Rotor system and gas turbine

Abstract

The present invention discloses a rotor system, including a rotating shaft, a compressor and a turbine which are sequentially mounted on the rotating shaft in the axial direction, and an inner air bearing located at one axial end of the rotating shaft, wherein the turbine has a hollow structure and includes a turbine inner cavity and a turbine air film hole which are connected to each other; the rotating shaft has a shaft connecting hole at a position corresponding to the turbine, and at least one axial end has a shaft inner bearing cavity, the shaft inner bearing cavity is connected to the shaft connecting hole through an inner shaft air path, and the shaft connecting hole is connected to the turbine inner cavity through a turbine connecting hole of the turbine; an air film gap of a gas bearing is formed between the part of the inner air bearing extending into the shaft inner bearing cavity and the circumferential inner wall of the shaft inner bearing cavity, and the inner air bearing has an air supply channel connected to the shaft inner bearing cavity. The rotor system disclosed by the present invention, when applied to a gas turbine, can enhance the cooling of the turbine, and further increase the temperature before the turbine, so as to improve the efficiency of the gas turbine. The present invention also discloses a gas turbine.

Description

Technical Field

[0001] The invention belongs to the field of thermal engines, and in particular relates to a rotor system and a gas turbine. Background Art

[0002] The gas turbine is mainly composed of three parts: compressor, combustion chamber and turbine, and is equipped with intake, exhaust, control, transmission and other auxiliary systems. It uses air as the medium and is a rotary power machine that converts the heat energy generated by fuel combustion into mechanical work for external output. Its working process is as follows: the compressor, which is driven by the turbine and rotates, continuously inhales air from the atmosphere and compresses and increases the pressure. The compressed air enters the combustion chamber, mixes with the injected fuel and burns, becomes high-temperature combustion gas, flows into the turbine to expand and do work, and the pressure of the combustion gas after doing work drops to atmospheric pressure and is finally discharged into the atmosphere. The high-temperature combustion gas formed after combustion and heating has greatly improved its work capacity, making the turbine's work output significantly greater than the compressor's work consumption, and there is more surplus work to output to drive the load.

[0003] Existing studies have shown that the thermal efficiency and power output of gas turbines increase with the increase of turbine inlet temperature. Generally, for every 40°C increase in turbine inlet temperature, the gas turbine output power can be increased by 10% and the thermal efficiency can be increased by 1.5% [1]. However, the increase in turbine inlet temperature is limited by the tolerance temperature of the turbine blade material directly exposed to high-temperature combustion gas, as well as the cooling effect of the turbine blade. A significant increase in turbine inlet temperature may lead to a decrease in the structural strength of the turbine blade, which in turn causes blade deformation or ablation failure. Therefore, turbine blades directly determine the performance level of gas turbines to a certain extent. How to increase the turbine inlet temperature while ensuring the long life and safe operation of the gas turbine is a key technical problem in the development of high-performance gas turbines.

[0004] Li Xiaotang, Hou Lingyun, Yang Min, et al. Modern gas turbine technology[M]. Beijing: Aviation Industry Press, 2006: 23-24. Summary of the invention

[0005] The object of the present invention is to provide a rotor system and a gas turbine to address the deficiencies in the prior art, which can enhance the cooling effect of the turbine and further increase the turbine inlet temperature to improve the efficiency of the gas turbine.

[0006] The present invention adopts the following technical solution:

[0007] In the first aspect, an embodiment of the present invention provides a rotor system, comprising a rotating shaft, a compressor and a turbine installed on the rotating shaft in sequence in the axial direction, and an inner air bearing located at one axial end of the rotating shaft, wherein the turbine has a hollow structure and comprises a turbine inner cavity and a turbine air film hole connected to each other; the rotating shaft has a shaft connecting hole at a position corresponding to the turbine, and has a shaft inner bearing cavity at at least one axial end, the shaft inner bearing cavity is connected to the shaft connecting hole through an inner shaft air path, and the shaft connecting hole is connected to the turbine inner cavity through the turbine connecting hole of the turbine; an air film gap of a gas bearing is formed between a part of the inner air bearing extending into the shaft inner bearing cavity and a circumferential inner wall of the shaft inner bearing cavity, and the inner air bearing has an air supply channel connected to the shaft inner bearing cavity.

