A gas turbine with a balanced axial force structure

Abstract

The present invention discloses a gas turbine with a balanced axial force structure, comprising a rotating shaft, a compressor, a turbine and a combustion chamber; a nose cone is provided on the rotating shaft, the nose cone is located on the side of the compressor away from the turbine, and the side of the nose cone facing away from the compressor has a nose cone thrust surface; a thrust seat is provided on the side of the nose cone facing away from the compressor, the thrust seat has a seat body surface arranged opposite to the nose cone thrust surface, and a nose cone gap is provided between the seat body surface and the nose cone thrust surface; the thrust seat is provided with an axially through first air supply hole, the air inlet of the first air supply hole is connected to the air source, the air outlet of the first air supply hole is connected to the nose cone gap, and the air source supplies air to the nose cone gap through the first air supply hole to form thrust on the nose cone. The gas turbine with a balanced axial force structure of the present invention forms axial thrust on the nose cone, thrust plate and turbine by additionally providing air supply holes at the nose cone, thrust bearing or turbine, thereby assisting in balancing the axial force of the gas turbine and enabling the gas turbine to operate stably.

Description

Technical Field

[0001] The invention relates to a gas turbine with a balanced axial force structure, belonging to the technical field of gas turbines. Background Art

[0002] The gas turbine uses a continuously flowing gas as a working fluid to drive the impeller to rotate at high speed, converting the energy of the fuel into useful work. It is a rotating impeller heat engine. It mainly includes three parts: the compressor, the combustion chamber, and the turbine: the compressor inhales air from the external atmosphere and compresses it step by step to increase the pressure, and the air temperature is also increased accordingly; the compressed air is sent to the combustion chamber to mix with the injected fuel and burn to generate high-temperature and high-pressure gas; then it enters the turbine to expand and do work, driving the turbine to drive the compressor and the external load rotor to rotate at high speed, which can realize the partial conversion of the chemical energy of the gas or liquid fuel into mechanical work and heat energy, and can output electrical energy by connecting to a generator.

[0003] During the operation of the gas turbine, the airflow will exert an axial force on the rotor blades and the impeller, thereby generating an axial force. In order to prevent the rotor from moving axially, the thrust bearing will bear the axial force from the gas turbine rotor. From gas dynamics, it can be seen that the axial force on the gas turbine compressor rotor is forward, while the axial force on the turbine rotor is backward. Under maximum operating conditions, the turbine rotor on the gas turbine generator needs to withstand a backward axial force, while the compressor rotor needs to withstand a larger forward axial force. Even if the two opposite axial forces on the rotor offset each other partially after the compressor rotor and the turbine rotor are connected as one, it is still a forward axial force of considerable value. Therefore, it is necessary to set a load reduction device to reduce the axial load of the rotor on the thrust bearing. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention provides a gas turbine with a balanced axial force structure. The present invention assists in balancing the axial force of the gas turbine by additionally providing air supply holes at the nose cone, thrust bearing or turbine.

[0005] The present invention is achieved through the following technical solutions:

[0006] A gas turbine with a balanced axial force structure comprises a rotating shaft, a compressor, a turbine and a combustion chamber, wherein the compressor and the turbine are both sleeved and mounted on the rotating shaft; the exhaust end of the compressor is connected to the inlet end of the combustion chamber; the outlet end of the combustion chamber is connected to the inlet end of the turbine;

[0007] A nose cone is provided on the rotating shaft, and the nose cone is located on the side of the compressor away from the turbine, and the side of the nose cone facing away from the compressor is provided with a nose cone thrust surface; a thrust seat is also provided on the side of the nose cone facing away from the compressor, and the thrust seat has a seat body surface arranged opposite to the thrust surface of the nose cone, and a nose cone gap is provided between the seat body surface and the thrust surface of the nose cone; a first axially penetrating air supply hole is provided in the radial center area of ​​the thrust seat, the air inlet of the first air supply hole is connected with the air source, and the air outlet of the first air supply hole is connected with the nose cone gap, and the air source can supply air to the nose cone gap through the first air supply hole to form thrust on the nose cone.

[0008] Furthermore, the gas turbine further comprises a bearing assembly, wherein the bearing assembly comprises at least one gas thrust bearing and a thrust plate. The gas thrust bearing is selected from a static pressure bearing, a dynamic pressure bearing and / or a static and dynamic mixed bearing.

[0009] Furthermore, the gas thrust bearing has an air inlet hole, the air inlet of the air inlet hole is connected to the gas source, the air outlet of the air inlet hole faces the thrust plate, and the cross-sectional area of ​​the first air supplement hole is larger than the cross-sectional area of ​​the air inlet hole of the gas thrust bearing (the cross section refers to the cross section perpendicular to the extension direction of the hole, for example, when the first air supplement hole and the air inlet hole are both circular holes, the aperture of the first air supplement hole is larger than the aperture of the air inlet hole). The first air supplement hole with a larger aperture can provide sufficient gas flow, and thus can provide sufficient thrust to balance the axial force of the gas turbine rotor.

