Design method of cooling structure of turbine blade edge plate with spherical bulge micro-tube array

Abstract

The present invention provides a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array. The method determines the cooling structure of the turbine blade body and performs full three-dimensional heat-flow coupling calculation and analysis. The method determines the position of the high-temperature zone in the turbine blade edge plate where the spherical bulge micro-tube array cooling structure is to be arranged, and gives the cooling structure parameters. The method constructs a three-dimensional model of a turbine blade with a cooling structure of a spherical bulge micro-tube array in a transverse single row on the edge plate and a blade body with a cooling structure, and performs full three-dimensional heat-flow coupling calculation on the edge plate. The method performs full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body and the edge plate as a whole. If the temperature parameters of the turbine blade meet the predetermined temperature standard, the design is completed. The technical solution of the present invention can solve the problem that the blade edge plate of the high-pressure turbine of a gas turbine is affected by the lateral secondary flow in the end area and is limited by the space of the structural size, so that the cooling air is difficult to cover, resulting in ablation of the blade edge plate, and avoids the problem that the blade operates at an over-temperature and causes the blade to fail to work.

Description

Technical Field

[0001] The invention belongs to the technical field of gas turbine design, and particularly relates to a design method for a turbine blade edge plate cooling structure 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 for a turbine blade edge plate with a spherical bulge micro-tube array, which can solve the problem that the blade edge plate of a high-pressure turbine of a gas turbine is affected by the lateral secondary flow in the end area and is limited by the structural size space, making it difficult for cooling air to cover it, resulting in ablation of the blade edge plate, thereby avoiding the problem of over-temperature operation of the turbine blades, which causes the turbine blades to fail and become unable to work.

[0006] In an embodiment of the present invention, a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array is provided, comprising:

[0007] S101, determining the cooling structure of the turbine rotor blade body, performing full three-dimensional fluid-heat coupling calculation and analysis on the turbine rotor blade, obtaining the temperature distribution and data of the turbine rotor blade edge plate, and determining that the temperature parameters of the turbine rotor blade body meet the predetermined temperature standard;

[0008] S102, determining the position of the high temperature area in the turbine blade edge plate where the spherical bulge micro-tube array cooling structure is to be arranged according to the temperature field distribution and data of the turbine blade edge plate;

[0009] S103, according to the surface structure of the moving blade edge plate, combined with the structural dimension parameters of the moving blade edge plate including at least thickness, width, and length, a transverse single-row spherical bulge micro-tube array cooling structural parameter is given;

[0010] S104, a micro-tube array with spherical bulges is arranged on the rotor blade edge plate, and a three-dimensional model of a turbine rotor blade having a cooling structure of a micro-tube array with a transverse single row of spherical bulges on the edge plate is constructed;

[0011] S105, extracting a three-dimensional model of a turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure, and performing full three-dimensional fluid-thermal coupling calculation and analysis on the three-dimensional model of the turbine blade edge plate to obtain temperature field distribution and data of the turbine blade edge plate;

[0012] S106, if the temperature parameter of the turbine blade edge plate meets the predetermined temperature standard, the next step is executed; otherwise, the cooling structure parameter of the transverse single-row spherical bulge micro-tube array is adjusted, and S103 to S105 are repeatedly executed until the temperature parameter of the turbine blade edge plate reaches the predetermined temperature standard;

[0013] S107. Perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body and edge plate as a whole to obtain the temperature field distribution information of the turbine blade with a spherical bulge micro-tube array cooling structure on the edge plate. If the temperature parameter of the turbine blade meets the predetermined temperature standard, the design of the turbine blade edge plate cooling structure with a spherical bulge micro-tube array is completed; otherwise, repeat the above steps until the temperature parameter of the turbine blade reaches the predetermined temperature standard.

[0014] Furthermore, a full three-dimensional fluid-heat coupling calculation and analysis is performed on the turbine blades to obtain the temperature distribution and data of the turbine blade edge plate, and determine the temperature distribution of the turbine blade body, including:

[0015] Construct a three-dimensional model of turbine blades, divide the fluid domain and solid domain grids required for full three-dimensional calculations, perform full three-dimensional fluid-thermal coupling calculations and analysis of turbine blades, and obtain the temperature field distribution and data of turbine blade edge plates;

[0016] Obtain the convection heat transfer coefficient h of the turbine blade edge plate flow surface r,yb and convection heat transfer As boundary conditions for subsequent analysis;

[0017] If the temperature parameter of the turbine blade body meets the predetermined temperature standard, that is, the maximum temperature T of the turbine blade body Rblade,maxLower than the temperature resistance grade T of the metal material used R-M , T Rblade,max <T R-M , then execute S102; otherwise, re-determine the cooling structure of the turbine rotor blade body until the temperature parameter of the turbine rotor blade body reaches a predetermined standard.