[0008] Furthermore, the inner air bearing has a plurality of first air holes extending radially and arranged circumferentially, the air inlets of the first air holes are connected to the air source, and the air outlets of the first air holes face the circumferential inner wall of the inner bearing cavity of the shaft.

[0009] Furthermore, each first air hole is located in the axial direction between the outer opening of the bearing cavity in the shaft and the air outlet of the air supply channel.

[0010] Furthermore, the air supply channel has an expanded opening with an increased diameter corresponding to its air outlet, and the first air hole is opened corresponding to the expanded opening.

[0011] Further, the portion of the inner air bearing extending into the inner bearing cavity of the shaft includes an inner bearing ring arranged along the circumferential direction, and a portion of the first air hole is arranged in the inner bearing ring.

[0012] Furthermore, one end of the rotating shaft corresponding to the inner air bearing has a nose cone, and the inner air bearing has a nose cone air supply hole.

[0013] Furthermore, a second thrust bearing is provided on a side of the nose cone axially away from the inner air bearing.

[0014] Further, the gas pressure provided through the air supply passage is greater than the turbine inlet pressure of the turbine.

[0015] Furthermore, the air inlet of the air supply passage is connected to the exhaust end of the compressor.

[0016] Further, at least part of the blades in the turbine include a plurality of turbine film holes, and the turbine film holes are located at the leading edge, the trailing edge and / or the blade top of the turbine blade.

[0017] Furthermore, the turbine air film holes located at the leading edge of the blade are arranged in an array.

[0018] Furthermore, the turbine air film holes located at the blade top are reused as bearing spray holes at the turbine.

[0019] In a second aspect, an embodiment of the present invention provides a gas turbine, comprising a rotor system as described above, and a combustion chamber, wherein an inlet end of the combustion chamber is connected to an exhaust end of a compressor, and a guide vane assembly is provided at an outlet end of the combustion chamber, and the guide vane assembly is located in front of the turbine.

[0020] Furthermore, the turbine also includes a turbine thrust nozzle, and an air outlet of the turbine thrust nozzle faces the first support wall surface of the guide vane assembly.

[0021] Furthermore, the gas turbine also includes a second bearing seat, and the inner air bearing is installed on the second bearing seat through a damping assembly.

[0022] According to the rotor system of the embodiment of the present invention, when applied to a gas turbine, a turbine with a hollow structure is provided, and a cooling air film is formed on the outer wall of the turbine during the operation of the gas turbine to protect the turbine, thereby further increasing the temperature of the gas before the turbine to improve the efficiency of the gas turbine. In addition, by providing an inner shaft bearing cavity and an inner shaft connecting hole in the rotating shaft, and providing an inner air bearing with an air supply channel, pressurized air can be provided to the turbine while achieving the support of the rotating shaft, and the end of the inner shaft bearing cavity can be sealed by the air film of the air bearing, thereby ensuring the air supply stability of the turbine, so that a stable cooling air film is formed on the outer wall of the turbine to ensure the cooling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Other features, objects and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings, in which the same or similar reference numerals represent the same or similar features and the accompanying drawings are not drawn to scale.

[0024] Figure 1 is a schematic structural diagram of a rotor system according to an embodiment of the present invention;

[0025] Figure 2 for Figure 1 A partial enlarged schematic diagram of the middle turbine;

[0026] Figure 3 for Figure 1 An enlarged schematic diagram of the rotating shaft;

[0027] Figure 4 for Figure 1 A schematic structural diagram of an embodiment of a central air bearing;

[0028] Figure 5 for Figure 1 A schematic structural diagram of another embodiment of an inner air bearing;

[0029] Figure 6 for Figure 1 A schematic structural diagram of another embodiment of the inner air bearing;