[0010] Furthermore, the air inlet hole may be a straight hole or a stepped hole with a decreasing cross-sectional area. The stepped hole may further increase the velocity of the incoming airflow, even reaching or exceeding the speed of sound, so as to further enhance the thrust.

[0011] Furthermore, the number of the air inlet holes may be one or more; when the number is more than one, the air inlet holes may be arranged around the axis, for example, evenly arranged.

[0012] Furthermore, there are multiple (more than two, including two) gas thrust bearings, wherein a second air-filling hole is provided on the gas thrust bearing on the same side of the thrust disc and the nose cone, the air inlet of the second air-filling hole is connected to the air source, the air outlet of the second air-filling hole faces the thrust disc, and the cross-sectional area of ​​the second air-filling hole is larger than the cross-sectional area of ​​the air inlet and air outlet of the gas thrust bearing. The second air-filling hole can further increase the thrust at the thrust disc, thereby being more conducive to providing sufficient thrust to balance the axial force of the gas turbine rotor.

[0013] Furthermore, the number of the second air supplementing holes may be one or more. When the number is more than one, the second air supplementing holes may be arranged around the axis, for example, evenly arranged.

[0014] Furthermore, the arrangement of the air inlet and the second air supplementary hole can be arranged around the rotor axis, or the air inlet can be arranged around the second air supplementary hole. For example, in a gas thrust bearing provided with a second air supplementary hole, multiple air inlet holes are arranged in multiple circles around the rotating shaft, and the number of second air supplementary holes is multiple and located between two adjacent circles of air inlet holes (the air inlet holes are reused as air seals). For another example, in a gas thrust bearing provided with a second air supplementary hole, the second air supplementary holes are arranged around the rotating shaft, and multiple air inlet holes are arranged around each second air supplementary hole.

[0015] Furthermore, the thrust bearing may also have an air groove for evenly distributing air intake, the air inlet of the air intake hole is opened at the bottom of the air groove, and the air inlet of the second air supplement hole is opened on the boss of the air groove. Such an arrangement can prevent the air from each route from interfering with each other before being ejected from the outlet.

[0016] Furthermore, the second air supply hole can be arranged at an angle, with the air inlet of the second air supply hole being relatively far away from the rotating shaft, and the air outlet of the second air supply hole being relatively toward the rotating shaft.

[0017] Furthermore, the nose cone has an air groove, the bottom surface of the air groove is the thrust surface of the nose cone, and an air cavity capable of accommodating a certain amount of gas is formed between the air groove and the seat body surface of the thrust seat, which can seal part of the gas to slow down the rate of gas overflowing from the edge, thereby ensuring the thrust effect. The air groove can be one or more. The shape of the air groove can be circular, elliptical, rectangular, etc.

[0018] Furthermore, the thrust seat has a plurality of first air sealing holes arranged around the first air supplement hole; the air outlet of the first air sealing hole faces the thrust surface of the nose cone, the cross-sectional area of ​​the first air sealing hole is smaller than the cross-sectional area of ​​the first air supplement hole, and the air from the air source can be sprayed toward the nose cone through the first air sealing hole to form an air curtain around the first air supplement hole. The number of the first air sealing holes can be one or more; when there are more than one, the plurality of first air sealing holes are arranged around the first air supplement hole.

[0019] Furthermore, the first air sealing hole can be a straight hole or a stepped hole with a decreasing cross-sectional area. The stepped hole can further increase the incoming air flow velocity, even reaching or exceeding the speed of sound, so as to further enhance the barrier effect of the air curtain.

[0020] Furthermore, a guide vane assembly is provided at the outlet end of the combustion chamber for guiding the high-temperature gas discharged from the outlet end of the combustion chamber into the turbine, and a turbine thrust component is provided between the guide vane assembly and the turbine; a third air supply hole is provided on the turbine thrust component, an air inlet of the third air supply hole is connected to an air source, and an air outlet of the third air supply hole faces the turbine, and the gas from the air source can be sprayed toward the turbine through the third air supply hole, thereby forming an axial thrust on the turbine, which is beneficial to balancing the axial force and ensuring stable operation of the gas turbine.

[0021] Further, the number of the third air supplement holes may be one or more; when there are more than one, the third air supplement holes may be arranged around the axis.

[0022] Furthermore, the turbine thrust component is generally annular and is arranged around the rotating shaft. The turbine thrust component is airtightly connected to the guide vane assembly, and an air sealing effect can be formed between the turbine thrust component and the turbine (the turbine thrust component also serves as an air sealing component); a second air sealing hole is provided on the turbine thrust component, an air inlet of the second air sealing hole is connected to an air source, an air outlet of the second air sealing hole faces the turbine, and the turbine has a receiving surface corresponding to the second air sealing hole; the cross-sectional area of ​​the second air sealing hole is smaller than the cross-sectional area of ​​the third air supply hole.

[0023] Furthermore, the number of the second air-sealing holes may be one or more; when the number is more than one, the second air-sealing holes may be arranged around the axis, for example, evenly arranged.