[0018] Furthermore, the cooling structure parameters of the transverse single-row spherical bulge micro-tube array include:

[0019] The position of the center line of the micro-spherical tubes arranged along the thickness direction of the moving blade edge plate, the position of the center line of the micro-spherical tubes arranged along the width direction of the moving blade edge plate, the number of micro-spherical tube rows arranged along the width direction of the moving blade edge plate, the tube diameter and length of each micro-tube row, and the path of each micro-tube arranged along the length direction of the moving blade edge plate;

[0020] Among them, the position of the center line of the micro-spherical tube arranged along the thickness direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the flow surface of the edge plate; the position of the center line of the micro-spherical tube arranged along the width direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the side of the edge plate; the diameter of the micro-tube row includes the diameter of the through tube and the diameter of the spherical bulge.

[0021] Furthermore, a three-dimensional model of a turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure is extracted, and a full three-dimensional fluid-thermal coupling calculation and analysis is performed on the three-dimensional model of the turbine blade edge plate to obtain the temperature field distribution information of the turbine blade edge plate, including:

[0022] Meshing is performed on the three-dimensional model of the turbine moving blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure of the edge plate, and the fluid domain and solid domain meshes required for full three-dimensional calculation are divided. Based on the temperature field distribution and data of the turbine moving blade edge plate, the Nusselt number of the turbine moving blade edge plate convective heat transfer, the convective heat transfer coefficient of the turbine moving blade edge plate, and the cooling air flow rate, the cooling air inlet and outlet temperature and pressure boundary conditions, a full three-dimensional fluid-heat coupling calculation and analysis of the turbine moving blade edge plate is performed to obtain the temperature field distribution and data of the moving blade edge plate;

[0023] The Nusselt number is:

[0024]

[0025] The convective heat transfer coefficient is:

[0026]

[0027] The cooling air flow rate is:

[0028]

[0029] Among them, Reynolds number Re=uD / ν, rotation number Ro=ΩD / u, density ratio DR=α v (T w -T c ), u is the fluid velocity at the microtube inlet, ν is the fluid kinematic viscosity coefficient, D is the straight tube diameter, Ω is the rotation speed, α v is the volume expansion coefficient, T w is the microtube wall temperature, L is the straight tube length, C1, C2, C3, C4 are flow heat transfer power indexes, n qg is the number of spherical bulges per microtube, d q is the diameter of the spherical bulge, m is the total mass flow rate of the microtube array, Q r,yb is the heat transferred from the gas to the edge plate, Cp is the constant pressure specific heat capacity of the cold gas, T g is the gas temperature on the edge plate side, h g is the convective heat transfer coefficient of the gas on the edge plate side, A is the heat transfer area on the gas side of the edge plate, T c is the cooling air inlet temperature of the microtube array, h c is the convective heat transfer coefficient of the cooling air, n is the number of microtubes, and λ is the thermal conductivity of the cooling air.

[0030] Furthermore, the temperature parameter of the turbine blade edge plate meets the predetermined temperature standard, including:

[0031] If the maximum temperature of the turbine blade edge plate is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used; if the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is reduced by no less than 10°C.

[0032] Further, adjusting the cooling structure parameters of the transverse single-row spherical bulge microtube array includes:

[0033] The distance from the center line of the micro-spherical tube to the flow surface of the moving blade edge plate is reduced, the number of the micro-tube rows is increased, the diameter of the micro-tubes in the micro-tube rows is increased, and the number of spherical bulges in each micro-tube row is increased.

[0034] Furthermore, the diameter of the cooling circular tube section of the spherical bulge micro-tube array cooling structure is 0.1 mm to 1 mm, and the diameter of the spherical bulge is 1.5 to 2 times the diameter of the cooling circular tube section.

[0035] Furthermore, the turbine blade edge plate is cooled by a transverse single-row spherical bulge micro-tube array, which reduces the circular tube diameter of the micro-tube array and delivers cooling air to any position of the turbine blade edge plate, thereby achieving precise customized delivery of the turbine blade edge plate cooling requirements and targeted cooling of the high-temperature area of ​​the turbine blade edge plate.

[0036] 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.

