Turbine blade cooling system of hydrogen gas turbine and hydrogen gas turbine

Abstract

The invention belongs to a cooling system, and provides a hydrogen gas turbine turbine blade cooling system and a hydrogen gas turbine aiming at the technical problem that a traditional air cooling means at present cannot meet the requirement of turbine blades for higher cooling efficiency. The first pressure fuel pump, the second pressure fuel pump, the heat exchanger and the heat regenerator are sequentially connected to enable hydrogen to flow through, and an inlet of the first pressure fuel pump is connected with a hydrogen source. The first pressure fuel pump and the second pressure fuel pump are used for sequentially pressurizing hydrogen. A heat exchange medium of the heat exchanger is lubricating oil of the hydrogen gas turbine. A heat source of the heat regenerator is heat in high-temperature fuel gas exhausted by a turbine of the hydrogen gas turbine, the heat regenerator is provided with two outlets, the first outlet is connected with an inlet of the inner cooling channel, and the second outlet is connected with the hydrogen turbocharging device. An outlet of the inner cooling channel located in the middle chord area of the turbine blade to be cooled is connected with an inlet of the hydrogen turbocharging device, and an outlet of the hydrogen turbocharging device is connected with a combustion chamber of the hydrogen gas turbine.

Description

Technical Field

[0001] The present application relates to a cooling system, and specifically to a hydrogen gas engine turbine blade cooling system and a hydrogen gas turbine. Background Art

[0002] Under the general trend of global energy transformation and addressing climate change, the strategic position of hydrogen energy in the energy structure is becoming increasingly prominent. Among them, hydrogen gas turbines (referred to as hydrogen gas turbines) have become one of the core research objects in the field of hydrogen power equipment due to their high efficiency and zero carbon emissions.

[0003] High-temperature turbine blades are the core and key components of hydrogen-fired engines. By increasing the inlet temperature of the turbine rotor, the thermal efficiency and output power of hydrogen-fired engines can be effectively improved. Turbine blades are subjected to high temperatures, high stresses, and high corrosion conditions above the melting point of metals for a long time. Therefore, it is urgent to develop advanced cooling technologies to ensure the safe and reliable operation of turbine blades. However, the current traditional air cooling method can no longer meet the demand for higher cooling efficiency of turbine blades due to insufficient cooling capacity. Summary of the invention

[0004] The present application aims to solve the technical problem that the current traditional air cooling method cannot meet the demand for higher cooling efficiency of turbine blades, and provides a hydrogen gas turbine turbine blade cooling system and a hydrogen gas turbine.

[0005] In order to achieve the above objectives, this application adopts the following technical solutions: In a first aspect, the present application provides a hydrogen combustion engine turbine blade cooling system, comprising a hydrogen turbocharger, and a first pressure fuel pump, a second pressure fuel pump, a heat exchanger, and a regenerator connected in sequence to allow hydrogen to flow; The inlet of the first pressure fuel pump is connected to a hydrogen source; the first pressure fuel pump and the second pressure fuel pump are used to pressurize the hydrogen in sequence; The heat exchange medium of the heat exchanger is the lubricating oil of the hydrogen combustion engine, which is used to preheat the hydrogen; The heat source of the regenerator is the heat in the high-temperature combustion gas discharged from the hydrogen engine turbine. The regenerator is provided with two outlets, the first outlet is connected to the inlet of the inner cooling channel located in the mid-chord area of ​​the turbine blade to be cooled, and is used for secondary preheating of the hydrogen, and the second outlet is connected to the hydrogen turbocharger; The outlet of the inner cooling channel located in the mid-chord area of ​​the turbine blade to be cooled is connected to the inlet of the hydrogen turbocharger, and the outlet of the hydrogen turbocharger is connected to the combustion chamber of the hydrogen engine. The hydrogen turbocharger is used to pressurize the hydrogen before entering the combustion chamber.

[0006] Furthermore, ribs are provided on two opposite inner walls of the inner cooling channel.

[0007] Furthermore, the ribs are V-shaped.

[0008] Furthermore, each of the fins comprises a plurality of sub-fins, and gaps are left between adjacent sub-fins; the gaps between two adjacent fins are staggered.

[0009] Furthermore, the ratio of the distance between two adjacent fins to the fin height is in the range of 3-6.

