Design method of cooling structure of guide vane with circular micro-tube array

Abstract

The present invention provides a method for designing a cooling structure of a guide vane with a circular micro-tube array. By constructing the outer shape and internal cooling structure of a turbine guide vane, the position of the turbine guide vane to be enhanced is determined. An overall three-dimensional model of a turbine guide vane with a circular micro-tube array cooling structure is constructed, and the amount of cooling air reduction of the turbine guide vane is preset; the amount of thinning of the outer shape is determined, and the cooling parameters of the turbine guide vane, cooling structure and circular micro-tube array are adjusted; an overall three-dimensional model of a turbine guide vane with a circular micro-tube array cooling structure after the blade is thinned is constructed, and full three-dimensional fluid-heat coupling calculation and analysis are performed. If the temperature parameters of the turbine guide vane meet the predetermined standards, the design is completed. The technical solution of the present invention can solve the problem that the high-pressure turbine guide vane of a gas turbine is limited by the structural size space and the amount of cooling air, resulting in uneven temperature distribution of the blade, causing faults such as blade ablation and cracking, and avoids the failure of the blade to work due to over-temperature operation of the blade.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine design, and in particular relates to a cooling structure design method of a guide vane blade body with a circular micro-tube array. Background Art

[0002] With the continuous improvement of gas turbine performance indicators and the continuous expansion of their operating boundaries, the turbine inlet temperature continues to increase, which puts higher requirements on the temperature resistance grade of turbine blade materials and cooling structure design for long-term continuous operation under high load conditions.

[0003] During the operation of existing engines and the development of new engines, there are areas in turbine blades that are difficult to cool, especially the end walls and blade tops with relatively small dimensions and relatively complex flows, which are prone to forming cooling "blind spots" or even "dead spots". The metal temperatures at these locations are close to the heat resistance limit of the blade alloy. Similar phenomena have also been reported by foreign researchers when conducting gas turbine design and testing. The surface temperature distribution of turbine blades obtained by transient liquid crystal measurement and numerical calculation by Siemens and other companies shows that obvious local high-temperature areas appear at the blade body, end wall and blade top. These local high-temperature areas that are difficult to cool can easily cause local ablation of turbine blades, which brings great difficulties to the cooling design of turbine blades. In addition, with the expansion of the engine use environment and the improvement of performance requirements, the turbine inlet temperature continues to increase, further increasing the design difficulty of the turbine blade cooling structure.

[0004] Therefore, when traditional large-scale cooling structures are unable to meet the cooling needs of "blind spots" and "dead spots", innovating and developing efficient cooling structures for turbine blades can further improve the cooling effect without increasing the amount of cold air used, which has important scientific significance and practical value for the development of advanced high-performance gas turbine engines. Summary of the invention

[0005] The embodiment of the present invention provides a method for designing a cooling structure of a guide vane with a circular micro-tube array, which can solve the problem that the guide vane of a high-pressure turbine of a gas turbine is limited by the structural size space and the amount of cooling air, resulting in uneven temperature distribution of the blade body, causing blade ablation, cracks and other faults, and avoid over-temperature operation of the blade, which causes the blade to fail and be unable to work.

[0006] In an embodiment of the present invention, a method for designing a cooling structure of a guide vane blade with a circular micro-tube array is provided, comprising:

[0007] S101. Determine the cooling structure of the turbine guide vane without a micro-tube array cooling channel according to the appearance of the turbine guide vane, perform full three-dimensional fluid-thermal coupling calculation and analysis on the turbine guide vane, and determine the temperature field distribution and data information of the guide vane as a basis for subsequent analysis and comparison after adopting a circular micro-tube array cooling structure design;

[0008] S102, determining the position of the high temperature area in the turbine guide vane blade where the enhanced cooling structure is to be arranged;

[0009] S103, according to the surface structure of the guide vane blade, combined with the size parameters of the guide vane blade including at least the blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine guide vane blade with a circular micro-tube array are given;

[0010] S104, constructing an overall three-dimensional model of a turbine guide vane with a circular micro-tube array cooling structure, and inferring a reduction in cooling air for the turbine guide vane blade body and an amount of cooling air for the turbine guide vane blade body after the circular micro-tube array cooling structure is provided;

