Design method of cooling structure of micro-tube array with spherical bulge on moving blade

Abstract

The present invention provides a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array. By constructing the outer shape and internal cooling structure of the turbine moving blade, the position of the turbine moving blade that needs to be enhanced in cooling is determined. An overall three-dimensional model of a turbine moving blade with a spherical bulge micro-tube array cooling structure is constructed, and the amount of cooling air reduction of the turbine moving blade is preset; the turbine moving blade, cooling structure and spherical bulge micro-tube array cooling parameters are adjusted; an overall three-dimensional model of a turbine moving blade with a spherical bulge micro-tube array cooling structure after the blade is thinned is constructed, and full three-dimensional heat-flow coupling calculation of the turbine moving blade is performed to obtain the temperature field distribution information of the turbine moving blade. If the temperature parameters of the turbine moving blade meet the predetermined temperature standards, the design is completed. The technical solution of the present invention can solve the problem that the high-pressure turbine moving blade of a gas turbine is limited by the structural size space and the amount of cooling air used, resulting in uneven temperature distribution of the blade, causing blade ablation, cracks and other faults.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine design, and particularly relates to a design method for a cooling structure of a moving blade with a spherical bulge 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] An embodiment of the present invention provides a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array, which can solve the problem that the moving blade 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 on 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 moving blade with a spherical bulge micro-tube array is provided, comprising:

[0007] S101. Determine the cooling structure of the turbine blade body without a micro-tube array cooling channel according to the appearance of the turbine blade body, perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine blade, and determine the temperature field distribution and data information of the blade body, which will serve as a basis for subsequent analysis and comparison after adopting a design with a spherical bulge micro-tube array cooling structure.

[0008] S102, determining the location of the high temperature area in the turbine rotor blade where the enhanced cooling structure is to be arranged.

[0009] S103, according to the surface structure of the moving blade body, combined with the dimensional parameters of the moving blade body including at least the blade body wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine moving blade body with a spherical bulge micro-tube array are given.

[0010] S104, constructing an overall three-dimensional model of a turbine blade with a spherical bulge micro-tube array cooling structure, and inferring the reduction in cooling air for the turbine blade body and the amount of cooling air used for the turbine blade body with the spherical micro-tube array cooling structure.

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

[0012] S106. Determine the amount of thinning of the turbine blade body based on the ratio of the cooling air usage to the original given cooling air usage.

[0013] S107. Based on the reduction ratio of the cooling channel area inside the turbine blade body and the outer thickness of the blade body, the cooling structure of the turbine blade body is reconstructed, and a three-dimensional model of the turbine blade body and cooling channel after the blade shape is adjusted is established using a three-dimensional modeling tool.

[0014] S108. According to the three-dimensional model of the turbine moving blade body after the blade shape is adjusted and the reduction ratio of the cooling channel area inside the moving blade body, adjust the positions of the micro-spherical tubes in the root section and the top section, the diameter of each circular through tube, the center spacing of the through tubes, the number of spherical bulges in each micro-channel along the blade height direction, the spherical bulge spacing, the diameter of each spherical bulge, and the number of micro-tube channels. The spherical bulge micro-tube array cooling structure parameters.

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

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

[0017] Based on the specific position of the turbine blade body that needs enhanced cooling, the cooling structure parameters of the turbine blade body with a spherical bulge micro-tube array are given; among them, in the root section, the distance H from the position of each micro-tube center along the blade body wall thickness midline to the leading edge point of the blade body wall thickness midline h,i 、The diameter of each circular channel tube φ h,i , Channel tube center distance L h,i ; In the top section, the distance H between the center of each microtube along the midline of the blade thickness and the leading edge of the midline of the blade thickness t,i 、The diameter of each circular channel tube φ t,i , through pipe center distance L t,i ; The number of spherical bulges along the blade height direction in each microchannel M j , Spherical bulge spacing G j,k And the diameter of each spherical bulge ψ j,k , the number of microtubule channels N.