[0030] Figure 7 is a schematic structural diagram of a rotor system according to another embodiment of the present invention;

[0031] Figure 8 is a schematic structural diagram of a rotor system according to yet another embodiment of the present invention;

[0032] Fig. 9 is a schematic structural diagram of a rotor system according to yet another embodiment of the present invention;

[0033] Fig.10 A schematic structural diagram of an embodiment of a turbine in a rotor system according to an embodiment of the present invention;

[0034] Fig.11 is a schematic structural diagram of another embodiment of a turbine in a rotor system according to an embodiment of the present invention;

[0035] Fig.12 for Fig.11 BB cross-section diagram;

[0036] Fig.13 is a schematic diagram of a flow field of a turbine according to an embodiment of the present invention from a first angle;

[0037] Fig.14 A second angle schematic diagram of a flow field of a turbine according to an embodiment of the present invention;

[0038] Fig.15 is a schematic diagram of a temperature field of a turbine according to an embodiment of the present invention;

[0039] Fig.16 is a schematic structural diagram of a gas turbine according to an embodiment of the present invention;

[0040] Fig.17 for Fig.16 A partial enlarged schematic diagram of the middle turbine;

[0041] Fig.18 for Fig.16 A partial enlarged schematic diagram of an embodiment of the inner air bearing;

[0042] Fig.19 for Fig.16 A partially enlarged schematic diagram of another embodiment of the inner air bearing. DETAILED DESCRIPTION

[0043] The features and exemplary embodiments of various aspects of the present invention will be described in detail below. In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only configured to explain the present invention and are not configured to limit the present invention. For those skilled in the art, the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention.

[0044] The efficiency of a gas turbine is positively correlated with the temperature before the turbine. However, when the temperature before the turbine is too high and exceeds the heat resistance limit of the turbine material, the turbine cannot continue to work normally. Therefore, people are committed to developing materials with higher heat resistance, but the development progress is relatively slow, and the price of new materials is high, resulting in a significant increase in the cost of gas turbines.

[0045] The inventors have found that the turbine can be protected by air film cooling or liquid film cooling to improve the material stability of the turbine at a higher turbine front temperature. However, using only the centrifugal force of the turbine to increase the cooling air pressure is often lower than or slightly higher than the static pressure before the turbine, so an effective cooling air film will not be formed. Liquid film cooling has high requirements for the coolant, such as deionized water, and requires continuous consumption of coolant, which is difficult to reuse, resulting in increased costs.

[0046] Therefore, there is an urgent need for a rotor system that, when applied to a gas turbine, can improve the cooling effect of the turbine, thereby achieving efficiency improvement by increasing the temperature before the turbine, while ensuring that the cooling is continuous and easy to implement, and controlling the manufacturing and modification costs.

[0047] To achieve the above purpose, Figure 1 As shown, Figure 1 The present invention provides a rotor system, comprising a rotating shaft 100, a compressor 200 and a turbine 300 sequentially mounted on the rotating shaft 100 in the axial direction, and an inner air bearing 510 located at one axial end of the rotating shaft 100.

[0048] The compressor 200 may be an axial flow compressor, a centrifugal compressor or a diagonal flow compressor. In some embodiments, the compressor 200 may include a compressor impeller and a diffuser. The air intake end of the compressor 200 is connected to the external environment for air intake, and the inhaled gas (e.g., air) is compressed by the compressor 200 and then enters the combustion chamber through the exhaust end of the compressor 200.

[0049] The turbine 300 may be an axial flow turbine. In other embodiments, the turbine 300 may also be a centrifugal turbine. The material of the turbine 300 may be a high temperature resistant material, such as nickel or a nickel alloy. The turbine 300 is generally connected to the exhaust end of the combustion chamber 400 to receive the high temperature gas from the combustion chamber 400 and use the high temperature gas to perform work.

