion of gas into the disc cavity, including various types of rim sealing structures and cooling gas jet, etc. The basic principle of the above-mentioned methods is to increase the flow resistance of high-temperature gas invading the disc cavity, and at the same time, to inhibit the invasion of gas by spraying cold gas from the disc cavity to the turbine main channel, so as to prevent the safety problem caused by overheating of the turbine disc. However, in the prior art, when controlling the invasion of gas into the disc cavity, the sealing of cold gas through the complex rim sealing gap causes insufficient sealing capacity, and the structure of high-temperature gas contacting the disc causes overheating problem. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is that in the prior art, when controlling the invasion of gas into the disc cavity, the sealing of cold gas through the complex rim sealing gap causes insufficient sealing capacity, and the structure of high-temperature gas contacting the disc causes overheating problem, so as to provide a high-temperature turbine disc cavity sealing structure based on multi-wing centrifugal blades and a turbine.

[0005] To solve the above technical problems, the technical scheme of the present application is as follows:

[0006] A high-temperature turbine disc cavity sealing structure based on multi-wing centrifugal blades, at least comprising: a turbine guide vane disc rear wall surface; a turbine moving blade disc front wall surface, and the space between the turbine guide vane disc rear wall surface and the turbine moving blade disc front wall surface forms a sealing flow channel suitable for sealing gas flow; a plurality of multi-wing centrifugal blades are arranged along the circumferential direction of the turbine moving blade disc front wall surface, and the multi-wing centrifugal blades are suitable for pushing the sealing gas in the turbine disc cavity to move along the sealing flow channel to the outer edge direction of the turbine disc cavity when the impeller disc of the turbine rotates at high speed, so as to limit the invasion of high-temperature gas into the turbine disc cavity through the sealing flow channel.

[0007] Further, the camber line form of the multi-wing centrifugal blade comprises one or more of single circular arc, segmented circular arc and cubic B-spline.

[0008] Further, the cross-sectional shape of the multi-wing centrifugal blade comprises NACA airfoil and / or Clark airfoil.

[0009] Further, the sealing flow passage is gradually tapered along the flow direction of the sealing gas.

[0010] Further, the through-flow cross-sectional shape of the sealing flow passage comprises one or more of straight-line tapered cross-section, circular arc tapered cross-section and spline curve tapered cross-section.

[0011] Further, the cross-sectional inlet radius of the sealing flow passage is consistent with the inlet radius of the multi-wing centrifugal blade; the cross-sectional outlet radius of the sealing flow passage is consistent with the outlet radius of the multi-wing centrifugal blade; and the cross-sectional shape of the sealing flow passage is consistent with the change in blade height of the multi-wing centrifugal blade.

[0012] A turbine comprising the multi-wing centrifugal blade-based high-temperature turbine disc cavity sealing structure of any one of the above.

[0013] Further, the type of the turbine comprises one or more of axial flow, mixed flow, single-stage structure and multi-stage structure.

[0014] Further, the source of high-temperature working medium of the turbine comprises one or more of atmospheric environment, engine exhaust gas, fuel gas, industrial exhaust flue gas, compressed air, solar collector high-temperature gas, heat accumulator high-temperature gas and chemical process high-temperature gas.

[0015] The technical scheme of the present application has the following advantages:

[0016] The multi-wing centrifugal blade-based high-temperature turbine disc cavity sealing structure provided by the present application comprises a multi-wing centrifugal blade arranged on the front wall of the turbine rotor disc. When the turbine rotor disc rotates at high speed, the multi-wing centrifugal blade pushes the sealing gas in the turbine disc cavity to move along the sealing flow passage towards the outer edge of the turbine disc cavity, thereby limiting the high-temperature combustion gas from entering the turbine disc cavity through the sealing flow passage and avoiding the problem of overheating caused by the contact between the high-temperature combustion gas and the rotor disc structure. Moreover, without increasing the amount of sealing gas, the sealing effect is improved by increasing the flow rate of the sealing gas, thereby avoiding the influence on the turbine aerodynamic performance caused by the excessive sealing cold gas entering the main flow passage and mixing with the main flow. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the specific embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings described below are some embodiments of the present application, and all other drawings obtained by those of ordinary skill in the art without creative labor based on these drawings also belong to the protection scope of the present application.