[0010] Furthermore, the dimensions of the fins include: According to the heat exchange requirements, the ratio of the fin height to the inner cooling channel height should be greater than 0.25; Alternatively, in combination with heat exchange requirements and hydrogen flow requirements, the ratio of the fin height to the inner cooling channel height is made less than 0.05.

[0011] Furthermore, the ratio of the height to the width of the fin is 1.

[0012] Furthermore, the ribs are arranged to be inclined relative to the surface on which the ribs are installed, and the inclination angle of the ribs is 30° to 90°.

[0013] In a second aspect, the present application proposes a hydrogen gas turbine, comprising a combustion chamber and a turbine; and also comprising the above-mentioned hydrogen gas engine turbine blade cooling system.

[0014] Furthermore, air cooling channels are provided on the leading edges and trailing edges of the turbine blades in the turbine.

[0015] Compared with the prior art, this application has the following beneficial effects: The present application proposes a hydrogen engine turbine blade cooling system, including a hydrogen turbocharger, and a first pressure fuel pump, a second pressure fuel pump, a heat exchanger and a regenerator connected in sequence to allow hydrogen to flow. Hydrogen medium is directly used as the coolant of the turbine blades, and the hydrogen fuel is first preliminarily heated by the heat exchanger, then enters the regenerator to reach a suitable temperature, and then is efficiently convectively cooled through the internal cooling channel of the turbine blades, and returns to the turbocharger cycle after absorbing the heat generated by the turbine blades, and finally provides high-efficiency fuel for the hydrogen engine. This process avoids the energy loss and air consumption caused by the additional heat exchange link of the cold air cooling heat exchanger in the existing hydrogen turbine engine cycle, and can further improve the overall efficiency of the hydrogen engine. In addition, the present application saves the air extracted from the compressor for cooling the turbine blades, which can improve the overall efficiency of the hydrogen engine. Preheating the hydrogen through the turbine blades can also further improve the overall efficiency of the hydrogen engine and significantly improve the cooling effect of the turbine blades.

[0016] The present application also proposes a hydrogen gas turbine having all the advantages of the above-mentioned hydrogen gas engine turbine blade cooling system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a schematic diagram of the hydrogen efficient cooling system for hydrogen combustion engine turbine blades in the present invention; Figure 2 This is a schematic diagram of the hydrogen / air dual-medium cooling structure of the turbine blades in the present invention; Figure 3 A flow chart of a design method for a cooling structure of a hydrogen-cooled ribbed channel for a turbine blade in the present invention; Figure 4 This is a schematic diagram of the structure of the hydrogen cooling ribbed channel of the turbine blade in the present invention; Figure 5 A diagram showing various fin forms in the hydrogen cooling ribbed channel of the turbine blade in the present invention; Figure 6 A diagram showing various fin arrangements in the hydrogen cooling ribbed channel of the turbine blade of the present invention; Figure 7 Scale diagram of various fins in the hydrogen cooling ribbed channel of the turbine blade in the present invention; Figure 8 It is a schematic diagram of the numerical calculation model of the hydrogen cooling ribbed channel of the turbine blade in the present invention; Fig. 9 Schematic diagram of the grid model of the hydrogen cooling ribbed channel of the turbine blade in the present invention; wherein (a) is the solid domain and (b) is the fluid domain; Fig.10 Schematic diagram for comparing numerical calculation results of hydrogen cooling ribbed channels of turbine blades in the present invention; wherein (a) is the result of air cooling, and (b) is the result of hydrogen cooling.

[0019] Among them, 1-hydrogen tank, 2-first pressure fuel pump, 3-second pressure fuel pump, 4-heat exchanger, 5-regenerator, 6-hydrogen turbocharger 6, 7-turbine, 8-combustion chamber, 9-blade trailing edge, 10-blade leading edge, 11-internal cooling channel, 12-fins, 13-air film holes, 14-cooling holes, 15-straightening section, 16-ribbed channel, 17-heating wall. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0021] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0023] In the description of the embodiments of the present application, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, or the orientation or position relationship in which the invented product is usually placed when used. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply 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 application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0024] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0025] In the description of the embodiments of the present application, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0026] The high efficiency of hydrogen gas turbines depends largely on the performance of high-temperature turbine blades, which are core components. High-temperature turbine blades operate in extreme working environments and must not only withstand temperatures far exceeding the melting point of metals, but also cope with huge stresses and challenges of corrosive media. Therefore, how to ensure the stable operation of turbine blades under such extreme conditions has become the key to improving the overall performance of hydrogen engines. Although traditional air cooling technology can alleviate the thermal load of blades to a certain extent, with the continuous improvement of hydrogen engine performance requirements, especially the continuous increase in turbine rotor inlet temperature to improve thermal efficiency and output power, the limitations of air cooling are becoming increasingly apparent. Its cooling capacity is insufficient and it is difficult to meet the urgent needs of modern hydrogen engines for efficient cooling.