[0037] The beneficial effects brought by the present invention are as follows:

[0038] It can be seen from the above scheme that an embodiment of the present invention provides a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array. By determining the cooling structure of the turbine blade body, the temperature parameters of the turbine blade body are determined to meet the predetermined temperature standard; the position of the high-temperature zone in the turbine blade edge plate where the spherical bulge micro-tube array cooling structure is to be arranged is determined, and the cooling structure parameters of the transverse single-row spherical bulge micro-tube array are given; a three-dimensional model of a turbine blade with a cooling structure of a transverse single-row spherical bulge micro-tube array on the edge plate and a blade body with a cooling structure is constructed; the three-dimensional model of the turbine blade edge plate is subjected to full three-dimensional heat-flow coupling calculation and analysis to obtain the temperature field distribution information of the turbine blade edge plate; the turbine blade body and the edge plate are subjected to full three-dimensional heat-flow coupling calculation and analysis as a whole to obtain the temperature field distribution information of the turbine blade. If the temperature parameters of the turbine blade meet the predetermined temperature standard, the design of the cooling structure of the turbine blade edge plate with the spherical micro-tube array is completed. The technical solution of the present invention can solve the problem that the blade edge plate of the high-pressure turbine of the gas turbine is affected by the lateral secondary flow in the end area and the structural size space is limited, which makes it difficult for cooling air to cover, resulting in ablation of the blade edge plate, thereby avoiding the problem of blade over-temperature operation, which causes the blade to fail and unable to work. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A flow chart showing a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge microtube array according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] 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.

[0041] In order to solve the problem that the high-pressure turbine moving blade edge plate of a gas turbine is affected by the lateral secondary flow in the end area and the structural size and space are limited, the cooling air is difficult to cover, resulting in blade edge ablation, and thus a design method for a turbine moving blade edge plate cooling structure with a lateral single-row spherical bulge micro-tube array suitable for gas turbine high-pressure turbine moving blades and having excellent cooling effect is provided to avoid the problem that the blades fail to work due to over-temperature operation.

[0042] like Figure 1 As shown, Figure 1 A flow chart showing a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge microtube array according to an embodiment of the present invention.

[0043] In the figure, a design method for a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array includes:

[0044] S101, determining the cooling structure of the turbine rotor blade body, performing full three-dimensional fluid-heat coupling calculation and analysis on the turbine rotor blade, obtaining the temperature distribution and data of the turbine rotor blade edge plate, and determining that the temperature parameters of the turbine rotor blade body meet the predetermined temperature standard.

[0045] In an embodiment of the present invention, based on the appearance obtained by the turbine aerodynamic design, a turbine moving blade body cooling structure design is carried out, wherein the moving blade edge plate does not temporarily carry out cooling structure design such as film cooling, and a moving blade body cooling structure is obtained.

[0046] According to the inlet and outlet boundary conditions of the turbine blades, a three-dimensional model of the turbine blades is constructed, and the fluid domain and solid domain grids required for full three-dimensional calculations are divided. The full three-dimensional fluid-thermal coupling calculation and analysis of the turbine blades are performed to obtain the temperature field distribution and data of the turbine blade edge plate, which serves as a basis for subsequent analysis and comparison after adopting the spherical bulge micro-tube array cooling design;

[0047] Obtain the convection heat transfer coefficient h of the turbine blade edge plate flow surface r,yb and convection heat transfer It serves as the boundary condition for subsequent analysis.

[0048] If the temperature parameter of the turbine blade body meets the predetermined temperature standard, that is, the maximum temperature T of the turbine blade body Rblade,max Lower than the temperature resistance grade T of the metal material used R-M , T Rblade,max <T R-M , then execute S102; otherwise, re-determine the cooling structure of the turbine rotor blade body until the temperature parameter of the turbine rotor blade body reaches a predetermined standard.

[0049] S102, determining the location of the high temperature area in the turbine blade edge plate where the spherical bulge micro-tube array cooling structure is to be arranged according to the temperature field distribution and data of the turbine blade edge plate.

[0050] In the embodiment of the present invention, specific locations on the turbine blade edge plate that require enhanced cooling will subsequently be provided with a micro-tube array cooling structure with spherical bulges at these high-temperature locations.

[0051] S103. According to the surface structure of the moving blade edge plate and in combination with the structural dimension parameters of the moving blade edge plate including at least thickness, width and length, a cooling structural parameter of a transverse single-row spherical bulge micro-tube array is given.