[0011] S105. Based on the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure, the fluid domain and solid domain grids required for full three-dimensional calculation are divided, and full three-dimensional fluid-thermal coupling calculation and analysis are carried out to obtain the temperature field distribution and temperature data of the guide vane blade body;

[0012] S106, determining the thinning amount of the turbine guide vane blade body based on the ratio of the cooling air reduction amount to the original given cooling air usage amount;

[0013] S107, based on the reduction ratio of the cooling channel area inside the turbine guide vane blade body and the outer thickness of the blade body, reconstruct the cooling structure of the turbine guide vane blade body, and use a three-dimensional modeling tool to establish a three-dimensional model of the turbine guide vane blade body and the cooling channel after the blade shape is adjusted;

[0014] S108, adjusting the position of the micro circular tubes in the root section and the top section, the diameter of each circular micro tube, the diameter of each circular micro tube, the spacing between the circular micro tubes, and the number of the circular micro tubes according to the three-dimensional model of the turbine guide vane body after the blade profile is adjusted and the reduction ratio of the cooling channel area inside the guide vane body;

[0015] S109. Construct an overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure after the blade body is thinned, perform full three-dimensional heat-flow coupling calculation and analysis on the turbine guide vane blade body, and obtain the temperature field distribution and temperature data of the guide vane blade body; if the temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, the design process ends; otherwise, adjust the thinning amount of the turbine guide vane blade body and the parameters of the circular micro-tube array cooling structure, and repeat S106 to S108 until the temperature parameters of the turbine guide vane blade body reach the predetermined standard.

[0016] Further, according to the surface structure of the guide vane blade, combined with the size parameters of the guide vane blade including at least the blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine guide vane blade with a circular micro-tube array are given, including:

[0017] Based on the specific position of the turbine guide vane that needs enhanced cooling, according to the thin and slender structural characteristics of the turbine guide vane, combined with the size parameters of at least the turbine guide vane wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the turbine guide vane blade with circular micro-tube array cooling structure parameters are given; wherein, in the root section, the distance H from the position of each circular micro-tube along the center line of the blade wall thickness to the leading edge point of the center line of the blade wall thickness is h,i 、Each circular microtube diameter φ h,i 、Circular microtube spacing L h,i , the number of circular microtubes N; in the top section, the distance from the position of each circular microtube along the midline of the blade thickness to the leading edge point of the midline of the blade thickness H t,i 、Each circular microtube diameter φ t,i 、Circular microtube spacing L t,i , the number of circular microtubules N.

[0018] Further, based on the ratio of the cooling air reduction amount to the original given cooling air usage amount, the thinning amount of the turbine guide vane blade is determined, including:

[0019] The ratio of the cooling air reduction amount to the original given cooling air usage is, that is, the reduction ratio of the cooling channel area inside the turbine guide vane blade body; on the basis of the original turbine guide vane blade body internal cooling channel, a new turbine guide vane blade body internal cooling channel is obtained by reducing the channel, keeping the guide vane blade body wall thickness unchanged, and the guide vane blade body wall thickness is offset outward in the new turbine guide vane blade body internal cooling channel to obtain the blade body shape thickness after adjusting the internal cooling channel, and the difference between the blade body shape thickness after adjusting the internal cooling channel and the thickness before adjustment is, that is, the blade body shape thinning amount.

[0020] Furthermore, based on the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure, the fluid domain and solid domain meshes required for full three-dimensional calculation are divided to obtain the temperature field distribution and temperature data of the guide vane body, including:

[0021] The temperature field distribution and temperature data of the turbine guide vane blade body are compared and analyzed with the temperature field distribution and data information of the guide vane blade body. If the obtained temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, S106 is executed; otherwise, the circular microtube array cooling structure parameters are adjusted by at least increasing the number of microtube rows or increasing the diameter of the microtubes, and S104 to S105 are repeatedly executed until the temperature parameters of the turbine guide vane blade body reach the predetermined temperature standard.

[0022] Furthermore, the predetermined temperature standard includes:

[0023] If the maximum temperature of the turbine guide vane blade body is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used;

[0024] If the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is reduced by not less than 20°C.