[0024] Furthermore, the second air-sealing holes and the third air-supplementing holes may be arranged around the rotor axis, or the second air-sealing holes may be arranged around the third air-supplementing holes, for example: multiple second air-sealing holes are arranged around the rotating shaft in multiple circles, and the number of third air-supplementing holes is multiple and located between two adjacent circles of second air-sealing holes. For another example: the third air-supplementing holes are arranged around the rotating shaft, and multiple second air-supplementing holes surround each third air-supplementing hole.

[0025] Furthermore, the second air sealing hole can be a straight hole or a stepped hole with a decreasing cross-sectional area. The stepped hole can further increase the incoming air flow velocity, even reaching or exceeding the speed of sound, so as to further enhance the barrier effect of the pressure air curtain.

[0026] Furthermore, the receiving surface of the turbine facing the second air sealing hole has a groove corresponding to the airflow injected from the second air sealing hole. The airflow injected from the second air sealing hole flows back toward the turbine thrust component through the groove, thereby enhancing the pressure air curtain effect.

[0027] Furthermore, the turbine thrust component has a toothed portion on the side facing the turbine to form a tooth seal with the turbine to further enhance the gas sealing effect. The toothed portion can be a high-low tooth structure, a flat tooth structure, an oblique flat tooth structure, a side tooth structure, etc.

[0028] Furthermore, the turbine may have a convex edge corresponding to the toothed portion, and the convex edge has a protrusion or tooth structure matching the toothed portion to improve the gas sealing effect of the toothed portion. Furthermore, the turbine has a groove on one side facing the turbine thrust component, and part of the turbine thrust component extends into the groove.

[0029] Furthermore, the guide vane assembly comprises a first support, a second support and a blade group with an axial air passage located between the two supports, and the turbine thrust component is airtightly connected to the first support. During the operation of the gas turbine, the turbine can rotate relative to the combustion chamber and the guide vane assembly.

[0030] Furthermore, the gas source for supplying air to the first air supply hole, the air inlet hole, the second air supply hole, the third air supply hole, the first air sealing hole, and the second air sealing hole can be an external air pump (capable of providing air of different pressures and flows to suit different working conditions) or an air compressor (capable of saving the cost of setting up an additional external air source).

[0031] Furthermore, the nose cone can be provided independently of the limiting nut of the compressor (the limiting nut is used to fix the compressor on the rotating shaft), or it can be provided integrally with the limiting nut of the compressor to also serve as a limiting function.

[0032] Furthermore, the air inlet of the compressor may be opened on the side of the gas turbine casing, which is a lateral air intake.

[0033] Furthermore, the combustion chamber is arranged around the rotating shaft and is installed on the bearing seat assembly corresponding to the turbine end.

[0034] The gas turbine with a balanced axial force structure of the present invention assists in balancing the axial force of the gas turbine by additionally providing air supply holes (first air supply hole, second air supply hole, third air supply hole) at the nose cone, thrust bearing or turbine. The working principle is as follows: the air source supplies air to the gap between the seat body surface and the thrust surface of the nose cone through the first air supply hole to form thrust on the nose cone. Since the first air supply hole is opened in the central area, the air flow ejected from the first air supply hole can provide sufficient thrust to the head before overflowing from the edge, thereby balancing the axial force of the gas turbine rotor. The air source blows the air flow to the thrust disk through the second air supply hole, which can further increase the thrust at the thrust disk, thereby being more conducive to providing sufficient thrust to balance the axial force of the gas turbine rotor. The air source blows the air flow to the turbine through the third air supply hole, forming an axial thrust on the turbine, which is conducive to balancing the axial force and making the gas turbine run stably.

[0035] When the gas bearing mentioned in this article is a hydrostatic bearing, it has the following structure: it includes a bearing body and a bearing sleeve nested from the outside to the inside, the bearing sleeve and the rotating shaft have a predetermined radial clearance in the radial direction (when the bearing is a radial bearing), or the bearing sleeve and the thrust plate are installed opposite to each other in the axial direction of the rotating shaft and have a predetermined axial clearance (when the bearing is a thrust bearing); an annular air cavity is provided on the outer circumference of the bearing sleeve, and a through hole is provided on the bearing sleeve that passes through the annular air cavity and the gap (radial gap or axial gap); an air hole is provided on the bearing body that connects the annular air cavity with an external air source; in order to facilitate processing and not affect the gas pressure in the gap, the through hole can be a variable diameter hole, that is, the diameter of the through hole is larger on the side away from the gap, and the diameter is smaller on the side close to the gap.

[0036] When the gas bearing mentioned in this article is a hydrodynamic bearing, it has the following structure: it includes a bearing body, the bearing body and the rotating shaft have a predetermined radial clearance in the radial direction (when the bearing is a radial bearing), and a dynamic pressure generating groove is provided on the inner diameter surface of the bearing body or the portion of the rotating shaft where the bearing body is installed; or: the bearing body and the thrust plate are installed opposite to each other in the axial direction of the rotating shaft and have a predetermined axial clearance (when the bearing is a thrust bearing), and a dynamic pressure generating groove is provided on the end surface of the bearing body facing the thrust plate or the end surface of the thrust plate facing the bearing body.