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

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

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

[0021] The temperature field distribution and temperature data of the turbine rotor blade body are compared and analyzed with the temperature field distribution and data information of the rotor blade body without the micro-tube array cooling channel. If the obtained temperature parameters of the turbine rotor blade body meet the predetermined temperature standard, S106 is executed; otherwise, the cooling structure parameters of the spherical bulge micro-tube array are adjusted by at least increasing the number of micro-tube rows or increasing the diameters of the micro-tubes and the spherical bulges, and S104 to S105 are repeatedly executed until the temperature parameters of the turbine rotor blade body reach the predetermined temperature standard.

[0022] Furthermore, the predetermined temperature standard includes:

[0023] If the maximum temperature of the turbine 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 blade body is lower than the temperature resistance grade of the metal material used;

[0024] If the maximum temperature of the turbine 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 blade body is reduced by not less than 20°C.

[0025] Furthermore, the spherical bulge micro-tube array cooling structure has a circular tube diameter between 0.1 mm and 1 mm. The micro-tube array cooperates with the spherical enhanced cooling structure to increase the heat exchange area of ​​the cooling channel, increase the convection heat transfer coefficient, and achieve super cooling of the blade body; at the same time, it cooperates with the leading edge air film cooling of the turbine blade body to achieve full coverage of the cooling of the high-pressure turbine blade body.

[0026] Furthermore, the method comprises:

[0027] The spherical bulge micro-tube array cooling structure is cooled by spreading the micro-tube array over the remaining positions of the blade body except the leading edge, thereby achieving full coverage of the cooling of the high-pressure turbine moving blade blade body, making the blade body temperature distribution more uniform.

[0028] Further, determining the position of the high temperature area in the turbine rotor blade where the enhanced cooling structure is to be arranged includes:

[0029] Based on the temperature field distribution and temperature data of the moving blade body, the location of the high-temperature area of ​​the turbine moving blade body is determined, that is, the specific location of the turbine moving blade body that requires enhanced cooling. Subsequently, a micro-tube array cooling structure with spherical bulges will be arranged in these high-temperature areas.

[0030] 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.

[0031] The beneficial effects brought by the present invention are as follows:

[0032] It can be seen from the above scheme that the embodiment of the present invention provides a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array. By constructing the outer shape and internal cooling structure of the turbine moving blade, the position of the turbine moving blade that needs enhanced cooling is determined. Given the parameters of the spherical bulge micro-tube array cooling structure of the turbine moving blade, an overall three-dimensional model of the turbine moving blade with a spherical bulge micro-tube array cooling structure is constructed, and the cooling air reduction amount of the turbine moving blade is preset; the full three-dimensional fluid-heat coupling calculation and analysis of the turbine moving blade is performed to determine the thinning amount of the turbine moving blade outer shape, and the turbine moving blade, cooling structure and spherical bulge micro-tube array cooling parameters are adjusted; the overall three-dimensional model of the turbine moving blade with a spherical bulge 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 moving blade is performed to obtain the temperature field distribution information of the turbine moving blade. If the temperature parameters of the turbine moving blade meet the predetermined temperature standard, the design of the micro-tube array cooling structure of the turbine moving blade with a spherical bulge is completed. The technical solution of the present invention can solve the problem that the blade body of the high-pressure turbine 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

[0033] Figure 1 A flow chart showing a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to an embodiment of the present invention. DETAILED DESCRIPTION

[0034] 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.

[0035] In order to solve the problem that the blade body of the high-pressure turbine moving blade 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 thus provide a spherical bulge micro-tube array turbine moving blade cooling structure design method suitable for the high-pressure turbine moving blade of a gas turbine, which has the advantages of excellent cooling effect and low cooling air consumption, so as to avoid the problem that the blade over-temperature operation causes the blade to fail and cannot work.

[0036] like Figure 1 As shown, Figure 1 A flow chart showing a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to an embodiment of the present invention.

[0037] In the figure, a design method for a cooling structure of a moving blade with a spherical bulge micro-tube array comprises:

[0038] S101. Determine the cooling structure of the turbine blade body without a micro-tube array cooling channel according to the appearance of the turbine blade body, perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine blade, and determine the temperature field distribution and data information of the blade body, which will serve as a basis for subsequent analysis and comparison after adopting a design with a spherical bulge micro-tube array cooling structure.