[0050] Specifically, Figure 2 As shown, Figure 2 for Figure 1 A partially enlarged schematic diagram of the turbine, the turbine 300 has a hollow structure and includes a turbine inner cavity 320 and a turbine air film hole 302 connected to each other. Figure 1 and Figure 2 The turbine 300 is exemplarily shown as a hollow turbine, specifically including a turbine housing 310, a turbine inner cavity 320 formed by surrounding the turbine housing 310, and a turbine air film hole 302 opened in the turbine housing 310 and connected to the turbine inner cavity 320. The hollow turbine 300 can be formed by two or more pieces of shell parts fixedly connected (for example, welded). In other embodiments, the turbine inner cavity 320 can also be a connecting channel to supply air to the turbine air film hole 302. In other embodiments, a baffle, a baffle column or a labyrinth structure can be provided in the turbine inner cavity 320 to increase the cooling effect inside the turbine, so as to further improve the overall cooling effect of the turbine 300.

[0051] The material of the rotating shaft 100 can be steel, or other suitable metals, alloys or composite materials. The rotating shaft 100 is supported on the housing or bearing seat of the gas turbine through a bearing. The bearing is preferably an air bearing, or other non-contact bearings such as a magnetic bearing or an air-magnetic hybrid bearing.

[0052] Specifically, Figure 3 As shown, Figure 3 for Figure 1 The enlarged schematic diagram of the rotating shaft shows that the rotating shaft 100 has a shaft connecting hole 150 at the position corresponding to the turbine 300, so as to provide cooling air to the turbine 300 through the shaft connecting hole 150 inside the rotating shaft 100. In addition, at least one axial end of the rotating shaft 100 has an inner shaft bearing cavity 120. Figure 3 It is shown that the inner shaft bearing cavity 120 is located at one end corresponding to the compressor 200. In other embodiments, the inner shaft bearing cavity 120 can also be located at the other end opposite to the compressor 200. The inner shaft bearing cavity 120 is connected to the shaft connecting hole 150 through the inner shaft gas path 140, and the shaft connecting hole 150 is connected to the turbine inner cavity 320 through the turbine connecting hole 301 of the turbine 300. In this way, the cooling air from the outside first enters the inner shaft bearing cavity 120, then enters the turbine inner cavity 320 through the inner shaft gas path 140 and the shaft connecting hole 150, and then is ejected through the turbine air film hole 302 to form a cooling air film on the outer wall of the turbine 300.

[0053] Relative to the rotating shaft 100, the inner air bearing 510 is a stator component, and the inner air bearing 510 can be installed in the housing or bearing seat of the gas turbine, for example. The inner air bearing 510 at least partially extends into the inner bearing cavity 120 of the shaft, and the portion of the inner air bearing 510 extending into the inner bearing cavity 120 of the shaft and the circumferential inner wall of the inner bearing cavity 120 of the shaft form an air film gap of the gas bearing. The inner air bearing 510 supports the rotating shaft 100 for rotation, and the inner air bearing 510 is located at one end of the rotating shaft 100 to at least partially close the opening of the inner bearing cavity 120 of the shaft, and the remaining gap is sealed by the air film formed during the operation of the inner air bearing 510. The inner air bearing 510 has an air supply channel 511 connected to the inner bearing cavity 120 of the shaft to provide turbine cooling air to the inner bearing cavity 120 of the shaft.

[0054] According to the rotor system of the embodiment of the present invention, when it is applied to a gas turbine, by providing a turbine 300 with a hollow structure, when the rotor system is applied to the gas turbine, a cooling air film is formed on the outer wall of the turbine 300 during the operation of the gas turbine to protect the turbine 300, thereby further increasing the temperature of the gas before the turbine to improve the efficiency of the gas turbine. In addition, by providing an inner shaft bearing cavity 120 and an inner shaft connecting hole 301 in the rotating shaft 100, and providing an inner air bearing 510 with an air supply channel 511, it is possible to supply pressurized air to the turbine 300 while supporting the rotating shaft 100, and to achieve air sealing at the end of the inner shaft bearing cavity 120 through the air film of the inner air bearing 510, thereby ensuring the air supply stability of the turbine 300, so that a stable cooling air film is formed on the outer wall of the turbine 300 to ensure the cooling effect.