[0037] When the gas bearing mentioned in this article is a static-dynamic mixed bearing, its structure has the characteristics of both a static-dynamic bearing and a dynamic-dynamic bearing. The present invention will not be described in detail.

[0038] The various terms and phrases used in the present invention have the general meanings known to those skilled in the art. If the terms and phrases mentioned are inconsistent with the commonly known meanings, the meanings expressed in the present invention shall prevail. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 : Schematic diagram of the structure of a gas turbine (Example 1).

[0040] Figure 2 : Schematic diagram of the structure of the first thrust bearing (Example 1).

[0041] Figure 3 : Schematic diagram of the structure of the head cone.

[0042] Figure 4 : Schematic diagram of the structure of the nose cone and thrust seat.

[0043] Figure 5 : Schematic diagram of the structure of a gas turbine (Example 2).

[0044] Figure 6 : Schematic diagram of the structure of the first thrust bearing (Example 2).

[0045] Figure 7 : Schematic diagram of the structure of the first thrust bearing with air grooves (Example 2).

[0046] Figure 8 : Schematic diagram of the structure of the first thrust bearing (Example 2) (the second air supply hole is set obliquely).

[0047] Fig. 9 : Schematic diagram of the structure of the gas turbine (Example 3).

[0048] Fig.10 : Schematic diagram of the structure of the turbine thrust component.

[0049] Fig.11: Schematic diagram of the structure of the turbine thrust component (with a second air sealing hole).

[0050] Fig.12 : Schematic diagram of the structure of the turbine thrust component (with a second gas sealing hole and a toothed portion).

[0051] Among them, 100, rotating shaft; 200, compressor; 300, turbine; 400, combustion chamber; 500, bearing assembly; 510, first radial bearing; 520, second radial bearing; 530, first thrust bearing; 540, second thrust bearing; 531, air inlet hole; 532, second air supply hole; 600, bearing seat assembly; 700, nose cone; 710, nose cone thrust surface; 720, air groove; 800, thrust seat; 810, first air supply hole; 820, first air sealing hole; 900, turbine thrust component; 910, third air supply hole; 920, second air sealing hole; 930, toothed portion. DETAILED DESCRIPTION

[0052] The present invention will be further described below in conjunction with the embodiments. However, the scope of the present invention is not limited to the following embodiments. It will be appreciated by those skilled in the art that various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention.

[0053] Example 1 Gas turbine with balanced axial force structure

[0054] A gas turbine with a balanced axial force structure includes a rotating shaft 100, a compressor 200, a turbine 300 and a combustion chamber 400. Figure 1 As shown, the compressor 200 and the turbine 300 are both sleeved and mounted on the rotating shaft 100; the exhaust end of the compressor 200 is connected to the inlet end of the combustion chamber 500; the outlet end of the combustion chamber 400 is connected to the inlet end of the turbine 300;

[0055] The rotating shaft 100 is provided with a nose cone 700, which is located at a side of the compressor 200 away from the turbine 300, and a side of the nose cone 700 facing away from the compressor 200 has a nose cone thrust surface 710; the side of the nose cone 700 facing away from the compressor 200 is also provided with a thrust seat 800, and the thrust seat 800 has a seat body surface arranged opposite to the nose cone thrust surface 710, and a nose cone gap is provided between the seat body surface and the nose cone thrust surface; the radial center area of ​​the thrust seat 800 is provided with a nose cone thrust surface 710; An axially through-going first air supply hole 810 is provided, the air inlet of the first air supply hole 810 is connected to the air source, the air outlet of the first air supply hole 810 is connected to the nose cone gap, the air source can supply air to the nose cone gap through the first air supply hole 810 to form a thrust on the nose cone 700. Since the first air supply hole 810 is opened in the central area, the airflow ejected from the first air supply hole 810 can provide sufficient thrust to the nose cone 700 before overflowing from the edge, thereby balancing the axial force of the gas turbine rotor.

[0056] The gas turbine further includes a bearing assembly 500 and a bearing seat assembly 600 , wherein the bearing assembly 500 is located within the bearing seat assembly 600 ; the bearing assembly 500 includes a first radial bearing 510 , a second radial bearing 520 , a first thrust bearing 530 , a second thrust bearing 540 , and a thrust plate, wherein the thrust plate is located between the first thrust bearing 530 and the second thrust bearing 540 .

[0057] The first thrust bearing 530 is a gas bearing having an air inlet hole 531. Figure 2 As shown, the air inlet of the air inlet hole 531 is connected to the air source, the air outlet of the air inlet hole 531 faces the thrust plate, and the cross-sectional area of ​​the first air supplement hole 810 is larger than the cross-sectional area of ​​the air inlet hole 531 (the cross-sectional area refers to the cross-sectional area perpendicular to the extension direction of the hole, for example, when the first air supplement hole 810 and the air inlet hole 531 are both circular holes, the aperture of the first air supplement hole is larger than the aperture of the air inlet hole). Usually, in order to stabilize the bearing air film and ensure the pressure stability of the air source, the cross-sectional area of ​​the air inlet hole of the gas bearing is often not very large, and it is even set to a throttling hole shape, so the air supply is limited, which limits the thrust it can provide (about 200 to 300 Newtons). By setting the first air supplement hole 810 with a larger aperture, sufficient gas flow can be provided, and then sufficient thrust can be provided to balance the axial force of the gas turbine rotor.