[0027] In this context, it is particularly urgent to explore new and efficient cooling media. Hydrogen, as a medium with unique physical properties, has a high thermal conductivity, which means it can transfer heat faster, a high specific heat capacity, which allows it to absorb more heat without significant temperature rise, a high thermal diffusion coefficient, which helps to distribute heat more evenly inside the blade, and a low density, which reduces the mechanical burden of the cooling system on the blade. These characteristics make hydrogen an ideal choice to replace traditional air cooling media, and it is expected to play an important role in improving the cooling efficiency of turbine blades.

[0028] Compared with air, hydrogen has the characteristics of high thermal conductivity, high specific heat capacity, high thermal diffusion coefficient and low density. Therefore, when considering new cooling media, hydrogen becomes a very promising choice. However, the cooling structure and design method of hydrogen at the scale and working conditions of turbine blades need to be further studied and explored. It is necessary to conduct in-depth research on the flow characteristics, heat transfer mechanism and compatibility with other materials of hydrogen at the blade scale and actual working conditions. At the same time, it is also necessary to design targeted cooling structures to ensure that hydrogen can efficiently take away the heat generated by the blades without affecting the mechanical properties and stability of the blades.

[0029] Based on the above situation, the present application proposes a hydrogen gas engine turbine blade cooling system and a hydrogen gas turbine. The present application is described in detail below in conjunction with embodiments and drawings.

[0030] like Figure 1 As shown, a hydrogen combustion engine turbine blade cooling system is characterized by comprising a hydrogen turbocharger 6, and a first pressure fuel pump 2, a second pressure fuel pump 3, a heat exchanger 4 and a regenerator 5 which are sequentially connected to allow hydrogen to flow through; The inlet of the first pressure fuel pump 2 is connected to a hydrogen source; the first pressure fuel pump 2 and the second pressure fuel pump 3 are used to pressurize the hydrogen in sequence. In practical applications, hydrogen can be stored in a hydrogen tank 1, which stores high-pressure hydrogen for cooling and combustion as a hydrogen source. The first pressure fuel pump 2 transfers hydrogen from a storage state to the system to provide power for subsequent processes. The second pressure fuel pump 3 can further increase the pressure of hydrogen to ensure that it can be effectively transported to various parts of the hydrogen engine that require high pressure.

[0031] The heat exchange medium of the heat exchanger 4 is the lubricating oil of the hydrogen combustion engine, which is used to preheat the hydrogen. At the same time, the hydrogen is also used to cool the lubricating oil to improve efficiency.

[0032] The heat source of the regenerator 5 is the heat in the high-temperature combustion gas discharged from the hydrogen combustion engine turbine 7. The regenerator 5 is provided with two hydrogen outlets, the first outlet is connected to the inlet of the inner cooling channel 11 of the mid-chord area of ​​the turbine blade to be cooled, and is used for secondary preheating of the hydrogen, and the second outlet is directly connected to the hydrogen turbocharger 6. The regenerator 5 recovers the heat in the high-temperature combustion gas discharged from the turbine 7 to preheat the hydrogen before entering the turbine blade cooling channel, thereby improving efficiency.

[0033] The outlet of the inner cooling channel 11 located in the mid-chord area of ​​the turbine blade to be cooled is connected to the inlet of the hydrogen turbocharger 6, and the outlet of the hydrogen turbocharger 6 is connected to the combustion chamber 8 of the hydrogen combustion engine. The hydrogen turbocharger 6 is used to pressurize the hydrogen before entering the combustion chamber 8. The turbine 7 converts the kinetic energy of the high-temperature combustion gas after the hydrogen combustion into mechanical energy and outputs power to the outside. The hydrogen turbocharger 6 uses the exhaust gas energy to compress the intake air, increase the hydrogen density, and thus improve the combustion efficiency. The combustion chamber 8 is where the hydrogen is mixed with the air and ignited, generating high-temperature and high-pressure gas that drives the turbine blades.