[0055] Furthermore, the gas pressure provided by the air supply channel 511 is greater than the turbine pre-pressure of the turbine 300, so that the cooling gas can withstand the turbine pre-pressure and be ejected through the turbine film hole 302 to form a cooling air film.

[0056] Specifically, the air inlet of the air supply passage 511 is connected to the exhaust end of the compressor 200 , and the pressure at the exhaust end of the compressor 200 is greater than the pre-turbine pressure of the turbine 300 .

[0057] Furthermore, if Figure 4 As shown, Figure 4 for Figure 1 A schematic diagram of the structure of an embodiment of the inner air bearing, the inner air bearing 510 has a plurality of first air holes 512 extending radially and arranged circumferentially, the air inlet of the first air hole 512 is connected to the air source, and the air outlet of the first air hole 512 faces the circumferential inner wall of the inner shaft bearing cavity 120. The air source can be an external air source, such as an air pump. The air source can also be a compressor 200, for example, the air inlet of the first air hole 512 is connected to the exhaust end of the compressor 200. Figure 4It is shown that the air inlet of the first air hole 512 is connected to the air supply channel 511, and the air supply channel 511 is connected to the air source. In other optional embodiments, the air inlet of the first air hole 512 can also be connected to the air source through other channels.

[0058] Specifically, the axial position of each first air hole 512 is located between the external opening of the in-shaft bearing cavity 120 and the air outlet of the air supply channel 511 , so that the air outlet of the air supply channel 511 is located inside the in-shaft bearing cavity 120 and can achieve air sealing through each first air hole 512 .

[0059] During the operation of the gas turbine using this rotor system, the first air hole 512 sprays air toward the circumferential wall of the shaft bearing cavity 120 to form an air film. The air film supports the rotation of the rotating shaft 100 and forms an air seal between the rotating shaft 100 and the inner air bearing 510, so that the turbine cooling air provided by the air supply channel 511 of the inner air bearing 510 to the shaft bearing cavity 120 is leaked as little as possible to ensure the cooling effect.

[0060] In some optional embodiments, the first air hole 512 is a stepped hole, and the large end of the stepped hole faces the inner air bearing 510. The stepped hole can further increase the velocity of the incoming air flow to further enhance the strength of the air film.

[0061] In some optional embodiments, the first air holes 512 are arranged in more than two circles along the axial direction to increase the air output, ensure the strength of the air film, and increase the stability of the inner air bearing 510 .

[0062] In some optional embodiments, such as Figure 5 As shown, Figure 5 for Figure 1 A schematic diagram of the structure of another embodiment of the inner air bearing, the air supply channel 511 has a flared opening 513 with an increased diameter corresponding to its air outlet, and the first air hole 512 is opened corresponding to the flared opening 513. The flared opening 513 having a larger diameter than the original air supply channel 511 is provided to facilitate the machining tool (such as a hook cutter) to penetrate into the flared opening 513 to machine the large end of the first air hole 512, and then the small end of the first air hole 512 can be machined by laser drilling, for example.

[0063] In some other optional embodiments, such as Figure 6 As shown, Figure 6 for Figure 1A schematic diagram of the structure of another embodiment of the inner air bearing, the portion of the inner air bearing 510 extending into the inner bearing cavity 120 of the shaft includes an inner bearing ring 512 arranged along the circumferential direction. The inner bearing ring 512 is in the shape of an annular tube, and can be sleeved on the body of the inner air bearing 510 with an interference fit. A portion of the first air hole 512 is arranged on the inner bearing ring 512, that is, a portion of the first air hole 512 is opened along the circumference of the inner bearing ring 512, and another portion of the first air hole 512 is arranged on the body of the inner air bearing 510, and the two portions are connected and together constitute the first air hole 512. Figure 6 In the example shown, when the first air hole 512 is a stepped hole, the small end of the first air hole 512 is arranged on the inner bearing ring 512. The arrangement of this embodiment can facilitate the processing of the first air hole 512, especially the first air hole 512 processed as a stepped hole, and the processing method can be, for example, using a hook cutter to process the large end of the inner bearing ring 512, and then using a laser to process the small end.