[0052] In the embodiment of the present invention, based on the specific position of the turbine moving blade edge plate that needs to be cooled, according to the structural characteristics of the turbine moving blade edge plate surface that is approximately parallelogram, combined with the structural dimension parameters such as the thickness, width, and length of the moving blade edge plate, the cooling structural parameters of the transverse single-row spherical micro-tube array are given: the position of the center line of the micro-spherical tubes arranged along the thickness direction of the moving blade edge plate, the position of the center line of the micro-spherical tubes arranged along the width direction of the moving blade edge plate, the number of micro-spherical tube rows arranged along the width direction of the moving blade edge plate, the tube diameter and length of each micro-tube row, and the path of each micro-tube arranged along the length direction of the moving blade edge plate;

[0053] Among them, the position of the center line of the micro-spherical tube arranged along the thickness direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the flow surface of the edge plate; the position of the center line of the micro-spherical tube arranged along the width direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the side of the edge plate; the diameter of the micro-tube row includes the diameter of the through tube and the diameter of the spherical bulge.

[0054] S104, arranging spherical micro-tube rows and spherical bulges on the blade edge plate, and constructing a three-dimensional model of a turbine blade with a blade edge plate having a cooling structure of a micro-tube array with a single row of spherical bulges in the transverse direction of the blade edge plate.

[0055] In an embodiment of the present invention, based on a three-dimensional model of a turbine moving blade, a spherical micro-tube row is arranged on the moving blade edge plate using given parameters of a transverse single-row spherical micro-tube array cooling structure, and a three-dimensional model of a turbine moving blade with a transverse single-row spherical bulge micro-tube array cooling structure on the edge plate and a blade body with a cooling structure is constructed.

[0056] S105, extracting a three-dimensional model of a turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure, and performing a full three-dimensional fluid-thermal coupling calculation and analysis on the three-dimensional model of the turbine blade edge plate to obtain the temperature field distribution and data of the turbine blade edge plate.

[0057] S106. If the temperature parameter of the turbine blade edge plate meets the predetermined temperature standard, execute the next step; otherwise, adjust the cooling structure parameters of the transverse single-row spherical bulge micro-tube array, and repeat S103 to S105 until the temperature parameter of the turbine blade edge plate reaches the predetermined temperature standard.

[0058] In an embodiment of the present invention, a three-dimensional model of a turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure is meshed, and the fluid domain and solid domain meshes required for full three-dimensional calculation are divided. Based on the temperature field distribution and data of the turbine blade edge plate, the Nusselt number of the turbine blade edge plate convective heat transfer, the convective heat transfer coefficient of the turbine blade edge plate, and the cooling air flow rate, the cooling air inlet and outlet temperature and pressure boundary conditions, a full three-dimensional fluid-heat coupling calculation and analysis of the turbine blade edge plate is performed to obtain the temperature field distribution and data of the blade edge plate.

[0059] The Nusselt number is:

[0060]

[0061] The convective heat transfer coefficient is:

[0062]

[0063] The cooling air flow rate is:

[0064]

[0065] Among them, Reynolds number Re=uD / ν, rotation number Ro=ΩD / u, density ratio DR=α v (T w -T c ), u is the fluid velocity at the microtube inlet, ν is the fluid kinematic viscosity coefficient, D is the straight tube diameter, Ω is the rotation speed, α v is the volume expansion coefficient, T w is the microtube wall temperature, L is the straight tube length, C1, C2, C3, C4 are flow heat transfer power indexes, n qg is the number of spherical bulges per microtube, d q is the diameter of the spherical bulge, m is the total mass flow rate of the microtube array, Q r,yb is the heat transferred from the gas to the edge plate, Cp is the constant pressure specific heat capacity of the cold gas, T g is the gas temperature on the edge plate side, h g is the convective heat transfer coefficient of the gas on the edge plate side, A is the heat transfer area on the gas side of the edge plate, T c is the cooling air inlet temperature of the microtube array, h c is the convective heat transfer coefficient of the cooling air, n is the number of microtubes, and λ is the thermal conductivity of the cooling air.

[0066] If the maximum temperature of the turbine blade edge plate is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used; if the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is reduced by no less than 10°C.

[0067] In an embodiment of the present invention, the cooling structure parameters of the transverse single-row spherical bulge microtube array are adjusted, including: reducing the distance from the center line of the microspherical tube to the flow surface of the moving blade edge plate, increasing the number of the microtube rows, increasing the diameter of the microtubes in the microtube rows, and increasing the number of spherical bulges in each microtube row.

[0068] S107. Perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body and edge plate as a whole to obtain the temperature field distribution information of the turbine blade with a spherical bulge micro-tube array cooling structure on the edge plate. If the temperature parameter of the turbine blade meets the predetermined temperature standard, the design of the turbine blade edge plate cooling structure with a spherical bulge micro-tube array is completed; otherwise, repeat the above steps until the temperature parameter of the turbine guide blade reaches the predetermined temperature standard.