[0025] Furthermore, the circular micro-tube array cooling structure has a circular tube diameter between 0.3 mm and 0.5 mm. The micro-tube array structure can increase the heat exchange area of ​​the cooling channel and increase the convective heat transfer coefficient; at the same time, it cooperates with the leading edge film cooling of the turbine guide vane blade body to achieve full coverage of the cooling of the high-pressure turbine guide vane blade body.

[0026] Furthermore, the method comprises:

[0027] The circular micro-tube array cooling structure is arranged inside the metal wall of the blade body to reduce the thickness of the guide vane blade body profile.

[0028] Furthermore, the method comprises:

[0029] The circular micro-tube array cooling structure is distributed all over the guide vane blade except the leading edge, thereby achieving full coverage of the cooling of the high-pressure turbine guide vane blade, so that the temperature of the turbine guide vane blade is evenly distributed.

[0030] Further, determining the position of the high temperature area in the turbine guide vane blade where the enhanced cooling structure is to be arranged comprises:

[0031] Based on the temperature field distribution and temperature data of the guide vane blade body, the location of the high-temperature area of ​​the turbine guide vane blade body is determined, that is, the specific location of the turbine guide vane blade body that needs to be focused on and enhanced cooling. Subsequently, a circular micro-tube array cooling structure will be arranged in these high-temperature areas.

[0032] Furthermore, UG NX software is used as the three-dimensional modeling software for the computational domain, CFX and Fluent software are used as the full three-dimensional fluid-thermal coupling calculation and analysis software, and ICEM CFD software is used for meshing.

[0033] The beneficial effects brought by the present invention are as follows:

[0034] It can be seen from the above scheme that the embodiment of the present invention provides a cooling structure design method for a guide vane with a circular micro-tube array. By constructing the outer shape and internal cooling structure of a turbine guide vane, a cooling structure of a turbine guide vane without a micro-tube array cooling channel is designed, and the position of the turbine guide vane that needs enhanced cooling is determined. Given the parameters of the circular micro-tube array cooling structure of the turbine guide vane, an overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure is constructed, and the cooling air reduction amount of the turbine guide vane is preset; the full three-dimensional fluid-heat coupling calculation and analysis of the turbine guide vane is performed to determine the thinning amount of the turbine guide vane outer shape, and the turbine guide vane, cooling structure and circular micro-tube array cooling parameters are adjusted; the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure after the blade is thinned is constructed, and the full three-dimensional fluid-heat coupling calculation and analysis of the turbine guide vane is performed to obtain the temperature field distribution information of the turbine guide vane. If the temperature parameters of the turbine guide vane meet the predetermined temperature standard, the design of the micro-tube array cooling structure of the turbine guide vane with a circular bulge is completed. The technical solution of the present invention can solve the problem that the blade body of the high-pressure turbine guide vane of the gas turbine is limited by the structural size space and the amount of cooling air used, resulting in uneven temperature distribution of the blade body, causing blade ablation, cracks and other faults, and avoid over-temperature operation of the blade, which causes the blade to fail and unable to work. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 A flow chart showing a method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] like Figure 1 As shown, Figure 1 A flow chart showing a method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to an embodiment of the present invention.

[0038] In the figure, a cooling structure design method for a guide vane blade with a circular micro-tube array includes:

[0039] S101. Determine the cooling structure of the turbine guide vane without a micro-tube array cooling channel according to the appearance of the turbine guide vane, perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine guide vane, and determine the temperature field distribution and data information of the guide vane, which will serve as a basis for subsequent analysis and comparison after adopting a circular micro-tube array cooling structure design.

[0040] In the embodiment of the present invention, the turbine guide vane blade shape is constructed, and on the basis of the blade profile obtained by the turbine aerodynamic design, a three-dimensional modeling tool is used to carry out the turbine guide vane blade shape structure design, and the three-dimensional shape of the turbine guide vane blade is constructed. The turbine guide vane blade cooling structure without the micro-tube array cooling channel is designed, and on the basis of the three-dimensional shape of the turbine guide vane blade, the turbine guide vane blade cooling structure design is carried out (the guide vane blade does not carry out the circular micro-tube array cooling structure design for the time being), and a three-dimensional model of the turbine guide vane with a blade cooling structure is obtained (without the circular micro-tube array cooling structure).