[0039] In an embodiment of the present invention, the shape of a turbine rotor blade is constructed. Based on the blade profile obtained by the turbine aerodynamic design, a three-dimensional modeling tool is used to carry out the design of the turbine rotor blade shape structure, and the three-dimensional shape of the turbine rotor blade is constructed. A turbine rotor blade cooling structure without a micro-tube array cooling channel is designed. Based on the three-dimensional shape of the turbine rotor blade, the turbine rotor blade cooling structure design is carried out (the spherical bulge micro-tube array cooling structure design is not carried out for the rotor blade for the time being), and a three-dimensional model of a turbine rotor blade with a blade cooling structure is obtained (without the spherical bulge micro-tube array cooling structure).

[0040] A full three-dimensional fluid-thermal coupling calculation and analysis is performed on the turbine blades. According to the inlet and outlet boundary conditions of the turbine blades, the constructed three-dimensional model of the turbine blade with a blade body cooling structure is imported into the meshing program to divide the fluid domain and solid domain grids 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 blades, and the temperature field distribution and data of the blade body are obtained as a basis for subsequent analysis and comparison after the design of a cooling structure with a spherical bulge micro-tube array.

[0041] S102, determining the location of the high temperature area in the turbine rotor blade where the enhanced cooling structure is to be arranged.

[0042] In an embodiment of the present invention, based on the temperature field distribution and temperature data of the moving blade body, the position of the high temperature area of ​​the turbine moving blade body is determined, that is, the specific position of the turbine moving blade body that needs to be focused on enhanced cooling. Subsequently, spherical bulge micro-tube array cooling structures will be arranged in these high temperature areas.

[0043] S103, according to the surface structure of the moving blade body, combined with the dimensional parameters of the moving blade body including at least the blade body wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine moving blade body with a spherical bulge micro-tube array are given.

[0044] In the embodiment of the present invention, based on the specific position of the turbine rotor blade that needs to be enhanced cooled, according to the thin and slender structure characteristics of the turbine rotor blade, combined with the turbine rotor blade wall thickness, leading edge air film, trailing edge exhaust and other structural dimension parameters, the turbine rotor blade with spherical bulge micro-tube array cooling structure parameters are given: wherein, in the root section, the distance H from the position of each micro-tube center along the blade body wall thickness midline direction to the leading edge point of the blade body wall thickness midline h,i 、The diameter of each circular channel tube φ h,i , Channel tube center distance L h,i ; In the top section, the distance H between the center of each microtube along the midline of the blade thickness and the leading edge of the midline of the blade thickness t,i 、The diameter of each circular channel tube φ t,i , through pipe center distance L t,i ; The number of spherical bulges along the blade height direction in each microchannel M j , Spherical bulge spacing G j,k以及 The diameter of each spherical bulge ψ j,k , the number of microtubule channels N.

[0045] S104, constructing a three-dimensional model of a turbine blade with a spherical bulge micro-tube array cooling structure, and inferring the reduction in cooling air for the turbine blade body and the amount of cooling air used for the turbine blade body after the spherical bulge micro-tube array cooling structure is installed.

[0046] In an embodiment of the present invention, a three-dimensional model of a turbine blade with a cooling structure is based on the blade body (without a spherical bulge micro-tube array cooling structure), using given parameters of the turbine blade blade body spherical bulge micro-tube array cooling structure, a three-dimensional modeling tool is adopted, and the mixing function is used to mix the root section and top section micro-tube array channels, and a circular micro-tube row is constructed on the turbine blade body. On this basis, a spherical bulge structure is added using the rotation function to obtain a three-dimensional model of a turbine blade with a spherical bulge micro-tube array cooling structure.

[0047] According to the given parameters of the spherical bulge micro-tube array cooling structure of the turbine moving blade, its heat exchange cooling effect is evaluated. Based on this, the reduction in cooling air for the turbine moving blade and the amount of cooling air used for the turbine moving blade with the spherical bulge micro-tube array cooling structure are preliminarily inferred.