[0034] This application solves the technical problems of low cooling efficiency of hydrogen engine turbine blades and difficulty in improving the efficiency of the whole machine in the prior art. The use of hydrogen for turbine blade cooling has very important scientific and practical significance for ensuring the safe and reliable operation and efficiency improvement of hydrogen engines, and will promote the innovation and breakthrough of independent technologies in the field of hydrogen energy high-end power equipment, promote the upgrading of clean energy power systems, and enhance the position of hydrogen energy technology in the competition, which is of great significance to helping achieve the dual carbon goals.

[0035] The principle of efficient cooling of hydrogen in the inner cooling channel 11 of the mid-chord area of ​​the turbine blade of the hydrogen combustion engine in this embodiment is as follows: the hydrogen fuel is first preliminarily heated by the lubricating oil / hydrogen heat exchanger 4, then enters the regenerator 5 to reach a suitable temperature, and then is efficiently convectively cooled by the inner cooling channel 11 of the mid-chord area of ​​the turbine blade, and returns to the turbine 7 for supercharging circulation after absorbing the heat generated by the blade, and finally provides high-efficiency fuel for the hydrogen combustion engine. This process avoids the energy loss and air consumption caused by the additional heat exchange link of the cold air cooling heat exchanger 4, and can further improve the overall efficiency of the hydrogen combustion engine.

[0036] In some embodiments of the present application, fins 12 are provided on two opposite inner walls of the inner cooling channel 11 to further improve the cooling effect. The principle of efficient cooling of the fins 12 in the inner cooling channel 11 is as follows: fin 12 turbulence cooling is one of the most widely used cooling methods in the chord region of a gas turbine blade. It refers to the arrangement of periodically distributed fin 12 turbulents on the pressure and suction surfaces of the turbine blades. The turbulence effect of the fins 12 increases the heat exchange between the cold fluid and the heated wall surface, thereby enhancing the heat transfer performance of the inner cooling channel 11. Furthermore, by reasonably adjusting the form, arrangement and scale of the fins 12, the heat transfer performance and cooling effect of the inner cooling channel 11 in the chord region of a hydrogen engine turbine blade can be further improved.

[0037] As an optimized structural design of the fins 12, the aspect ratio of the hydrogen cooling channel can be in the range of 0.25-4.

[0038] In practical applications, the form, arrangement and scale of the fins 12 can be designed according to actual conditions. Specifically, the whole design process of the hydrogen-cooled ribbed channel cooling structure, including experimental design, geometric modeling, meshing, numerical calculation, post-processing, and data analysis, can be adopted, which can provide a reference for designers of efficient cooling structures for hydrogen-fired engine turbine blades. The introduction of the fins 12 not only increases the heat exchange area, but also promotes the turbulent flow of the cooling medium (hydrogen) in the channel, thereby enhancing the ability of heat conduction and convection heat transfer.

[0039] The following is the working process of the above hydrogen engine turbine blade cooling system: Step 1: preliminarily heat the hydrogen fuel through the lubricating oil / hydrogen heat exchanger 4.

[0040] Step 2, the preliminarily preheated hydrogen is passed into the regenerator 5 and heated to a suitable temperature.

[0041] Step 3, passing hydrogen at a suitable temperature into the inner cooling channel 11 of the mid-chord region of the turbine blade to perform efficient convection cooling on the turbine blade and also to reheat the hydrogen.

[0042] Step 4, the hydrogen that has been heated after cooling is passed into the turbine 7 for supercharging to further increase the pressure of the hydrogen.

[0043] Step 5, passing the pressurized hydrogen into the combustion chamber 8 of the hydrogen engine to provide high-efficiency fuel for the hydrogen engine.

[0044] Accordingly, the present application also proposes a hydrogen gas turbine, including a combustion chamber 8 and a turbine 7, and the above-mentioned hydrogen gas turbine turbine blade cooling system. Hydrogen and air are mixed and burned in the combustion chamber 8 to produce high-temperature and high-pressure combustion gas. These gases then drive the turbine 7 to rotate, thereby driving the compressor and other equipment to work. In view of the high-temperature working environment of the turbine blades in the hydrogen gas turbine, the hydrogen gas turbine turbine blade cooling system can effectively cool the turbine blades.