[0041] A full three-dimensional fluid-thermal coupling calculation and analysis is performed on the turbine guide vanes. According to the inlet and outlet boundary conditions of the turbine guide vanes (including the amount of cooling air), the constructed three-dimensional model of the turbine guide vanes with a blade cooling structure is imported into the meshing program to divide the fluid domain and solid domain meshes required for the full three-dimensional calculation. Then, the full three-dimensional fluid-thermal coupling calculation and analysis program is used to carry out the full three-dimensional fluid-thermal coupling calculation and analysis of the turbine guide vanes, and the temperature field distribution and data of the turbine guide vane blade body are obtained as a basis for subsequent analysis and comparison after the design with a circular micro-tube array cooling structure.

[0042] S102, determining the position of the high temperature area in the turbine guide vane blade where the enhanced cooling structure is to be arranged.

[0043] In an embodiment of the present invention, based on the temperature field distribution and temperature data of the guide vane blade body, the position of the high temperature area of ​​the turbine guide vane blade body is determined, that is, the specific position of the turbine guide vane blade body that needs to be focused on enhanced cooling, and subsequently, circular micro-tube array cooling structures will be arranged in these high temperature areas.

[0044] S103, according to the surface structure of the guide vane blade, combined with the dimensional parameters of the guide vane blade including at least the blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine guide vane blade with a circular micro-tube array are given.

[0045] In an embodiment of the present invention, based on determining the specific position where the turbine guide vane blade needs enhanced cooling, according to the structural characteristics of the slender thickness of the turbine guide vane blade, combined with structural size parameters such as the turbine guide vane blade wall thickness, leading edge air film, and trailing edge exhaust, the cooling structural parameters of the circular microtube array of the turbine guide vane blade are given: the number of circular microtubes; in the root section, the position of each circular microtube along the centerline of the blade body wall thickness (the distance to the leading edge point of the centerline of the blade body wall thickness), the diameter of each circular microtube, and the spacing between the circular microtubes; in the top section, the position of each circular microtube along the centerline of the blade body thickness (the distance to the leading edge point of the centerline of the blade body thickness), and the diameter of each circular microtube.

[0046] In one embodiment of the present invention, based on the specific position of the turbine guide vane blade that needs enhanced cooling, according to the thin and slender structural characteristics of the turbine guide vane blade, combined with at least the size parameters of the turbine guide vane blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the turbine guide vane blade with circular micro-tube array cooling structure parameters is given; wherein, in the root section, the distance H from the position of each circular micro-tube along the blade body wall thickness midline direction to the leading edge point of the blade body wall thickness midline h,i 、Each circular microtube diameter φ h,i 、Circular microtube spacing L h,i , the number of circular microtubes N; in the top section, the distance from the position of each circular microtube along the midline of the blade thickness to the leading edge point of the midline of the blade thickness H t,i 、Each circular microtube diameter φ t,i 、Circular microtube spacing L t,i , the number of circular microtubules N.

[0047] S104, constructing an overall three-dimensional model of a turbine guide vane with a circular micro-tube array cooling structure, and inferring the reduction in cooling air for the turbine guide vane blade body and the amount of cooling air for the turbine guide vane blade body with the circular micro-tube array cooling structure.

[0048] In an embodiment of the present invention, based on a three-dimensional model of a turbine guide vane with a cooling structure on a blade body (without a circular micro-tube array cooling structure), using given circular micro-tube array cooling structure parameters of a turbine guide vane blade body, a three-dimensional modeling tool is adopted to mix the circular micro-tube arrays of the root section and the top section, and a circular micro-tube row is constructed on the turbine guide vane blade body to obtain an overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure; according to the given circular micro-tube array cooling structure parameters of the turbine guide vane blade body, the heat exchange cooling effect is evaluated, and based on this, the reduction in cooling air of the turbine guide vane blade body and the amount of cooling air used for the turbine guide vane blade body with the circular micro-tube array cooling structure are preliminarily inferred.

[0049] S105. Based on the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure, the fluid domain and solid domain grids required for full three-dimensional calculations are divided, and full three-dimensional fluid-thermal coupling calculation and analysis are carried out to obtain the temperature field distribution and temperature data of the guide vane blade body.