[0048] S105. Based on the overall three-dimensional model of the turbine moving blade with a spherical bulge micro-tube array cooling structure, the fluid domain and solid domain grids required for full three-dimensional calculation are divided, and the turbine moving blade is subjected to full three-dimensional fluid-thermal coupling calculation and analysis to obtain the temperature field distribution and temperature data of the moving blade body.

[0049] In the embodiment of the present invention, based on the reduction in cooling air and combined with the other inlet and outlet boundary conditions of the turbine blades, the three-dimensional model of the blade body constructed in step six is ​​imported into the meshing program to divide the full three-dimensional calculation grid, and then the full three-dimensional heat-flow coupling calculation and analysis program is used to carry out the full three-dimensional heat-flow coupling calculation and analysis of the turbine blade body to obtain the temperature distribution of the blade body and related temperature data.

[0050] The temperature field distribution and temperature data of the turbine moving blade body are compared and analyzed with the temperature field distribution and data information of the moving blade body. If the obtained temperature parameters of the turbine moving blade body meet the predetermined temperature standard, S106 is executed; otherwise, the cooling structure parameters of the spherical bulge microtube array are adjusted by at least increasing the number of microtube rows or increasing the diameters of the microtubes and the spherical bulges, and S104 to S105 are repeatedly executed until the temperature parameters of the turbine moving blade body reach the predetermined temperature standard.

[0051] Wherein, the predetermined temperature standard includes:

[0052] If the maximum temperature of the turbine 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 blade body is lower than the temperature resistance grade of the metal material used;

[0053] If the maximum temperature of the turbine 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 blade body is reduced by not less than 20°C.

[0054] S106. Determine the amount of thinning of the turbine blade body based on the ratio of the cooling air usage to the original given cooling air usage.

[0055] In an embodiment of the present invention, the ratio of the cooling air usage to the original given cooling air usage is, that is, the ratio of the reduction in the area of ​​the cooling channel inside the turbine blade body; on the basis of the original internal cooling channel of the turbine blade body, a new internal cooling channel of the turbine blade body is obtained by reducing the internal cooling channel, keeping the wall thickness of the blade body unchanged, and the wall thickness of the blade body is offset outward in the new internal cooling channel of the turbine blade body 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 the blade body shape thinning amount.

[0056] S107. Based on the reduction ratio of the cooling channel area inside the turbine blade body and the outer thickness of the blade body, the cooling structure of the turbine blade body is reconstructed, and a three-dimensional model of the turbine blade body and cooling channel after the blade shape is adjusted is established using a three-dimensional modeling tool.

[0057] S108. According to the three-dimensional model of the turbine moving blade body after the blade shape is adjusted and the reduction ratio of the cooling channel area inside the moving blade body, adjust the positions of the micro-spherical tubes in the root section and the top section, the diameter of each circular through tube, the center spacing of the through tubes, the number of spherical bulges in each micro-channel along the blade height direction, the spherical bulge spacing, the diameter of each spherical bulge, and the number of micro-tube channels. The spherical bulge micro-tube array cooling structure parameters.

[0058] In the embodiment of the present invention, based on the given parameters of the cooling structure of the spherical bulge micro-tube array of the turbine rotor blade, the positions of the micro-spherical tubes at the root section and the top section are adjusted according to the parameters such as the chord length of the adjusted blade profile (H h,i , H t,i ), diameter of each circular channel tube (φ h,i ,φ t,i ), channel tube center distance (L h,i , L t,i ), the number of spherical bulges in each microchannel along the blade height direction is M j , Spherical bulge spacing G j,k 、The diameter of each spherical bulge is ψ j,k , the number of microtube channels N and other cooling structure parameters of the spherical bulge microtube array.