[0018] Figure 1 A schematic diagram of the multi-wing centrifugal blade based high-temperature turbine disc cavity sealing structure in the embodiments of the present application;

[0019] Figure 2 A schematic diagram of the multi-wing centrifugal blade in the Figure 1

[0020] Figure 3 A schematic diagram of the sealing flow channel in the Figure 1

[0021] A schematic diagram of the sealing flow channel in the Figure 4 Figure 3 A schematic diagram of the A part of one embodiment in the

[0022] Figure 5 A schematic diagram of the A part of another embodiment in the Figure 3

[0023] A schematic diagram of the A part of another embodiment in the Figure 6 Figure 3 A schematic diagram of the A part of another embodiment in the

[0024] Reference signs:

[0025] 1, moving blade; 2, moving blade hub; 3, multi-wing centrifugal blade; 4, turbine guide vane disc rear wall surface; 5, turbine moving blade disc front wall surface; 6, sealing flow channel; 7, impeller rotation shaft; 8, guide vane; 9, sealing gas; 10, high-temperature gas working medium. EMBODIMENT

[0026] The technical solutions of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor also belong to the protection scope of the present application.

[0027] ​​​In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, 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 invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0030] Figure 1 This is a schematic diagram of a high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades in an embodiment of the present invention; Figure 2 for Figure 1 A schematic diagram of the multi-bladed centrifugal blades in the centrifuge. Figure 3 for Figure 1 A schematic diagram of the sealed flow channel; as shown in the diagram. Figure 1 , Figure 2 as well as Figure 3 As shown, this embodiment provides a high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades 3, comprising at least: a turbine guide vane disk rear wall surface 4; a turbine impeller disk front wall surface 5, the space between which forms a sealing flow channel 6 suitable for the flow of sealing gas 9; and multi-bladed centrifugal blades 3, with a plurality of multi-bladed centrifugal blades 3 spaced apart along the circumferential direction of the turbine impeller disk front wall surface 5. The multi-bladed centrifugal blades 3 are adapted to push the sealing gas 9 in the turbine disk cavity to move along the sealing flow channel 6 towards the outer edge of the turbine disk cavity when the turbine impeller disk rotates at high speed, thereby restricting the intrusion of high-temperature combustion gas into the turbine disk cavity through the sealing flow channel 6. The number of blades, the inlet radius R1 and outlet radius R2 of the multi-bladed centrifugal blades 3, the inlet and outlet airflow angles, and the blade arc length can be determined according to the actual geometric dimensions and operating conditions.

[0031] The high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades 3 provided in this embodiment uses multi-bladed centrifugal blades 3 on the front wall 5 of the turbine impeller disk. When the turbine impeller disk rotates at high speed, the multi-bladed centrifugal blades 3 push the sealing gas 9 in the turbine disk cavity to move along the sealing flow channel 6 towards the outer edge of the turbine disk cavity, thereby restricting the intrusion of high-temperature gas into the turbine disk cavity through the sealing flow channel 6 and avoiding overheating caused by the high-temperature gas contacting the disk structure. Moreover, without increasing the sealing gas 9, the sealing effect is improved by increasing the flow rate of the sealing gas 9, avoiding the impact on the turbine aerodynamic performance caused by excessive sealing cold gas entering the turbine mainstream flow channel and mixing with the mainstream.

[0032] Among them, the mid-arc shape of the multi-wing centrifugal blade 3 includes one or more of the following: single circular arc, segmented circular arc, and cubic B-spline.

[0033] The cross-sectional shape of the multi-bladed centrifugal blade 3 includes NACA airfoil and / or Clark airfoil.

[0034] In this configuration, the sealing channel 6 gradually contracts along the flow direction of the sealing gas 9. This arrangement, through the blowing effect of the multi-bladed centrifugal blades 3, promotes the entry of the low-temperature sealing gas 9 into the mainstream, prevents the high-temperature mainstream gas from entering the disk cavity space, reduces the temperature of the rear wall surface 4 of the turbine guide vane disk and the front wall surface 5 of the turbine impeller disk, prevents the aforementioned walls from burning out, and achieves the purpose of protecting the turbine structure.

[0035] Figure 4 for Figure 3 An enlarged schematic diagram of part A in one embodiment; Figure 5 for Figure 3 An enlarged schematic diagram of part A in another embodiment; Figure 6 for Figure 3 Another enlarged schematic diagram of part A in an embodiment; as shown Figure 4 , Figure 5 as well as Figure 6 As shown, the flow cross-sectional shape of the sealed flow channel 6 includes a straight-line contracting cross-section ( Figure 4 ), circular arc-shaped contraction section ( Figure 5 ) and spline curve type contraction section ( Figure 6 One or more of the following. This configuration can further accelerate the sealing cooling gas and prevent the high-temperature mainstream from intruding into the wheel cavity.