[0045] like Figure 2 As shown, it is a schematic diagram of a turbine blade of the present application, in which a cooling hole 14 is provided at the trailing edge 9 of the blade for air cooling, and an air film hole 13 is provided at the leading edge 10 of the blade for air cooling, and an internal cooling channel 11 is provided in the mid-chord area of ​​the blade between the leading edge 10 and the trailing edge 9 of the blade, and a rib 12 is provided at the bottom of the internal cooling channel 11. The cooling hole 14 allows cooling air to flow out from the inside of the blade and directly act on the surface of the blade, effectively taking away the heat generated by high-speed rotation and high-temperature environment, thereby reducing the working temperature of the blade and extending its service life. The air film hole 13 sprays cooling air at a certain angle and distribution to form a thin air film covering the surface of the blade. This air film not only plays a role in heat insulation, but also reduces the direct scouring of the high-temperature combustion gas on the blade, further protecting the blade from high-temperature erosion.

[0046] like Figure 4 As shown, it is a schematic diagram of a cooling structure type of the cooling channel 11 in the chord area of ​​the hydrogen combustion engine turbine blade. The ribs 12, column ribs and impact holes can be set at the bottom of the cooling channel 11. For example, the ribs 12 are used as the cooling structure of the cooling channel 11 in the chord area of ​​the hydrogen combustion engine turbine blade, and the rib 12 structure is arranged on the upper and lower walls of the channel, and then the shape of the ribs 12 is determined.

[0047] like Figure 5As shown, it is a schematic diagram of the concentrated form of ribs 12, from left to right, straight ribs, inclined ribs, V-shaped ribs and W-shaped ribs. As an example, the ratio of the height to the width of the rib 12 is 1, and the height and width of the rib 12 are equal, which can increase the heat exchange area while maintaining the smooth flow of the fluid in the channel. When the height and width are equal, the rib 12 can provide a more uniform cooling effect and is not easy to cause excessive congestion of the fluid in the channel. The ratio of the height of the rib 12 to the height of the channel ranges from 0.05 to 0.25. This ratio range determines the size of the space occupied by the rib 12 in the channel. A smaller ratio means that the rib 12 is relatively short and has less obstruction to the flow of the fluid, but the heat exchange area is also relatively small. A larger ratio provides a larger heat exchange area, but may increase the flow resistance of the fluid. The ratio of the spacing between the fins 12 to the height of the fins 12 ranges from 3 to 6. The ratio of the spacing between the fins 12 to the height of the fins 12 determines the density between the fins 12. A smaller ratio means that the fins 12 are arranged more densely, which can provide a better heat exchange effect, but may also increase the pressure loss of the fluid. A larger ratio reduces the interference between the fins 12, which is conducive to the smooth flow of the fluid, but the heat exchange effect may be relatively weak. The inclination angle of the fins 12 is 30° to 90°. The inclination angle of the fins 12 refers to the angle between the fins 12 and the bottom of the channel. A smaller inclination angle may be more conducive to the smooth flow of the fluid and reduce the flow resistance, while a larger inclination angle may provide a larger heat exchange area and enhance the cooling effect.

[0048] like Figure 6As shown, it is a schematic diagram of various arrangements of ribs 12. From left to right, they are whole ribs, broken ribs, multiple ribs in sequence and multiple ribs in staggered arrangement. For broken ribs, the ratio of the break spacing to the channel width can range from 0.25 to 0.5. For multiple ribs in sequence and multiple ribs in staggered arrangement, the ratio of the spacing in both directions of the ribs 12 to the height of the ribs 12 can range from 3 to 6. Among them, whole ribs refer to the continuous and unbroken arrangement of the ribs 12 in the channel. This arrangement provides a larger heat exchange area, which is conducive to enhancing the cooling effect. Whole ribs may also increase the flow resistance of the fluid, so it is necessary to balance the cooling efficiency and fluid dynamics performance. Broken ribs refer to the ribs 12 that are broken at a certain spacing in the channel to form a discontinuous rib 12 arrangement. This arrangement can reduce the flow resistance of the fluid while still maintaining a certain heat exchange area. The ratio of the break spacing to the channel width can be adjusted according to the specific cooling requirements and fluid dynamics performance. A larger break spacing helps to reduce the flow resistance, but may reduce the heat exchange efficiency. A smaller break spacing provides a larger heat exchange area, but may increase the flow resistance. Multi-rib sequential arrangement means that multiple fins 12 are arranged in the same direction in the channel. This arrangement is easy to process and manufacture, and the spacing between the fins 12 can be controlled more evenly. The ratio of the spacing between the fins 12 in two directions to the height of the fins 12 can be adjusted to optimize the cooling efficiency and fluid dynamics. A larger spacing helps to reduce flow resistance, but may reduce heat transfer efficiency. A smaller spacing provides a larger heat transfer area, but may increase flow resistance and manufacturing costs. Multi-rib staggered arrangement means that multiple fins 12 are arranged in a staggered manner in the channel. This arrangement can more effectively utilize the channel space, increase the heat transfer area, and may improve the flow characteristics of the fluid. For multi-rib staggered arrangement, the ratio of the spacing between the fins 12 in two directions to the height of the fins 12 is also in the range of 3 to 6. By reasonably adjusting the spacing and arrangement of the fins 12, a higher heat transfer efficiency can be achieved while maintaining a lower flow resistance.