[0059] S109. Construct a three-dimensional model of the turbine blade with a spherical bulge micro-tube array cooling structure after the blade body is thinned, perform full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body, and obtain the temperature field distribution and temperature data of the blade body; if the temperature parameters of the turbine blade body meet the predetermined temperature standard, the design process ends; otherwise, adjust the thinning amount of the turbine blade body shape and the parameters of the spherical bulge micro-tube array cooling structure, and repeat S106 to S108 until the temperature parameters of the turbine blade body reach the predetermined standard.

[0060] In an embodiment of the present invention, based on the three-dimensional model of the turbine rotor blade body, using the given parameters of the turbine rotor blade body spherical bulge micro-tube array cooling structure, a three-dimensional modeling tool is adopted, and the mixing function is utilized to mix the root section and top section micro-tube array channels, and a circular micro-tube row is constructed on the turbine rotor blade body. On this basis, a spherical bulge structure is added using the rotation function, and an overall three-dimensional model of the turbine rotor blade with a spherical bulge micro-tube array cooling structure after the blade body is thinned is constructed. According to the given cooling air consumption and in combination with the other inlet and outlet boundary conditions of the turbine blade, the constructed overall three-dimensional model of the turbine blade with a spherical bulge micro-tube array cooling structure after the blade body is thinned 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-heat coupling calculation and analysis program is used to carry out the full three-dimensional fluid-heat coupling calculation and analysis of the turbine blade body to obtain the temperature field distribution and temperature data of the blade body. If the obtained temperature parameters of the turbine blade body meet the predetermined temperature standard, the design process ends. If it does not meet the predetermined standard, the thinning amount of the turbine blade body shape and the cooling structure parameters of the spherical bulge micro-tube array are adjusted (increase the number of micro-tube rows, increase the diameters of micro-tubes and spherical bulges).

[0061] In the embodiment of the present invention, the spherical bulge micro-tube array cooling structure is cooled, and the diameter of the circular tube is between 0.1mm and 1mm. The micro-tube array with a smaller diameter, combined with the spherical enhanced cooling structure, is beneficial to multiply the heat exchange area of ​​the cooling channel, and at the same time multiply the convective heat transfer coefficient, thereby achieving super cooling of the blade body. Combined with the air film cooling at the leading edge of the blade body, full coverage of the cooling of the high-pressure turbine moving blade can be achieved to meet the cooling requirements of the blade body.

[0062] In an embodiment of the present invention, the spherical bulge micro-tube array cooling structure is arranged inside the metal wall of the blade body to achieve 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 reducing the blade profile loss of the moving blade and improving the aerodynamic performance of the moving blade, 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.

[0063] In another embodiment of the present invention, the cooling of the spherical bulge micro-tube array cooling structure fully utilizes the advantages of the spherical bulge micro-tube array with excellent cooling effect and large heat exchange area, and cooperates with the internal cavity convection heat exchange to meet the cooling needs of the blade body. Therefore, the air film cooling of the rear part of the blade grid can be eliminated.

[0064] The turbine blade body spherical bulge micro-tube array cooling can deliver cooling air to any position of the blade body by reducing the diameter of the circular tube of the micro-tube array, thereby achieving precise customized delivery of blade body cooling needs. Combined with the spherical bulge enhanced cooling structure, the high-temperature area of ​​the blade body can be cooled in a targeted manner.

[0065] In another embodiment of the present invention, the turbine moving blade blade body spherical bulge micro-tube array cooling can be parametrically designed with only a small number of parameters, which is conducive to rapid optimization and adjustment to obtain the best cooling solution, thereby realizing the design process of spherical bulge micro-tube array cooling.

[0066] In another embodiment of the present invention, the turbine moving blade blade body is cooled by a spherical bulge micro-tube array, and the film hole cooling structure of the moving blade blade body is eliminated, which is beneficial to weaken the impact of the blade blade film cooling on the mainstream, reduce mixing losses, and improve turbine efficiency.

[0067] In another embodiment of the present invention, the turbine moving blade is cooled by a spherical bulge micro-tube array, which fully utilizes the excellent cooling effect of the spherical bulge micro-tube array structure, reduces the amount of cooling air used for the blade, and is beneficial to improving the performance of the turbine and the entire gas turbine unit and increasing the efficiency of the unit.