[0036] Among them, the inlet radius of the sealed flow channel 6 is consistent with the inlet radius of the multi-bladed centrifugal blade 3; the outlet radius of the sealed flow channel 6 is consistent with the outlet radius of the multi-bladed centrifugal blade 3; and the cross-sectional shape of the sealed flow channel 6 is consistent with the blade height variation of the multi-bladed centrifugal blade 3.

[0037] Another embodiment provides a turbine comprising the high-temperature turbine disk cavity sealing structure based on the multi-wing centrifugal blade 3 of any one of the above. Wherein, the turbine further comprises a moving blade 1, a moving blade hub 2, a wheel rotating shaft 7 and a guide vane 8; wherein the moving blade 1 is arranged on the moving blade hub 2, the guide vane 8 is installed on the turbine guide vane disk, and the moving blade hub 2 and the turbine disk connected thereto can rotate around the wheel rotating shaft 7. In operation, the high-temperature gas working medium 10 first enters the guide vane, is accelerated in the guide vane 8, and then enters the wheel, and when flowing through the moving blade 1, the wheel disk is driven to rotate to do work. Wherein, the source of the high-temperature gas working medium 10 of the turbine includes atmospheric environment, engine exhaust gas, fuel gas, industrial exhaust flue gas, compressed air, solar collector high-temperature gas, heat accumulator high-temperature gas, and chemical process high-temperature gas.

[0038] Wherein, the type of the turbine includes one or more of axial flow, mixed flow, single-stage structure and multi-stage structure. Wherein, the number of turbines, geometric shape and structural size, and rotating speed can be determined according to overall thermodynamic design parameters. In summary, the high-temperature turbine disk cavity sealing structure based on the multi-wing centrifugal blade and the turbine in the present application can effectively inhibit the invasion of high-temperature gas and ensure the operation safety and service life of the high-temperature turbine under the condition of ensuring the constant amount of sealing gas, based on the principle of increasing gas kinetic energy based on the rotation of the multi-wing centrifugal fan wheel.

[0039] The high-temperature turbine disk cavity sealing structure based on the multi-wing centrifugal blade and the turbine in the present application can be optimized according to the actual operation conditions and conditions of the high-temperature turbine, so it can be applied to high-temperature turbines operating under different conditions.

[0040] Obviously, the above embodiments are only examples for clear illustration, and are not limitations on the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades, characterized in that, At least including: Rear wall of the turbine guide vane disk; The space between the front wall of the turbine impeller disk and the rear wall of the turbine guide vane disk forms a sealing flow channel suitable for the flow of sealing gas; The multi-bladed centrifugal blades are arranged at intervals along the circumferential direction of the front wall of the turbine impeller disk. The multi-bladed centrifugal blades are adapted to push the sealing gas in the turbine disk cavity to move along the sealing flow channel towards the outer edge of the turbine disk cavity when the turbine impeller disk rotates at high speed, so as to restrict the high temperature gas from entering the turbine disk cavity through the sealing flow channel. The sealing channel gradually narrows along the flow direction of the sealing gas; The flow cross-sectional shape of the sealed flow channel includes one of the following: a straight contraction section, a circular arc contraction section, and a spline curve contraction section; The inlet radius of the sealed flow channel is the same as the inlet radius of the multi-bladed centrifugal blade; The cross-sectional outlet radius of the sealed flow channel is the same as the outlet radius of the multi-bladed centrifugal blade; The cross-sectional shape of the sealed flow channel is consistent with the change in blade height of the multi-bladed centrifugal blade.

2. The high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades according to claim 1, characterized in that, The mid-arc shape of the multi-bladed centrifugal blades includes one of the following: single circular arc, segmented circular arc, and cubic B-spline.

3. The high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades according to claim 1, characterized in that, The cross-sectional shape of the multi-bladed centrifugal blades includes NACA airfoil or Clark airfoil.

4. A turbine, characterized in that, The high-temperature turbine disk cavity sealing structure based on multi-bladed centrifugal blades, as described in any one of claims 1-3.

5. The turbine according to claim 4, characterized in that, The turbine type includes one of axial flow, mixed flow, single-stage, or multi-stage structures.

6. The turbine according to claim 5, characterized in that, The high-temperature working fluid source of the turbine includes one or more of the following: atmospheric environment, engine exhaust gas, fuel gas, industrial emission flue gas, compressed air, and high-temperature gas from solar collectors.

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