[0050] According to the given cooling air reduction and combined with the other inlet and outlet boundary conditions of the turbine guide vane, the constructed overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure is imported into the meshing program to divide the fluid domain and solid domain meshes required for the full three-dimensional calculation. Then, the full three-dimensional fluid-thermal coupling calculation and analysis program is used to carry out the full three-dimensional fluid-thermal coupling calculation and analysis of the turbine guide vane blade body, and the temperature field distribution and temperature data of the turbine guide vane blade body are obtained.

[0051] The temperature field distribution and temperature data of the turbine guide vane blade body are compared and analyzed with the temperature field distribution and data information of the guide vane blade body. If the obtained temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, S106 is executed; otherwise, the circular microtube array cooling structure parameters are adjusted by at least increasing the number of microtube rows or increasing the diameter of the microtubes, and S104 to S105 are repeatedly executed until the temperature parameters of the turbine guide vane blade body reach the predetermined temperature standard.

[0052] Wherein, the predetermined temperature standard includes:

[0053] If the maximum temperature of the turbine guide vane blade body is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used;

[0054] If the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is reduced by not less than 20°C.

[0055] S106. Determine the amount of thinning of the turbine guide vane blade body based on the ratio of the cooling air reduction amount to the original given cooling air usage amount.

[0056] In the embodiment of the present invention, based on the ratio of the determined cooling air reduction amount to the original given cooling air usage, this ratio is the reduction ratio of the cooling channel area inside the turbine guide vane blade body. According to this ratio, on the basis of the original turbine guide vane blade body internal cooling channel, a new turbine guide vane blade body internal cooling channel is obtained by reducing the original turbine guide vane blade body internal cooling channel, keeping the guide vane blade body wall thickness unchanged, and the guide vane blade body wall thickness is offset outward in the new turbine guide vane blade body internal cooling channel to obtain the blade body external thickness after adjusting the internal cooling channel. The difference between the blade body external thickness after adjusting the internal cooling channel and the thickness before adjustment is the blade body external thinning amount.

[0057] S107. Based on the reduction ratio of the cooling channel area inside the turbine guide vane blade body and the outer thickness of the blade body, the cooling structure of the turbine guide vane blade body is reconstructed, and a three-dimensional model of the turbine guide vane blade body and the cooling channel after the blade shape is adjusted is established using a three-dimensional modeling tool.

[0058] In an embodiment of the present invention, based on the constructed guide vane blade cooling structure, the turbine guide vane blade cooling structure is reconstructed according to the determined reduction ratio of the internal cooling channel area of ​​the turbine guide vane blade and the blade body outer thickness, and a three-dimensional modeling tool is used to establish a three-dimensional model of the turbine guide vane blade and cooling channel after adjusting the blade shape.

[0059] S108. According to the three-dimensional model of the turbine guide vane body after the blade shape is adjusted and the reduction ratio of the cooling channel area inside the guide vane body, adjust the position of the root section and the top section micro-circular tubes, the diameter of each circular micro-tube, the diameter of each circular micro-tube, the spacing between the circular micro-tubes and the number of the circular micro-tubes.

[0060] S109. Construct an overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure after the blade body is thinned, perform full three-dimensional heat-flow coupling calculation and analysis on the turbine guide vane blade body, and obtain the temperature field distribution and temperature data of the guide vane blade body; if the temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, the design process ends; otherwise, adjust the thinning amount of the turbine guide vane blade body and the parameters of the circular micro-tube array cooling structure, and repeat S106 to S108 until the temperature parameters of the turbine guide vane blade body reach the predetermined standard.

[0061] In an embodiment of the present invention, according to a given cooling air consumption and in combination with other inlet and outlet boundary conditions of the turbine guide vane, the constructed overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure after the blade body is thinned is imported into a meshing program, and the fluid domain and solid domain meshes required for the full three-dimensional calculation are divided. Then, the full three-dimensional fluid-thermal coupling calculation and analysis program is used to carry out the full three-dimensional fluid-thermal coupling calculation and analysis of the turbine guide vane blade body, and the temperature field distribution and temperature data of the guide vane blade body are obtained.

[0062] In one embodiment of the present invention, the circular micro-tube array cooling structure is used for cooling, and the diameter of the circular tube is between 0.3 mm and 0.5 mm. The micro-tube array structure can increase the heat exchange area of ​​the cooling channel and increase the convective heat transfer coefficient; at the same time, it cooperates with the leading edge film cooling of the turbine guide vane blade body to achieve full coverage of the high-pressure turbine guide vane blade body cooling and meet the blade body cooling requirements.