[0068] In another embodiment of the present invention, the turbine moving blade body is cooled by a spherical bulge micro-tube array, the thickness of the moving blade body is thinned, and a cooling tube array channel is arranged inside the blade wall thickness, which can reduce the weight of the moving blade by about 8%.

[0069] In yet another embodiment of the present invention, the three-dimensional modeling software is UG NX software, the full three-dimensional fluid-thermal coupling calculation and analysis software is CFX and Fluent software, and the meshing program is ICEM CFD software.

[0070] The present invention proposes a method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array, which is universal and not only limited to the design of high-pressure turbine moving blades of gas turbines, but is also applicable to the design of high-pressure turbine moving blades of aircraft engines.

[0071] The present invention proposes a method for designing a cooling structure of a turbine moving blade with a spherical bulge micro-tube array. On the basis of making full use of the full three-dimensional fluid-heat coupling calculation method of conventional turbine moving blades, according to the structural characteristics of the high-pressure turbine moving blade of a gas turbine, the method focuses on the high-temperature zone of the high-pressure turbine moving blade, reorganizes the cooling structure design and temperature field calculation process of the moving blade, and proposes a method for designing a cooling structure of a spherical bulge micro-tube array suitable for the high-pressure turbine moving blade of a gas turbine, obtains a method for designing an efficient cooling structure of the high-pressure turbine moving blade, and solves the problem that the high-pressure turbine moving blade of a gas turbine is difficult to cool.

[0072] The present invention proposes a method for designing a cooling structure of a turbine moving blade with a spherical bulge micro-tube array, which can multiply the heat exchange area and convection heat transfer coefficient of the cooling channel through a micro-tube array with a smaller diameter (0.1mm to 1mm), thereby achieving super cooling of the blade. Not only can it achieve full coverage of the cooling of the high-pressure turbine moving blade, but it can also fully meet the cooling requirements of the blade. Therefore, it effectively solves 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, and can effectively solve the problem of overheating and even ablation of the blade. The cooling air is delivered to any position of the moving blade through the small-scale spherical bulge micro-tube array cooling structure, thereby achieving precise customized delivery of the cooling requirements of the blade, so that the high-temperature area of ​​the blade can be focused on in a targeted manner, meeting the local cooling requirements of the moving blade.

[0073] 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 moving blade, thereby reducing the influence of the film cooling of the blade on the mainstream, which is beneficial to reducing the cold and hot mixing loss of the turbine moving blade and improving the turbine efficiency. The technical solution of the present invention fully utilizes the excellent cooling effect of the spherical bulge micro-tube array structure, can reduce the amount of cooling air used for the blade, is beneficial to improve the performance of the turbine and the entire gas turbine unit, and improve the unit efficiency. The designed moving blade has a thinner profile, and a micro-pipeline is arranged inside the wall thickness, which is beneficial to reducing the weight of the moving blade and improving the power-to-weight ratio of the engine.