[0069] In the embodiment of the present invention, the diameter of the cooling circular tube section of the spherical bulge micro-tube array cooling structure is 0.1mm to 1mm, and the diameter of the spherical tube is 1.5 to 2 times the diameter of the circular tube section. The micro-tube array with a smaller diameter, combined with the spherical bulge to strengthen the cooling structure, is conducive to doubling the heat exchange area of ​​the cooling channel and doubling the convective heat transfer coefficient, thereby achieving super cooling of the edge plate. Obviously, through the micro-tube array structure with a spherical bulge, not only can the full coverage of the high-pressure turbine moving blade edge plate cooling be achieved, but also the edge plate cooling requirements can be fully met. Therefore, the edge plate air film cooling can be cancelled, and the problem that the traditional edge plate air film cooling is affected by the lateral secondary flow in the end area and the space structure is limited, resulting in the air film being difficult to cover the cooling "dead zone" will no longer exist, and the cooling and cooling requirements of the high-pressure turbine moving blade edge plate of the gas turbine can be more easily met.

[0070] In another embodiment of the present invention, the turbine blade edge plate is cooled by a transverse single-row spherical bulge micro-tube array. By reducing the diameter of the circular tubes of the micro-tube array (to a minimum of 0.1 mm), the cooling air is delivered to any position of the blade edge plate, thereby achieving precise customized delivery to meet the cooling needs of the edge plate, and enhanced cooling is achieved through smaller-scale spherical pipes (to a minimum of 0.2 mm), so that the high-temperature area of ​​the edge plate can be cooled in a targeted manner.

[0071] In the embodiment of the present invention, the cooling structure of the film holes of the blade edge plate is eliminated, which is conducive to reducing the influence of the edge plate film cooling on the mainstream, reducing mixing loss and improving turbine efficiency. In addition, the interior of the blade edge plate is a hollow structure, which can reduce the weight of the blade by 2%.

[0072] 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.

[0073] 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 conventional turbine moving blades, according to the structural characteristics of the high-pressure turbine moving blade edge plate of the gas turbine, the high-temperature zone of the high-pressure turbine moving blade edge plate is focused on, and the moving blade edge plate cooling structure design and temperature field calculation process are reorganized, and a horizontal single-row spherical bulge micro-tube array cooling design method suitable for the moving blade edge plate of the high-pressure turbine of the gas turbine is proposed, and a high-efficiency cooling structure design method for the moving blade edge plate of the high-pressure turbine is obtained, which solves the problem that the moving blade edge plate of the high-pressure turbine of the gas turbine is difficult to cool. Through the micro-tube row with a smaller diameter (0.1mm-1mm), the spherical bulge strengthens the cooling structure, and the heat exchange area and convection heat transfer coefficient of the cooling channel are doubled, thereby realizing super cooling of the edge plate. It can not only achieve full coverage of the cooling of the high-pressure turbine blade edge plate, but also fully meet the edge plate cooling requirements. Therefore, the edge plate air film cooling can be eliminated, which effectively solves the problem of cooling "dead zone" that is difficult to be covered by the air film in the traditional air film cooling structure due to the influence of the end zone lateral secondary flow and spatial structure limitations near the edge plate. This can effectively solve the problem of blade edge plate ablation.

[0074] In the embodiment of the present invention, the cooling air is delivered to any position of the blade edge plate through the spherical bulge micro-tube array, which can realize the precise customized delivery of the edge plate cooling needs, and focus on cooling the high-temperature area of ​​the edge plate in a targeted manner, meeting the local cooling and temperature reduction needs of the blade edge plate. The technical scheme of the present invention can give full play to the better cooling effect of the spherical bulge micro-tube array, eliminate the film hole cooling structure of the blade edge plate, thereby reducing the influence of the edge plate film cooling on the mainstream, which is beneficial to reduce the cold and hot mixing loss of the turbine blade edge plate and improve the turbine efficiency.

[0075] The impeller blade cooling structure designed by the technical solution of the present invention directly discharges cooling air through the rear side of the impeller blade, which is not only beneficial to the cooling of the downstream guide vanes, but also beneficial to the sealing between the impeller blades and the guide vane blades, thus preventing the gas from "invading" the high-pressure turbine wheel cavity. Among them, the hollow structure is adopted inside the turbine blade edge plate, which is beneficial to reducing the weight of the impeller blades and improving the power-to-weight ratio of the engine.