[0064] Furthermore, if Figure 7 As shown, Figure 7 1 is a schematic diagram of the structure of a rotor system according to another embodiment of the present invention, wherein the rotor system further comprises a first radial bearing 520 and a first thrust bearing 530 disposed between the compressor 200 and the turbine 300. The first radial bearing 520 is an external air bearing sleeved on the outer peripheral surface of the rotating shaft 100. The air film medium of the air bearing referred to herein may be a single component gas, ambient air or other mixed component gas. The number of the first radial bearings 520 may be more than two, and the more than two first radial bearings 520 may be disposed on both axial sides of the first thrust bearing 530. A thrust plate 130 is disposed on the rotating shaft 100, and the first thrust bearings 530 are disposed on both axial sides of the thrust plate 130.

[0065] In some optional embodiments, such as Figure 8 As shown, Figure 8 This is a structural schematic diagram of a rotor system according to another embodiment of the present invention, in which a rotating shaft 100 has a nose cone 160 at one end corresponding to the inner air bearing 510. The nose cone 160 can be integrally formed on the rotating shaft 100, or can be fixedly mounted on the rotating shaft 100 by means of welding or a connecting piece. The end of the nose cone 160 facing the inner air bearing 510 in the axial direction has a thrust surface. The inner air bearing 510 has a nose cone air supply hole 515, and the air inlet end of the nose cone air supply hole 515 can be connected to the air supply channel 511, and the air outlet of the nose cone air supply hole 515 faces the thrust surface of the nose cone 160. The pressurized gas ejected from the nose cone air supply hole 515 can give the nose cone 160 an axial thrust, which is beneficial to the axial force balance of the rotor system. In other embodiments, the air inlet end of the nose cone air supply hole 515 can also be connected to the air source through other channels.

[0066] Furthermore, if Fig. 9As shown, Fig. 9 Schematic diagram of the structure of a rotor system according to another embodiment of the present invention, a second thrust bearing 540 is provided on the side of the nose cone 160 axially away from the inner air bearing 510. The second thrust bearing 540 can be set vertically or inclined according to the surface form of the nose cone 160. The second thrust bearing 540 can further facilitate the force balance in the axial direction of the rotor system. In this embodiment, when the nose cone 160 and the second thrust bearing 540 can meet the axial thrust requirements, the thrust plate 130 and the first thrust bearing 530 can be removed to shorten the length of the rotating shaft 100, reduce the weight of the rotating shaft 100, and help improve the rotation performance of the rotor system.

[0067] Furthermore, if Fig.10 As shown, Fig.10 300 is a schematic diagram of the structure of an embodiment of a turbine in a rotor system according to an embodiment of the present invention, wherein at least some blades in the turbine 300 include a plurality of turbine film holes 302. The turbine film holes 302 are located at the leading edge and blade tip of the turbine 300. The plurality of turbine film holes 302 located at the leading edge of the blade can be arranged along the radial direction of the turbine 300. The turbine film holes 302 are located at different positions to meet the cooling requirements of each position and to finely control the formation of the cooling film.

[0068] Specifically, Fig.11 and Fig.12 As shown, Fig.11 is a schematic structural diagram of another embodiment of a turbine in a rotor system according to an embodiment of the present invention, Fig.12 for Fig.11 In the BB cross-sectional view, the turbine film holes 302 located at the leading edge of the blade are arranged in an array to meet the cooling needs of different areas and directions and facilitate airflow guidance.

[0069] Further, such as Fig.11 As shown, the turbine film hole 302 located at the blade tip can be reused as a bearing spray hole at the turbine. On the one hand, the turbine film hole 302 located at the blade tip is used for cooling at the blade tip, and on the other hand, radial gas thrust can be formed between the blade tip with the turbine film hole 302 and the external casing. The pressurized gas ejected from the turbine film hole 302 at the blade tip can radially support the turbine 300 to a certain extent, which is beneficial to improving the rotation stability of the rotor system.