[0063] In yet another embodiment of the present invention, the circular micro-tube array cooling structure is arranged inside the metal wall of the blade body to reduce the thickness of the guide vane blade body profile.

[0064] The circular micro-tube array cooling structure is arranged inside the metal wall of the blade body, which realizes one-time efficient cooling of the blade body. The cooling demand inside the blade body will be reduced, and the original internal cooling cavity can be reduced, that is, the thickness of the blade body profile can be thinned, which is not only beneficial to improving the aerodynamic performance of the guide vane, but also can reduce the heated area of ​​the blade body, which is beneficial to further reduce the cooling demand and comprehensively reduce the cooling air consumption.

[0065] In another embodiment of the present invention, the circular micro-tube array cooling structure is distributed all over the guide vane blade except the leading edge, thereby achieving full coverage of the cooling of the high-pressure turbine guide vane blade, so that the temperature of the turbine guide vane blade is evenly distributed.

[0066] The circular micro-tube array cooling structure is used for cooling. It covers the rest of the blade except the leading edge through the smaller micro-tube array. It can not only achieve full coverage of the cooling of the high-pressure turbine guide vane blade, but also make the temperature distribution of the blade more uniform. The problem of uneven temperature causing large thermal stress due to traditional blade film plus convection cooling will no longer exist.

[0067] The circular micro-tube array cooling structure cooling fully utilizes the advantages of excellent cooling effect and large heat exchange area of ​​the micro-tube array, and cooperates with the internal cavity convection heat exchange to meet the cooling requirements of the blade body. Therefore, the air film cooling of the middle and rear parts of the blade grid can be eliminated. The circular micro-tube array cooling of the turbine guide vane blade body can reduce the diameter of the micro-tube array circular tube and deliver the cooling air to any position of the guide vane blade body, thereby realizing the precise customized delivery of the blade body cooling requirements, and can cool the high temperature area of ​​the blade body in a targeted manner.

[0068] In the embodiment of the present invention, the circular micro-tube array cooling of the turbine guide vane blade body can realize the parametric design of the circular micro-tube array cooling of the guide vane blade body through only a small number of parameters, which is conducive to rapid optimization and adjustment to obtain the best cooling solution. The circular micro-tube array cooling of the turbine guide vane blade body cancels the film hole cooling structure of the guide vane blade body part, which is conducive to reducing the influence of the blade body film cooling on the mainstream, reducing mixing losses, and improving turbine efficiency.

[0069] The circular micro-tube array cooling of the turbine guide vane blade makes full use of the excellent cooling effect of the circular micro-tube array structure, reduces the amount of cooling air used for the blade body, and is beneficial to improving the performance of the turbine and the entire gas turbine unit and improving the unit efficiency. Among them, the circular micro-tube array cooling of the turbine guide vane blade body, the thickness of the guide vane blade body is thinned, and the cooling tube array channel is arranged inside the blade wall thickness, which can reduce the weight of the guide vane by about 8%.

[0070] The circular micro-tube array cooling design method for the guide vane blade body proposed in the present invention is universal and is not limited to the design of high-pressure turbine guide vanes of gas turbines, but is also applicable to the design of high-pressure turbine guide vanes of aircraft engines.

[0071] In another embodiment of the present invention, the computational domain three-dimensional modeling software adopts UG NX software, the full three-dimensional fluid-heat coupling calculation and analysis software adopts CFX and Fluent software, and the meshing adopts ICEM CFD software.

[0072] In the embodiment of the present invention, on the basis of making full use of the full three-dimensional fluid-heat coupling calculation method of the conventional turbine guide vane, according to the structural characteristics of the high-pressure turbine guide vane blade body of the gas turbine, focusing on the high-temperature area of ​​the high-pressure turbine guide vane blade body, the guide vane blade body cooling structure design and temperature field calculation process are reorganized, and a circular micro-tube array cooling design method suitable for the high-pressure turbine guide vane blade body of the gas turbine is proposed. An efficient cooling structure design method for the high-pressure turbine guide vane blade body is obtained, which solves the problem that the high-pressure turbine guide vane blade body of the gas turbine is difficult to cool.