[0076] In one embodiment of the present invention, a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array comprises:

[0077] Step 1: Determine the cooling structure of the turbine blade. Based on the blade shape obtained by the turbine aerodynamic design, the cooling structure design of the turbine blade is carried out. The cooling structure design such as air film cooling is not carried out for the blade edge plate for the time being, and a three-dimensional model of the blade with a cooling structure is obtained;

[0078] Step 2: Perform full three-dimensional heat-flow coupling calculation and analysis on the turbine blades. According to the inlet and outlet boundary conditions of the turbine blades, the constructed three-dimensional blade model is imported into the meshing program to divide the full three-dimensional calculation grid. Then, the full three-dimensional heat-flow coupling calculation and analysis program is used to carry out full three-dimensional heat-flow coupling calculation and analysis of the turbine blades, and the temperature distribution and data of the blade edge are obtained as a basis for subsequent analysis and comparison after using the spherical micro-tube array cooling design. The convective heat transfer coefficient of the turbine guide vane edge is obtained as the boundary condition for subsequent analysis, and the temperature distribution and data of the blade body are obtained.

[0079] If the temperature parameter of the turbine blade body meets the predetermined temperature standard, that is, the maximum temperature of the turbine blade body is lower than the temperature resistance grade of the metal material used, the next step is executed; if it does not meet the predetermined standard, the above steps are repeated until the temperature parameter of the turbine blade body reaches the predetermined standard;

[0080] Step 3: Determine the location where the turbine blade edge plate needs enhanced cooling. According to the temperature field distribution and data of the blade edge plate, determine the location of the high temperature area of ​​the blade edge plate, that is, the specific location where the turbine guide vane edge plate needs enhanced cooling. Subsequently, a micro-tube array cooling structure with spherical bulges will be arranged at these high temperature locations;

[0081] Step 4. Given the cooling parameters of the spherical bulge micro-tube array on the turbine moving blade edge plate. Based on the specific position of the moving blade edge plate that needs to be cooled determined in step 3, according to the structural characteristics of the moving blade edge plate surface that is approximately a parallelogram, combined with the structural dimension parameters of the moving blade edge plate such as thickness, width, and length, the cooling structural parameters of the transverse single-row spherical bulge micro-tube array are given: the position of the center line of the micro-spherical tube row set along the thickness direction of the edge plate (the distance H to the upper surface of the edge plate), the position of the center line of the micro-spherical tube row set along the width direction of the edge plate (the distance W to the side of the edge plate), the number n or distance Lk of the micro-spherical tube rows set along the width direction of the edge plate, the diameter of the micro-tube row (the through pipe diameter D and the spherical bulge diameter d q ), the path of each microtube arranged along the length direction of the edge plate.

[0082] Step 5: Construct a three-dimensional model of a turbine blade with a spherical bulge micro-tube array cooling structure on the edge plate. Based on the three-dimensional model of the blade with a cooling structure, using the given horizontal single-row spherical bulge micro-tube array cooling structure parameters, set spherical micro-tube rows and spherical bulges on the blade edge plate to construct a three-dimensional model of a turbine guide vane with a horizontal single-row spherical bulge micro-tube array cooling structure on the edge plate and a cooling structure on the blade body, and set a hollow micro-connecting pipe at the blade cavity position to connect the cooling channel front to back;

[0083] Step 6: Establish a three-dimensional heat-flow coupling calculation model for the cooling of the spherical bulge micro-tube array on the edge plate. Using the three-dimensional model of the turbine moving blade, ignoring the cooling structure of the moving blade body, only using the shape of the moving blade body, and only extracting the turbine moving blade edge plate model with a single-row spherical micro-tube array cooling structure on the edge plate;

[0084] Step 7: Full three-dimensional heat-flow coupling calculation and analysis of turbine blade edge plates. Import the constructed three-dimensional heat-flow coupling calculation model of spherical bulge micro-tube array cooling of turbine blade edge plates into the meshing program, divide the full three-dimensional calculation grid, and carry out full three-dimensional heat-flow coupling calculation and analysis of turbine blade edge plates based on the temperature and convection heat transfer coefficient of the turbine blade edge plates and blade body, as well as the temperature and pressure boundary conditions of the cooling air inlet and outlet, using the full three-dimensional heat-flow coupling calculation and analysis program, and obtain the temperature field distribution and data of the blade edge plates;

[0085] If the temperature parameters of the turbine moving blade edge plate meet the predetermined temperature standard (if the maximum temperature of the turbine moving blade edge plate is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine moving blade edge plate is lower than the temperature resistance grade of the metal material used; if the maximum temperature of the turbine moving blade edge plate is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine moving blade edge plate is reduced by not less than 10°C), then execute the next step; if it does not meet the predetermined standard, adjust the cooling structure parameters of the transverse single-row spherical bulge micro-tube array (reduce the distance from the center line to the flow surface of the edge plate, increase the number of micro-tube rows, increase the diameter of the micro-tubes, and increase the number of spherical bulges in each micro-tube row), and repeat steps 4 to 7 until the temperature parameters of the turbine moving blade edge plate meet the predetermined standard;

[0086] Step 8: Full three-dimensional heat-flow coupling calculation and analysis of the moving blade body and edge plate. Using the same turbine guide vane inlet and outlet boundary conditions as in step 2, the three-dimensional model of the turbine moving blade with the edge plate with spherical bulge micro-tube array cooling structure constructed in step 5 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 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 moving blade, and the temperature field distribution and data of the turbine moving blade (including the blade body and edge plate) after adding the spherical bulge micro-tube array cooling structure are obtained.