[0058] The air inlet hole 531 may be a straight through hole or a stepped hole with a decreasing cross-sectional area. The stepped hole may further increase the velocity of the incoming airflow, even reaching or exceeding the speed of sound, so as to further enhance the thrust.

[0059] The number of the air inlet hole 531 may be one or more. When the number is more than one, the air inlet holes 531 may be arranged around the axis, for example, evenly arranged.

[0060] The gas source for supplying gas to the first gas replenishment hole 810 and the gas inlet hole 531 can be an external air pump (capable of providing gas of different pressures and flows to suit different working conditions) or a compressor 200 (capable of saving the cost of setting up an additional external gas source).

[0061] The nose cone 700 may also have an air groove 720, the bottom surface of the air groove 720 being the nose cone thrust surface 710. Figure 3 As shown, an air cavity capable of accommodating a certain amount of gas is formed between the air groove 720 and the seat surface of the thrust seat 800, which can seal part of the gas to slow down the rate at which the gas overflows from the edge, thereby ensuring the thrust effect. The air groove 720 can be one or more. The shape of the air groove 720 can be circular, elliptical, rectangular, etc.

[0062] The thrust seat 800 may also have a plurality of first air sealing holes 820 arranged around the first air supply hole 810, such as Figure 4 As shown, the air outlet of the first air sealing hole 820 faces the nose cone thrust surface 710 of the nose cone 700, and the cross-sectional area of ​​the first air sealing hole 820 is smaller than the cross-sectional area of ​​the first air supplement hole 810; the air from the air source can be sprayed toward the nose cone 700 (for example, the nose cone thrust surface 710) through the first air sealing hole 820 to form an air curtain around the first air supplement hole 810. After the air curtain is formed, the thrust provided at the nose cone 700 can reach 1800 Newtons; due to the obstruction of the formed air curtain, the gas that will overflow from the edge of the first air supplement hole 810 will be dispersed into multiple small air flows, and due to the disturbance and friction of the air flow in the air curtain, these small air flows form stronger vortices, the speed is reduced, and the kinetic energy consumption is converted into heat energy, thereby achieving the purpose of preventing or reducing leakage. The number of the first air sealing holes 820 can be one or more; when there are multiple first air sealing holes 820, multiple first air sealing holes 820 are arranged around the first air supplement hole 810.

[0063] The first air sealing hole 820 may be a straight through hole or a stepped hole with a cross-sectional area from large to small (eg Figure 4 As shown in the figure, from the air inlet to the air outlet, the cross-sectional area decreases from large to small), the stepped holes can further increase the incoming air flow velocity, even reaching or exceeding the speed of sound, so as to further enhance the barrier effect of the air curtain.

[0064] The nose cone 700 can be provided independently of the limiting nut of the compressor 200 (the limiting nut is used to fix the compressor on the rotating shaft), or it can be provided integrally with the limiting nut of the compressor 200 to also serve as a limiting function.

[0065] The air inlet of the compressor 200 may be opened on the side of the gas turbine casing, which is a side air intake.

[0066] The combustion chamber 400 is disposed around the rotating shaft 100 and is mounted on the bearing seat assembly 600 corresponding to the end of the turbine 300 .

[0067] The rotating shaft, compressor, turbine, bearing seat assembly and thrust seat are integrally installed in the housing ( Figure 1 Only part of the housing is shown).

[0068] Example 2 Gas turbine with balanced axial force structure

[0069] A gas turbine with a balanced axial force structure includes a rotating shaft 100, a compressor 200, a turbine 300 and a combustion chamber 400. Figure 1 As shown, the compressor 200 and the turbine 300 are both sleeved and mounted on the rotating shaft 100; the exhaust end of the compressor 200 is connected to the inlet end of the combustion chamber 500; the outlet end of the combustion chamber 400 is connected to the inlet end of the turbine 300;

[0070] The rotating shaft 100 is provided with a nose cone 700, which is located at a side of the compressor 200 away from the turbine 300, and a side of the nose cone 700 facing away from the compressor 200 has a nose cone thrust surface 710; the side of the nose cone 700 facing away from the compressor 200 is also provided with a thrust seat 800, and the thrust seat 800 has a seat body surface arranged opposite to the nose cone thrust surface 710, and a nose cone gap is provided between the seat body surface and the nose cone thrust surface; the radial center area of ​​the thrust seat 800 is provided with a nose cone thrust surface 710; An axially through-going first air supply hole 810 is provided, the air inlet of the first air supply hole 810 is connected to the air source, the air outlet of the first air supply hole 810 is connected to the nose cone gap, the air source can supply air to the nose cone gap through the first air supply hole 810 to form a thrust on the nose cone 700. Since the first air supply hole 810 is opened in the central area, the airflow ejected from the first air supply hole 810 can provide sufficient thrust to the nose cone 700 before overflowing from the edge, thereby balancing the axial force of the gas turbine rotor.