[0049] like Figure 7 As shown, it is a schematic diagram of various fin 12 sizes. It can be divided into large size (the ratio of the fin 12 height to the channel height is greater than 0.25), conventional size (the ratio of the fin 12 height to the channel height is between 0.05 and 0.25) and micro size (the ratio of the fin 12 height to the channel height is less than 0.05). Considering only the heat exchange requirements, the ratio of the fin 12 height to the inner cooling channel 11 height can be greater than 0.25, that is, a large size is used. It is necessary to consider the heat exchange requirements and the hydrogen flow requirements, so that the ratio of the fin 12 height to the inner cooling channel 11 height can be less than 0.05, that is, a micro size is used.

[0050] like Figure 3As shown, in order to verify the effect of the above-mentioned fin 12 structure. After determining the shape of the fin 12, Python programming is used to perform DOE (Design of Experiments) to determine the factors and levels involved in the hydrogen cooling ribbed channel of the hydrogen gas turbine turbine blade, and to develop a calculation example schedule. It should be noted that experimental design is a statistical method used to plan experiments, collect data, and analyze results in order to effectively identify and control key factors that affect the system or process. Python provides a variety of libraries and tools that can assist in DOE.

[0051] Taking the 90° ribbed channel 16 as an example, the high heat transfer performance of hydrogen and the high cooling performance of the inner cooling channel 11 in the mid-chord area of ​​the turbine blade using hydrogen as the cooling medium are verified. Figure 8 As shown, secondary development based on the open source CAD software FreeCAD is used to complete the parametric modeling of the hydrogen cooling ribbed channel 16 of the hydrogen gas engine turbine blade, including the cooling channel solid domain, the cooling structure solid domain and the hydrogen fluid domain; hydrogen enters from the hydrogen inlet, enters the ribbed channel 16 through the rectifying section 15 on the hydrogen inlet side, and then flows out from the rectifying section 15 on the hydrogen outlet side; the ribbed channel 16 has a heating wall 17.

[0052] like Fig. 9 As shown in the figure, a hybrid grid scheme combining multi-block structured grids and unstructured grids is used to carry out the grid division of the hydrogen cooling ribbed channel of the hydrogen gas engine turbine blade, where (a) is the solid domain and (b) is the fluid domain. For component areas with simpler structures, hexahedral structured grids are used to reduce the number of grids. For component areas with complex structures, hybrid grids or polyhedral grids are used to reduce the time cost of grid division, and finally the grid division is carried out reasonably. Among them, the grid division work is completed by the open source software Gmsh. Then, the boundary conditions are set and the numerical calculations are carried out. The Reynolds number at the inlet is 30000, the inlet temperature is 300 K, the outlet pressure is 101 kPa, and the wall heat flux is 3000W·m -2 A preliminary calculation is carried out under the working conditions. Fig.10 As shown in the figure, the open source software ParaView is used to post-process the results of the hydrogen flow and heat transfer in the cooling ribbed channel of the hydrogen gas engine turbine blade, where (a) is the air cooling result and (b) is the hydrogen cooling result. Compared with air cooling, the maximum wall temperature of the hydrogen cooling ribbed channel is reduced by 20.85% (about 83 K), the average wall temperature is reduced by 17.77% (about 67 K), and the wall heat transfer coefficient is increased by 5.93 times. At the same time, the friction coefficient of the hydrogen cooling ribbed channel (about 0.0375) is slightly lower than the friction coefficient of the air cooling ribbed channel (about 0.0398).