[0070] Further, such as Fig.11 As shown, the turbine air film hole 302 may also be located at the trailing edge of the blade of the turbine 300, and the air outlet from the trailing edge is beneficial to the airflow guidance.

[0071] Further Fig.13 and Fig.14 , Fig.13 is a first angle schematic diagram of a flow field of a turbine according to an embodiment of the present invention, Fig.14 This is a second angle schematic diagram of the flow field of the turbine according to an embodiment of the present invention, which shows a schematic diagram of the jet flow field of the turbine film hole 302 with turbine front pressure. The jet can form a cooling air film on the blade surface of the turbine 300, and the cooling air flows along the blade surface to the trailing edge of the blade.

[0072] Further Fig.15 As shown, Fig.15 It is a schematic diagram of the temperature field of the turbine according to an embodiment of the present invention. The scale on the left is the temperature scale. The lighter the color, the higher the temperature. It can be seen from the figure that the rotor system provided by the embodiment of the present invention can effectively reduce the temperature of the turbine 300 blades, thereby ensuring the material performance at a higher turbine inlet temperature, improving the efficiency while meeting the premise of long-life safe operation of the gas turbine.

[0073] like Fig.16 As shown, Fig.16 1 is a schematic diagram of the structure of a gas turbine according to an embodiment of the present invention. The present invention also provides a gas turbine, comprising a rotor system according to any of the aforementioned embodiments, and a combustion chamber 400. The combustion chamber 400 may be an annular combustion chamber, a single-tube combustion chamber, an annular tube combustion chamber, etc. The combustion chamber 400 may be arranged around the rotating shaft 100, and the inlet end of the combustion chamber 400 is connected to the exhaust end of the compressor 200, and the outlet end of the combustion chamber 400 is provided with a guide vane assembly 700, and the guide vane assembly 700 is located in front of the turbine 300.

[0074] According to the gas turbine of the embodiment of the present invention, by providing a turbine 300 with a hollow structure, a cooling air film is formed on the outer wall of the turbine 300 during the operation of the gas turbine to protect the turbine 300, thereby further increasing the temperature of the gas before the turbine to improve the efficiency of the gas turbine. In addition, by providing an inner shaft bearing cavity 120 and an axis connecting hole 301 in the rotating shaft 100, and providing an inner air bearing 510 with an air supply channel 511, it is possible to supply pressurized air to the turbine 300 while supporting the rotating shaft 100, and to achieve air sealing at the end of the inner shaft bearing cavity 120 through the air film of the inner air bearing 510, thereby ensuring the air supply stability of the turbine 300, so that a stable cooling air film is formed on the outer wall of the turbine 300 to ensure the cooling effect.

[0075] Furthermore, the gas turbine further includes a first bearing seat 600 , in which the first radial bearing 520 and the first thrust bearing 530 can be installed.

[0076] Further, such as Fig.17 As shown, Fig.17 for Fig.16A partial enlarged schematic diagram of the middle turbine, the gas turbine also includes a guide vane assembly 700, the guide vane assembly 700 includes a first support 710, a second support 730 and a blade group 720 with an axial air passage located between the two supports. The turbine 300 also includes a turbine thrust nozzle 305, the outlet of the turbine thrust nozzle 305 faces the wall of the first support 710 of the guide vane assembly 700, and the pressure gas ejected from the turbine thrust nozzle 305 can form an axial thrust, which is beneficial to the axial balance of the rotor system of the gas turbine. Further, sealing holes 306 can be provided on both sides of the turbine thrust nozzle 305, the diameter of the sealing hole 306 is smaller than the diameter of the turbine thrust nozzle 305, and the pressure gas ejected from the sealing hole 306 can form an air curtain seal to seal the jet of the turbine thrust nozzle 305 as much as possible to increase the thrust.