[0073] Through the use of micro-tube arrays with smaller diameters (0.3mm to 0.5mm), the heat exchange area and convection heat transfer coefficient of the cooling channel are multiplied, thereby achieving super cooling of the blade body. Not only can full coverage of high-pressure turbine guide vane cooling be achieved, but also the cooling requirements of the blade body can be fully met. Therefore, the problem of "blind spots" and "dead spots" that are difficult to cool due to the limitations of the spatial structure of traditional air film and large-scale cooling can be effectively solved, and the problem of overheating and even ablation of the blade body can be effectively solved. The cooling air is delivered to any position of the guide vane blade body through a small-scale circular micro-tube array cooling structure, thereby achieving precise customized delivery of the cooling requirements of the blade body, so that the high-temperature area of ​​the blade body can be cooled in a targeted manner, meeting the local cooling requirements of the guide vane blade body.

[0074] The technical solution of the present invention can give full play to the better cooling effect of the micro-tube array, cancel the film hole cooling structure in the middle and rear sections of the guide vane blade, thereby reducing the influence of the blade film cooling on the mainstream, which is beneficial to reducing the cold and hot mixing loss of the turbine guide vane blade and improving the turbine efficiency. By making full use of the excellent cooling effect of the circular micro-tube array structure, the amount of cooling air for the blade can be reduced, which is beneficial to improving the performance of the turbine and the entire gas turbine unit and improving the unit efficiency. The designed guide vane blade line is thin, and a micro-pipeline is arranged inside the wall thickness, which is beneficial to reducing the weight of the guide vane and improving the power-to-weight ratio of the engine.

[0075] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for designing a cooling structure of a guide vane with a circular micro-tube array, characterized in that: The design method comprises: S101. Determine the cooling structure of the turbine guide vane without a micro-tube array cooling channel according to the appearance of the turbine guide vane, perform full three-dimensional fluid-thermal coupling calculation and analysis on the turbine guide vane, and determine the temperature field distribution and data information of the guide vane as a basis for subsequent analysis and comparison after adopting a circular micro-tube array cooling structure design; S102, determining the position of the high temperature area in the turbine guide vane blade where the enhanced cooling structure is to be arranged; S103, according to the surface structure of the guide vane blade, combined with the size parameters of the guide vane blade including at least the blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine guide vane blade with a circular micro-tube array are given; S104, constructing an overall three-dimensional model of a turbine guide vane with a circular micro-tube array cooling structure, and inferring a reduction in cooling air for the turbine guide vane blade body and an amount of cooling air for the turbine guide vane blade body after the circular micro-tube array cooling structure is provided; S105. Based on the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure, the fluid domain and solid domain grids required for full three-dimensional calculation are divided, and full three-dimensional fluid-thermal coupling calculation and analysis are carried out to obtain the temperature field distribution and temperature data of the guide vane blade body; S106, determining the amount of thinning of the turbine guide vane blade body based on the ratio of the cooling air reduction amount to the original given cooling air usage amount; S107, based on the reduction ratio of the cooling channel area inside the turbine guide vane blade body and the outer thickness of the blade body, reconstruct the cooling structure of the turbine guide vane blade body, and use a three-dimensional modeling tool to establish a three-dimensional model of the turbine guide vane blade body and the cooling channel after the blade shape is adjusted; S108, adjusting the position of the micro circular tubes in the root section and the top section, the diameter of each circular micro tube, the diameter of each circular micro tube, the spacing between the circular micro tubes, and the number of the circular micro tubes according to the three-dimensional model of the turbine guide vane body after the blade profile is adjusted and the reduction ratio of the cooling channel area inside the guide vane body; S109. Construct an overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure after the blade body is thinned, perform full three-dimensional heat-flow coupling calculation and analysis on the turbine guide vane blade body, and obtain the temperature field distribution and temperature data of the guide vane blade body; if the temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, the design process ends; otherwise, adjust the thinning amount of the turbine guide vane blade body and the parameters of the circular micro-tube array cooling structure, and repeat S106 to S108 until the temperature parameters of the turbine guide vane blade body reach the predetermined standard.

2. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: According to the surface structure of the guide vane blade, combined with the size parameters of the guide vane blade including at least the blade wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine guide vane blade with a circular micro-tube array are given, including: Based on the specific position of the turbine guide vane that needs enhanced cooling, according to the thin and slender structural characteristics of the turbine guide vane, combined with the size parameters of at least the turbine guide vane wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the turbine guide vane blade with circular micro-tube array cooling structure parameters are given; wherein, in the root section, the distance H from the position of each circular micro-tube along the center line of the blade wall thickness to the leading edge point of the center line of the blade wall thickness is h,i 、Each circular microtube diameter φ h,i 、Circular microtube spacing L h,i , the number of circular microtubes N; in the top section, the distance from the position of each circular microtube along the midline of the blade thickness to the leading edge point of the midline of the blade thickness H t,i 、Each circular microtube diameter φ t,i 、Circular microtube spacing L t,i , the number of circular microtubules N.

3. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: Based on the ratio of the cooling air reduction to the original given cooling air usage, determine the thinning amount of the turbine guide vane blade, including: The ratio of the cooling air reduction amount to the original given cooling air usage is, that is, the reduction ratio of the cooling channel area inside the turbine guide vane blade body; on the basis of the original turbine guide vane blade body internal cooling channel, a new turbine guide vane blade body internal cooling channel is obtained by reducing the channel, keeping the guide vane blade body wall thickness unchanged, and the guide vane blade body wall thickness is offset outward in the new turbine guide vane blade body internal cooling channel to obtain the blade body shape thickness after adjusting the internal cooling channel, and the difference between the blade body shape thickness after adjusting the internal cooling channel and the thickness before adjustment is, that is, the blade body shape thinning amount.

4. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: Based on the overall three-dimensional model of the turbine guide vane with a circular micro-tube array cooling structure, the fluid domain and solid domain meshes required for full three-dimensional calculation are divided, and full three-dimensional fluid-thermal coupling calculation and analysis are carried out to obtain the temperature field distribution and temperature data of the guide vane blade body, including: The temperature field distribution and temperature data of the turbine guide vane blade body are compared and analyzed with the temperature field distribution and data information of the turbine guide vane blade body without the micro-tube array cooling channel. If the obtained temperature parameters of the turbine guide vane blade body meet the predetermined temperature standard, S106 is executed; otherwise, the circular micro-tube array cooling structure parameters are adjusted by at least increasing the number of micro-tube rows or increasing the diameter of the micro-tubes, and S104 to S105 are repeatedly executed until the temperature parameters of the turbine guide vane blade body reach the predetermined temperature standard.

5. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 4, characterized in that: The predetermined temperature standard includes: If the maximum temperature of the turbine guide vane blade body is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used; If the maximum temperature of the turbine guide vane blade body is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine guide vane blade body is reduced by not less than 20°C.

6. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: The circular micro-tube array cooling structure has a circular tube diameter between 0.3 mm and 0.5 mm. The micro-tube array structure can increase the heat exchange area of ​​the cooling channel and increase the convective heat transfer coefficient. At the same time, it cooperates with the leading edge air film cooling of the turbine guide vane blade body to achieve full coverage of the high-pressure turbine guide vane blade body cooling.

7. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: The method comprises: The circular micro-tube array cooling structure is arranged inside the metal wall of the blade body to reduce the thickness of the guide vane blade body profile.

8. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: The method comprises: The circular micro-tube array cooling structure is distributed all over the guide vane blade except the leading edge, thereby achieving full coverage of the cooling of the high-pressure turbine guide vane blade, so that the temperature of the turbine guide vane blade is evenly distributed.

9. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: Determining the location of the high temperature area in the turbine guide vane blade where the enhanced cooling structure is to be arranged comprises: Based on the temperature field distribution and temperature data of the guide vane blade body, the location of the high-temperature area of ​​the turbine guide vane blade body is determined, that is, the specific location of the turbine guide vane blade body that needs to be focused on and enhanced cooling. Subsequently, a circular micro-tube array cooling structure will be arranged in these high-temperature areas.

10. The method for designing a cooling structure of a guide vane blade with a circular micro-tube array according to claim 1, characterized in that: The 3D modeling software of the computational domain adopts UG NX software, the full 3D fluid-heat coupling calculation and analysis software adopts CFX and Fluent software, and the meshing adopts ICEM CFD software.

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