[0053] According to the DOE calculation example schedule, a large number of numerical calculations with a wide range of parameters are carried out, and Python programming is used to process and analyze the calculation results, including data cleaning, data completion, normalization, drawing curves, describing the change of cooling performance with each parameter, etc. According to the result data, the machine learning algorithm is used to construct a prediction model for the cooling performance of the hydrogen-cooled ribbed channel of the hydrogen-fired turbine turbine blade and optimize the structural parameters. Among them, the machine learning algorithms used to construct the prediction model include neural networks, decision trees, random forests, support vector machines, etc. The machine learning algorithms used for structural parameter optimization can include genetic algorithms, particle swarm algorithms, simulated annealing algorithms, ant colony algorithms, etc.

[0054] According to the optimization results, the criterion formula for the correlation between the cooling channel performance and the optimal structural parameter combination was fitted, and the design criteria for the hydrogen cooling ribbed channel of hydrogen gas engine turbine blades were summarized.

[0055] It can also be seen from the verification results that hydrogen can not only significantly improve the heat transfer effect, but also save cooling air extracted from the compressor. In addition, hydrogen is the main fuel source for hydrogen engines, making the idea of ​​using hydrogen as a cooling medium for turbine blades feasible.

[0056] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A hydrogen combustion engine turbine blade cooling system, characterized in that: It comprises a hydrogen turbocharger (6), and a first pressure fuel pump (2), a second pressure fuel pump (3), a heat exchanger (4) and a regenerator (5) which are sequentially connected to allow hydrogen to flow through; The inlet of the first pressure fuel pump (2) is connected to a hydrogen source; the first pressure fuel pump (2) and the second pressure fuel pump (3) are used to pressurize the hydrogen in sequence; The heat exchange medium of the heat exchanger (4) is the lubricating oil of the hydrogen combustion engine, which is used to preheat the hydrogen; The heat source of the regenerator (5) is the heat in the high-temperature combustion gas discharged from the hydrogen combustion engine turbine (7). The regenerator (5) is provided with two outlets, the first outlet being connected to the inlet of the inner cooling channel (11) located in the mid-chord area of ​​the turbine blade to be cooled, for secondary preheating of the hydrogen, and the second outlet being connected to the hydrogen turbocharger (6); The outlet of the internal cooling channel (11) located in the mid-chord area of ​​the turbine blade to be cooled is connected to the inlet of the hydrogen turbocharger (6), and the outlet of the hydrogen turbocharger (6) is connected to the combustion chamber (8) of the hydrogen combustion engine. The hydrogen turbocharger (6) is used to pressurize the hydrogen before entering the combustion chamber (8).

2. The hydrogen combustion engine turbine blade cooling system according to claim 1, characterized in that: Ribs (12) are provided on two opposite inner walls of the inner cooling channel (11).

3. The hydrogen combustion engine turbine blade cooling system according to claim 2, characterized in that: The rib (12) is V-shaped.

4. The hydrogen combustion engine turbine blade cooling system according to claim 2, characterized in that: Each of the fins (12) comprises a plurality of sub-fins (12), and gaps are left between adjacent sub-fins (12); the gaps between two adjacent fins (12) are arranged in a staggered manner.

5. The hydrogen combustion engine turbine blade cooling system according to claim 4, characterized in that: The ratio of the distance between two adjacent fins (12) to the height of the fins (12) is in the range of 3 to 6.

6. The hydrogen combustion engine turbine blade cooling system according to claim 2, characterized in that: The dimensions of the fins (12) include: According to the heat exchange requirements, the ratio of the height of the fin (12) to the height of the inner cooling channel (11) is greater than 0.25; Alternatively, in combination with heat exchange requirements and hydrogen flow requirements, the ratio of the height of the fin (12) to the height of the inner cooling channel (11) is made less than 0.

05.

7. The hydrogen combustion engine turbine blade cooling system according to claim 2, characterized in that: The ratio of the height to the width of the fin (12) is 1.

8. The hydrogen combustion engine turbine blade cooling system according to claim 2, characterized in that: The rib (12) is arranged to be inclined relative to the surface on which the rib (12) is installed, and the inclination angle of the rib (12) is 30° to 90°.

9. A hydrogen gas turbine, comprising a combustion chamber (8) and a turbine (7); characterized in that: It also includes the hydrogen combustion engine turbine blade cooling system as described in any one of claims 1 to 8.

10. The hydrogen gas turbine according to claim 9, characterized in that: Air cooling channels are provided on the leading edges (10) and trailing edges (9) of the turbine blades in the turbine (7).

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