[0077] Further, such as Fig.18 and Fig.19 As shown, Fig.18 for Fig.16 A partial enlarged schematic diagram of an embodiment of the inner air bearing, Fig.19 for Fig.16 A partial enlarged schematic diagram of another embodiment of the inner air bearing, the gas turbine also includes a second bearing seat 800, and the inner air bearing 510 is installed on the second bearing seat 800 through a damping assembly 830, wherein the damping assembly 830 can be an elastic member (such as a sealing ring) reused as a seal, and the damping assembly 830 can provide an air seal while compensating for the directional jump of the inner air bearing 510. Fig.18 and Fig.19 Different configurations of the second bearing seat 800 are shown. The second bearing seat 800 is provided with a channel 810 to supply air to the air supply channel 511 .

[0078] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0079] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0080] In the description of the present invention, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0081] According to the embodiments of the present invention as described above, these embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made based on the above description. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can make good use of the present invention and the modified use based on the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A rotor system, characterized in that: It includes a rotating shaft, a compressor and a turbine which are sequentially mounted on the rotating shaft in the axial direction, and an inner air bearing located at one axial end of the rotating shaft, wherein: The turbine has a hollow structure and includes a turbine inner cavity and a turbine air film hole connected to each other; The rotating shaft has a shaft connecting hole at a position corresponding to the turbine, and has a shaft inner bearing cavity at at least one axial end, the shaft inner bearing cavity is connected to the shaft connecting hole through a shaft inner gas path, and the shaft connecting hole is connected to the turbine inner cavity through a turbine connecting hole of the turbine; An air film gap of a gas bearing is formed between a portion of the inner air bearing extending into the inner bearing cavity of the shaft and a circumferential inner wall of the inner bearing cavity of the shaft, and the inner air bearing has an air supply channel communicating with the inner bearing cavity of the shaft; The gas pressure provided by the air supply passage is greater than the turbine pre-turbine pressure of the turbine, and / or the air inlet of the air supply passage is connected to the exhaust end of the compressor; The inner air bearing has a plurality of first air holes extending radially and arranged circumferentially, wherein the air inlet of the first air holes is connected to the air source, and the air outlet of the first air holes faces the circumferential inner wall of the inner bearing cavity of the shaft; the axial position of each first air hole is located between the external opening of the inner bearing cavity of the shaft and the air outlet of the air supply channel.

2. The rotor system according to claim 1, characterized in that The air supply channel has an expanded opening with an increased diameter corresponding to its air outlet, and the first air hole is opened corresponding to the expanded opening; Alternatively, the portion of the inner air bearing extending into the inner bearing cavity of the shaft includes an inner bearing ring arranged along the circumferential direction, and a portion of the first air hole is arranged in the inner bearing ring.

3. The rotor system according to claim 2, characterized in that One end of the rotating shaft corresponding to the inner air bearing is provided with a nose cone, and the inner air bearing is provided with a nose cone air supply hole.

4. The rotor system according to claim 3, characterized in that A second thrust bearing is arranged on a side of the nose cone axially away from the inner air bearing.

5. The rotor system according to claim 1, characterized in that At least part of the blades in the turbine include a plurality of the turbine air film holes, and the turbine air film holes are located at the leading edge, the trailing edge and / or the blade top of the turbine blade; The turbine air film holes located at the leading edge of the blade are arranged in an array; The turbine air film holes located at the blade tops are reused as bearing spray holes at the turbine.

6. A gas turbine, characterized in that: It comprises a rotor system as described in any one of claims 1 to 5, and a combustion chamber, wherein the inlet end of the combustion chamber is connected to the exhaust end of the compressor, and the outlet end of the combustion chamber is provided with a guide vane assembly, and the guide vane assembly is located in front of the turbine.

7. The gas turbine according to claim 6, characterized in that The turbine further comprises a turbine thrust spray hole, wherein an air outlet of the turbine thrust spray hole faces a wall surface of the first support of the guide vane assembly.

8. The gas turbine according to claim 7, characterized in that The gas turbine also includes a second bearing seat, and the inner air bearing is mounted on the second bearing seat through a damping assembly.

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