[0071] The gas turbine further includes a bearing assembly 500 and a bearing seat assembly 600 , wherein the bearing assembly 500 is located within the bearing seat assembly 600 ; the bearing assembly 500 includes a first radial bearing 510 , a second radial bearing 520 , a first thrust bearing 530 , a second thrust bearing 540 , and a thrust plate, wherein the thrust plate is located between the first thrust bearing 530 and the second thrust bearing 540 .

[0072] The first thrust bearing 530 (the thrust bearing on the same side of the thrust plate and the nose cone 700) is provided with an air inlet hole 531 and a second air supply hole 532. Figure 5 , Figure 6 As shown, the air inlet of the air inlet hole 531 is connected to the air source, and the air outlet of the air inlet hole 531 faces the thrust plate, the air inlet of the second air supplement hole 532 is connected to the air source, and the air outlet of the second air supplement hole 532 faces the thrust plate; the cross-sectional area of ​​the first air supplement hole 810 is larger than the cross-sectional area of ​​the air inlet hole 531, and the cross-sectional area of ​​the second air supplement hole 532 is larger than the cross-sectional area of ​​the air outlet of the air inlet hole 531. The second air supplement hole 532 is provided to further increase the thrust at the thrust plate, thereby being more conducive to providing sufficient thrust to balance the axial force of the gas turbine rotor.

[0073] The number of the second air supplementing holes 532 may be one or more. When the number is more than one, the second air supplementing holes 532 may be arranged around the axis, for example, evenly arranged.

[0074] The arrangement of the air inlet holes 531 and the second air supplement holes 532 can be arranged around the axis of the rotor 100, or the air inlet holes 531 can be arranged around the second air supplement holes 532. For example, multiple air inlet holes 531 are arranged in multiple circles around the rotating shaft, and the number of second air supplement holes 532 is multiple and located between two adjacent circles of air inlet holes 531 (the air inlet holes are reused as air seals). For another example, the second air supplement holes 532 are arranged around the rotating shaft, and multiple air inlet holes 531 are surrounded by each second air supplement hole 532.

[0075] The first thrust bearing 530 may also have an air groove 533 for evenly distributing air intake. Figure 7 As shown, the air inlet of the air inlet hole 531 is opened at the bottom of the air groove 533, and the air inlet of the second air supplement hole 532 is opened on the boss 534 of the air groove 533. This arrangement can prevent the gases from interfering with each other before being ejected from the outlet.

[0076] The second air supply hole 532 can be arranged tilted, the air inlet of the second air supply hole 532 is relatively far away from the rotating shaft 100, and the air outlet of the second air supply hole 532 is relatively toward the rotating shaft 100. Figure 8 shown.

[0077] The gas source for supplying air to the first air supply hole 810, the air inlet hole 531, and the second air supply hole 532 can be an external air pump (capable of providing air of different pressures and flows to suit different working conditions) or a compressor 200 (capable of saving the cost of setting up an additional external air source).

[0078] Example 3 Gas turbine with balanced axial force structure

[0079] A gas turbine with a balanced axial force structure includes a rotating shaft 100, a compressor 200, a turbine 300 and a combustion chamber 400. Figure 1 As shown, the compressor 200 and the turbine 300 are both sleeved and mounted on the rotating shaft 100; the exhaust end of the compressor 200 is connected to the inlet end of the combustion chamber 500; the outlet end of the combustion chamber 400 is connected to the inlet end of the turbine 300;

[0080] The rotating shaft 100 is provided with a nose cone 700, which is located at a side of the compressor 200 away from the turbine 300, and a side of the nose cone 700 facing away from the compressor 200 has a nose cone thrust surface 710; the side of the nose cone 700 facing away from the compressor 200 is also provided with a thrust seat 800, and the thrust seat 800 has a seat body surface arranged opposite to the nose cone thrust surface 710, and a nose cone gap is provided between the seat body surface and the nose cone thrust surface; the radial center area of ​​the thrust seat 800 is provided with a nose cone thrust surface 710; An axially through-going first air supply hole 810 is provided, the air inlet of the first air supply hole 810 is connected to the air source, the air outlet of the first air supply hole 810 is connected to the nose cone gap, the air source can supply air to the nose cone gap through the first air supply hole 810 to form a thrust on the nose cone 700. Since the first air supply hole 810 is opened in the central area, the airflow ejected from the first air supply hole 810 can provide sufficient thrust to the nose cone 700 before overflowing from the edge, thereby balancing the axial force of the gas turbine rotor.

[0081] The gas turbine further includes a bearing assembly 500 and a bearing seat assembly 600 , wherein the bearing assembly 500 is located within the bearing seat assembly 600 ; the bearing assembly 500 includes a first radial bearing 510 , a second radial bearing 520 , a first thrust bearing 530 , a second thrust bearing 540 , and a thrust plate, wherein the thrust plate is located between the first thrust bearing 530 and the second thrust bearing 540 .