[0074] 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 moving blade with a spherical bulge micro-tube array, characterized in that: The design method comprises: S101. Determine the cooling structure of the turbine blade body without a micro-tube array cooling channel according to the shape of the turbine blade body, perform full three-dimensional fluid-heat coupling calculation and analysis on the turbine blade, and determine the temperature field distribution and data information of the blade body, which will serve as a comparison basis for subsequent analysis and the use of a design with a spherical bulge micro-tube array cooling structure; S102, determining the position of the high temperature area in the turbine rotor blade where the enhanced cooling structure is to be arranged; S103, according to the surface structure of the moving blade body, combined with the size parameters of the moving blade body including at least the blade body wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine moving blade body with a spherical bulge micro-tube array are given; S104, constructing a three-dimensional model of a turbine blade with a spherical bulge micro-tube array cooling structure, and inferring the reduction in cooling air for the turbine blade and the amount of cooling air used for the turbine blade with the spherical bulge micro-tube array cooling structure; S105. Based on the three-dimensional model of the turbine moving blade with the spherical bulge micro-tube array cooling structure, the fluid domain and solid domain grids required for the full three-dimensional calculation are divided, and the full three-dimensional fluid-heat coupling calculation and analysis of the turbine moving blade are performed to obtain the temperature field distribution and temperature data of the moving blade body; S106, determining an amount of thinning of a turbine blade body based on a ratio of the cooling air usage to an originally given cooling air usage; S107, based on the reduction ratio of the cooling channel area inside the turbine rotor blade body and the thickness of the blade body, reconstruct the cooling structure of the turbine rotor blade body, and use a three-dimensional modeling tool to establish a three-dimensional model of the turbine rotor blade body and the cooling channel after the blade shape is adjusted; S108, adjusting the positions of the micro-spherical tubes in the root section and the top section, the diameter of each circular through tube, the center spacing of the through tubes, the number of spherical bulges in each micro-channel along the blade height direction, the spherical bulge spacing, the diameter of each spherical bulge, and the number of micro-channel channels of the spherical bulge micro-tube array cooling structure parameters according to the three-dimensional model of the turbine rotor blade body after the blade profile is adjusted and the reduction ratio of the cooling channel area inside the rotor blade body; S109. Construct a three-dimensional model of the turbine blade with a spherical bulge micro-tube array cooling structure after the blade body is thinned, perform full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body, and obtain the temperature field distribution and temperature data of the blade body; if the temperature parameters of the turbine blade body meet the predetermined temperature standard, the design process ends; otherwise, adjust the thinning amount of the turbine blade body shape and the parameters of the spherical bulge micro-tube array cooling structure, and repeat S106 to S108 until the temperature parameters of the turbine blade body reach the predetermined standard.

2. The method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to claim 1, characterized in that: According to the surface structure of the moving blade body, combined with the size parameters of the moving blade body including at least the blade body wall thickness, the leading edge air film structure, and the trailing edge exhaust structure, the cooling structure parameters of the turbine moving blade body with a spherical bulge micro-tube array are given, including: Based on the specific position of the turbine blade body that needs enhanced cooling, the cooling structure parameters of the turbine blade body with a spherical bulge micro-tube array are given; among them, in the root section, the distance H from the position of each micro-tube center along the blade body wall thickness midline to the leading edge point of the blade body wall thickness midline h,i 、The diameter of each circular channel tube φ h,i , Channel tube center distance L h,i ; In the top section, the distance H between the center of each microtube along the midline of the blade thickness and the leading edge of the midline of the blade thickness t,i 、The diameter of each circular channel tube φ t,i , through pipe center distance L t,i ; The number of spherical bulges along the blade height direction in each microchannel M j , Spherical bulge spacing G j,k And the diameter of each spherical bulge ψ j,k , the number of microtubule channels N.

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

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

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

6. The method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to claim 1, characterized in that: The spherical bulge micro-tube array cooling structure is cooled, and the diameter of the round tube is between 0.1mm and 1mm. The micro-tube array cooperates with the spherical enhanced cooling structure to increase the heat exchange area of ​​the cooling channel, increase the convection heat transfer coefficient, and achieve super cooling of the blade body; at the same time, it cooperates with the leading edge air film cooling of the turbine blade body to achieve full coverage of the cooling of the high-pressure turbine blade body.

7. The method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to claim 1, characterized in that: The method comprises: The spherical bulge micro-tube array cooling structure is cooled by spreading the micro-tube array over the remaining positions of the blade body except the leading edge, thereby achieving full coverage of the cooling of the high-pressure turbine moving blade blade body, making the blade body temperature distribution more uniform.

8. The method for designing a cooling structure of a moving blade with a spherical bulge micro-tube array according to claim 1, characterized in that: Determining the location of the high temperature area in the turbine rotor blade where the enhanced cooling structure is to be arranged includes: Based on the temperature field distribution and temperature data of the moving blade body, the location of the high-temperature area of ​​the turbine moving blade body is determined, that is, the specific location of the turbine moving blade body that requires enhanced cooling. Subsequently, a micro-tube array cooling structure with spherical bulges will be arranged in these high-temperature areas.

9. The method for designing a cooling structure of a moving blade with a spherical bulge 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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