[0082] The first thrust bearing 530 is a gas bearing having an air inlet hole 531. Figure 2 As shown, the air inlet of the air inlet hole 531 is connected to the air source, the air outlet of the air inlet hole 531 faces the thrust plate, and the cross-sectional area of ​​the first air supplement hole 810 is larger than the cross-sectional area of ​​the air inlet hole 531. By providing the first air supplement hole 810 with a larger aperture, sufficient gas flow can be provided, and thus sufficient thrust can be provided to balance the axial force of the gas turbine rotor.

[0083] The air inlet hole 531 may be a straight through hole or a stepped hole with a decreasing cross-sectional area. The stepped hole may further increase the velocity of the incoming airflow, even reaching or exceeding the speed of sound, so as to further enhance the thrust.

[0084] The number of the air inlet hole 531 may be one or more. When the number is more than one, the air inlet holes 531 may be arranged around the axis, for example, evenly arranged.

[0085] The outlet end of the combustion chamber 400 is provided with a guide vane assembly for guiding the high temperature gas discharged from the outlet end of the combustion chamber 300 into the turbine. A turbine thrust component 900 is provided between the guide vane assembly and the turbine 300. Fig. 9 As shown; the turbine thrust component 900 is provided with a third air supply hole 910, such as Fig.10As shown, the air inlet of the third air supply hole 910 is connected to the air source, and the air outlet of the third air supply hole 910 faces the turbine. The air from the air source can be sprayed toward the turbine through the third air supply hole 910, forming an axial thrust on the turbine, which is beneficial to balancing the axial force and making the gas turbine run stably.

[0086] The number of the third air supplement holes 910 may be one or more. When there are more than one third air supplement holes 910 , the third air supplement holes 910 may be arranged around the axis.

[0087] The turbine thrust component 900 is generally annular and is arranged around the rotating shaft 100. The turbine thrust component 900 is airtightly connected to the guide vane assembly, and an air seal effect can be formed between the turbine thrust component 900 and the turbine 300 (the turbine thrust component 900 also serves as an air seal component); a second air seal hole 920 is provided on the turbine thrust component 900, such as Fig.11 As shown, the air inlet of the second air sealing hole 920 is connected to the air source, and the air outlet of the second air sealing hole 920 faces the turbine 300. The air from the air source can be sprayed toward the turbine 300 through the second air sealing hole 920. The turbine 300 has a receiving surface corresponding to the second air sealing hole 920. The cross-sectional area of ​​the second air sealing hole 920 is smaller than the cross-sectional area of ​​the third air supplement hole 910. The air sprayed from the second air sealing hole 920 to the turbine 300 can form a pressure air curtain, which can block the gas sprayed from the guide vane assembly to the blades of the turbine 300 from entering the gas turbine. The air flow velocity sprayed from the second air sealing hole 920 is relatively high (especially after throttling through the stepped hole), and the air from the turbine 300 is guided by the high-speed air flow (in fact, there will also be a certain amount of air flow in the cavity near the rotating shaft 100, part of which comes from the air outlet end of the gas bearing, and the other part comes from the cooling air introduced from the compressor outlet), so that the air flow velocity on both sides of the air curtain is increased and the pressure is reduced, so as to minimize the pressure difference on both sides of the air curtain and achieve a good air sealing effect.

[0088] The number of the second air-sealing holes 920 may be one or more. When the number is more than one, the second air-sealing holes 920 may be arranged around the axis, for example, evenly arranged.

[0089] The second air-sealing holes 920 and the third air-supplementing holes 910 may be arranged around the rotor axis, or the second air-sealing holes 920 may be arranged around the third air-supplementing holes 910. For example, multiple second air-sealing holes 920 are arranged around the rotating shaft in multiple circles, and the number of third air-supplementing holes 910 is multiple and located between two adjacent circles of second air-sealing holes 920. For another example, the third air-supplementing holes 910 are arranged around the rotating shaft, and multiple second air-supplementing holes 920 surround each third air-supplementing hole 910.

[0090] The second air-sealing hole 920 may be a straight through hole or a stepped hole with a cross-sectional area from large to small (eg Fig.11As shown in the figure, from the air inlet to the air outlet, the cross-sectional area decreases from large to small), the stepped holes can further increase the incoming air flow velocity, even reaching or exceeding the speed of sound, so as to further enhance the barrier effect of the pressure air curtain.

[0091] The gas source for supplying air to the first air supply hole 810, the air inlet hole 531, the third air supply hole 910, and the second air sealing hole 920 can be an external air pump (capable of providing air of different pressures and flows to suit different working conditions) or a compressor 200 (capable of saving the cost of setting up an additional external air source).

[0092] The receiving surface of the turbine 300 facing the second air sealing hole 920 has a groove corresponding to the airflow ejected from the second air sealing hole 920. The airflow ejected from the second air sealing hole 920 flows back toward the turbine thrust component 900 through the groove, thereby enhancing the pressure air curtain effect.

[0093] The turbine thrust component 900 may have a toothed portion 930 on the side facing the turbine 300 to form a tooth seal with the turbine to further enhance the gas sealing effect. Fig.12 The toothed portion 930 may be a high-low tooth structure, a flat tooth structure, an oblique flat tooth structure, a side tooth structure, etc.

[0094] The turbine 300 may have a convex edge corresponding to the toothed portion 930, and the convex edge has a protrusion or tooth structure matching the toothed portion 930 to improve the air sealing effect of the toothed portion 930. Specifically, the turbine 300 has a groove on one side facing the turbine thrust component 900, and part of the turbine thrust component 900 extends into the groove.

[0095] The guide vane assembly includes a first support, a second support and a blade group with an axial air passage located between the two supports, and the turbine thrust component 900 is airtightly connected to the first support. During the operation of the gas turbine, the turbine 300 can rotate relative to the combustion chamber 400 and the guide vane assembly.

[0096] The above examples are provided to those skilled in the art to fully disclose and describe how to make and use the claimed embodiments, and are not intended to limit the scope of the disclosure herein. Modifications that are obvious to those skilled in the art will fall within the scope of the appended claims.

[0097] Although the above describes the specific implementation methods of the present invention in combination with the embodiments, it is not intended to limit the scope of protection of the present invention. Technical personnel in the relevant field should understand that various modifications or variations that can be made by technical personnel in the field without creative work on the basis of the technical solution of the present invention are still within the scope of protection of the present invention.

Claims

1. A gas turbine with a balanced axial force structure, characterized in that: It includes a rotating shaft, a compressor, a turbine and a combustion chamber, wherein the compressor and the turbine are both sleeved and mounted on the rotating shaft; the exhaust end of the compressor is connected to the inlet end of the combustion chamber; the outlet end of the combustion chamber is connected to the inlet end of the turbine; A nose cone is provided on the rotating shaft, and the nose cone is located on a side of the compressor away from the turbine, and a side of the nose cone facing away from the compressor has a nose cone thrust surface; a thrust seat is also provided on the side of the nose cone facing away from the compressor, and the thrust seat has a seat body surface arranged opposite to the thrust surface of the nose cone, and a nose cone gap is provided between the seat body surface and the thrust surface of the nose cone; a first axially penetrating air supply hole is provided in the radial center area of ​​the thrust seat, an air inlet of the first air supply hole is connected to an air source, an air outlet of the first air supply hole is connected to the nose cone gap, and the air source supplies air to the nose cone gap through the first air supply hole to form thrust on the nose cone; The gas turbine further comprises a bearing assembly, wherein the bearing assembly comprises at least one gas thrust bearing and a thrust plate; The cross-sectional area of ​​the first air supply hole is larger than the cross-sectional area of ​​the air inlet hole of the gas thrust bearing; The nose cone has an air groove, the bottom surface of the air groove is the thrust surface of the nose cone, and an air cavity is formed between the air groove and the seat body surface of the thrust seat; The thrust seat is provided with a plurality of first air sealing holes arranged around the first air supplement hole; the air outlets of the first air sealing holes face the thrust surface of the nose cone, and the cross-sectional area of ​​the first air sealing holes is smaller than the cross-sectional area of ​​the first air supplement hole; A guide vane assembly is provided at the outlet end of the combustion chamber, and a turbine thrust component is provided between the guide vane assembly and the turbine; a third air supply hole is provided on the turbine thrust component, an air inlet of the third air supply hole is connected to an air source, an air outlet of the third air supply hole faces the turbine, and air from the air source is sprayed toward the turbine through the third air supply hole, thereby forming an axial thrust on the turbine.

2. The gas turbine with a balanced axial force structure according to claim 1, characterized in that: There are multiple gas thrust bearings, wherein a second air supply hole is provided on the gas thrust bearing on the same side of the thrust plate and the head cone, the air inlet of the second air supply hole is connected to the air source, and the air outlet of the second air supply hole faces the thrust plate; The cross-sectional area of ​​the second air supply hole is larger than the cross-sectional area of ​​the air inlet and outlet of the gas thrust bearing.

3. The gas turbine with a balanced axial force structure according to claim 2, characterized in that: In the gas thrust bearing provided with the second air supply holes, the plurality of air supply holes are arranged in a plurality of circles around the rotating shaft, and the number of the second air supply holes is a plurality and they are located between two adjacent circles of air supply holes; Or: In the gas thrust bearing provided with the second air supply holes, the second air supply holes are arranged around the rotating shaft, and each second air supply hole is surrounded by a plurality of air inlet holes.

4. The gas turbine with a balanced axial force structure according to claim 2, characterized in that: The second air supply hole is arranged obliquely, the air inlet of the second air supply hole is relatively far away from the rotating shaft, and the air outlet of the second air supply hole is relatively toward the rotating shaft.

5. The gas turbine with a balanced axial force structure according to claim 1, characterized in that: The gas source of the first gas supplement hole is a compressor; And / or, the air supply device connected to the air inlet of the gas thrust bearing is an external air pump.

6. The gas turbine with a balanced axial force structure according to claim 1, characterized in that: The turbine thrust component is provided with a second gas sealing hole, the gas outlet of the second gas sealing hole faces the turbine, and the turbine has a receiving surface corresponding to the second gas sealing hole; the cross-sectional area of ​​the second gas sealing hole is smaller than the cross-sectional area of ​​the third gas supplement hole; And / or, the turbine thrust component has a toothed portion on a side facing the turbine to form a tooth seal with the turbine.

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