[0087] If the temperature parameter of the turbine blade (including the blade body and the edge plate) obtained in step eight meets the predetermined temperature standard, the next step is executed; if it does not meet the predetermined standard, steps one to eight are repeated until the temperature parameter of the turbine blade reaches the predetermined standard.

[0088] In another embodiment of the present invention, a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array is provided. The diameter of the cooling tube of the spherical bulge micro-tube array cooling structure is usually between 0.1 mm and 1 mm. The micro-tube array with a smaller diameter, in combination with the spherical bulge to strengthen the cooling structure, is conducive to doubling the heat exchange area of ​​the cooling channel and doubling the convective heat transfer coefficient, thereby achieving super cooling of the edge plate. Obviously, through the spherical bulge micro-tube array, not only can the full coverage of the high-pressure turbine blade edge plate cooling be achieved, but also the edge plate cooling requirements can be fully met. Therefore, the edge plate air film cooling can be cancelled. The problem that the air film is difficult to cover the cooling "dead zone" due to the influence of the lateral secondary flow in the end area and the limitation of the spatial structure of the traditional edge plate air film cooling will no longer exist, and the cooling and cooling requirements of the high-pressure turbine blade edge plate of the gas turbine can be more easily met.

[0089] In another embodiment of the present invention, a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array is provided. The turbine blade edge plate is cooled by a transverse single-row spherical bulge micro-tube array. The cooling air can be delivered to any position of the blade edge plate by reducing the diameter of the circular tubes of the micro-tube array (to a minimum of 0.1 mm), thereby achieving precise customized delivery of the edge plate cooling needs, and enhanced cooling through smaller-scale spherical pipes (to a minimum of 0.2 mm), so that the high-temperature area of ​​the edge plate can be cooled in a targeted manner.

[0090] In another embodiment of the present invention, a turbine blade edge plate is cooled by a transverse single-row spherical bulge micro-tube array, which eliminates the blade edge plate air film hole cooling structure, which is beneficial to weaken the impact of the blade edge plate air film cooling on the mainstream, reduce mixing losses, and improve turbine efficiency.

[0091] In another embodiment of the present invention, a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array is provided. The turbine blade edge plate is cooled by a single row of spherical bulge micro-tube arrays in a transverse direction, and the interior of the blade edge plate is a hollow structure, which can reduce the weight of the blade by 2%.

[0092] The present invention proposes a method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array, which is universal and not only limited to the design of high-pressure turbine blades of gas turbines, but also applicable to the design of high-pressure turbine blades of aircraft engines.

[0093] 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 turbine blade edge plate with a spherical bulge micro-tube array, characterized in that: The design method comprises: S101, determining the cooling structure of the turbine rotor blade body, performing full three-dimensional fluid-heat coupling calculation and analysis on the turbine rotor blade, obtaining the temperature distribution and data of the turbine rotor blade edge plate, and determining that the temperature parameters of the turbine rotor blade body meet the predetermined temperature standard; S102, determining the position of the high temperature area in the turbine blade edge plate where the spherical bulge micro-tube array cooling structure is to be arranged according to the temperature field distribution and data of the turbine blade edge plate; S103, according to the surface structure of the moving blade edge plate, combined with the structural dimension parameters of the moving blade edge plate including at least thickness, width, and length, a transverse single-row spherical bulge micro-tube array cooling structural parameter is given; S104, arranging a spherical micro-tube array and a spherical bulge on the rotor blade edge plate, and constructing a three-dimensional model of a turbine rotor blade with a cooling structure of a lateral single-row spherical bulge micro-tube array on the edge plate; S105, extracting a three-dimensional model of a turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure, and performing full three-dimensional fluid-thermal coupling calculation and analysis on the three-dimensional model of the turbine blade edge plate to obtain temperature field distribution and data of the turbine blade edge plate; S106, if the temperature parameter of the turbine blade edge plate meets the predetermined temperature standard, the next step is executed; otherwise, the cooling structure parameter of the transverse single-row spherical bulge micro-tube array is adjusted, and S103 to S105 are repeatedly executed until the temperature parameter of the turbine blade edge plate reaches the predetermined temperature standard; S107. Perform a full three-dimensional heat-flow coupling calculation and analysis on the turbine blade body and edge plate as a whole to obtain the temperature field distribution information of the turbine blade with a spherical bulge micro-tube array cooling structure on the edge plate. If the temperature parameter of the turbine blade meets the predetermined temperature standard, the design of the turbine blade edge plate cooling structure with a spherical bulge micro-tube array is completed; otherwise, repeat steps S101 to S107 until the temperature parameter of the turbine blade reaches the predetermined temperature standard.

2. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: Perform full three-dimensional fluid-heat coupling calculation and analysis on the turbine blades to obtain the temperature distribution and data of the turbine blade edge plate and determine the temperature distribution of the turbine blade body, including: Construct a three-dimensional model of turbine blades, divide the fluid domain and solid domain grids required for full three-dimensional calculations, perform full three-dimensional fluid-thermal coupling calculations and analysis of turbine blades, and obtain the temperature field distribution and data of turbine blade edge plates; Obtain the convection heat transfer coefficient h of the turbine blade edge plate flow surface r,yb and convection heat transfer As boundary conditions for subsequent analysis; If the temperature parameter of the turbine blade body meets the predetermined temperature standard, that is, the maximum temperature T of the turbine blade body Rblade,max Lower than the temperature resistance grade T of the metal material used R-M , T Rblade,max <T R-M , then execute S102; otherwise, re-determine the cooling structure of the turbine rotor blade body until the temperature parameter of the turbine rotor blade body reaches a predetermined standard.

3. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: The cooling structure parameters of the transverse single-row spherical bulge micro-tube array include: The position of the center line of the micro-spherical tubes arranged along the thickness direction of the moving blade edge plate, the position of the center line of the micro-spherical tubes arranged along the width direction of the moving blade edge plate, the number of micro-spherical tube rows arranged along the width direction of the moving blade edge plate, the tube diameter and length of each micro-tube row, and the path of each micro-tube arranged along the length direction of the moving blade edge plate; Among them, the position of the center line of the micro-spherical tube arranged along the thickness direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the upper surface of the edge plate; the position of the center line of the micro-spherical tube arranged along the width direction of the moving blade edge plate, that is, the distance from the center line of the micro-spherical tube to the side of the edge plate; the diameter of the micro-tube row includes the diameter of the through tube and the diameter of the spherical bulge.

4. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: The three-dimensional model of the turbine blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure is extracted, and the three-dimensional fluid-heat coupling calculation and analysis of the turbine blade edge plate three-dimensional model is performed to obtain the temperature field distribution and data of the turbine blade edge plate, including: Meshing is performed on the three-dimensional model of the turbine moving blade edge plate with a transverse single-row spherical bulge micro-tube array cooling structure of the edge plate, and the fluid domain and solid domain meshes required for full three-dimensional calculation are divided. Based on the temperature field distribution and data of the turbine moving blade edge plate, the Nusselt number of the turbine moving blade edge plate convective heat transfer, the convective heat transfer coefficient of the turbine moving blade edge plate, and the cooling air flow rate, the cooling air inlet and outlet temperature and pressure boundary conditions, a full three-dimensional fluid-heat coupling calculation and analysis of the turbine moving blade edge plate is performed to obtain the temperature field distribution and data of the moving blade edge plate; The Nusselt number is: The convective heat transfer coefficient is: The total mass flow rate of the microtube array is: Among them, Reynolds number Re=uD / ν, rotation number Ro=ΩD / u, density ratio DR=α v (T w -T c ), u is the fluid velocity at the microtube inlet, ν is the fluid kinematic viscosity coefficient, D is the straight tube diameter, Ω is the rotation speed, α v is the volume expansion coefficient, T w is the microtube wall temperature, L is the straight tube length, C1, C2, C3, C4 are flow heat transfer power indexes, n qg is the number of spherical bulges per microcapillary, d q is the diameter of the spherical bulge, m is the total mass flow rate of the microtube array, Q r,yb is the heat transferred from the gas to the edge plate, C p is the constant pressure specific heat capacity of the cold air, T g is the gas temperature on the edge plate side, h g is the convective heat transfer coefficient of the gas on the edge plate side, A is the heat transfer area on the gas side of the edge plate, T c is the cooling air inlet temperature of the microtube array, h c is the convective heat transfer coefficient of the cooling air, n is the number of microtubes, and λ is the thermal conductivity of the cooling air.

5. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: The temperature parameter of the turbine blade edge plate meets the predetermined temperature standard, including: If the maximum temperature of the turbine blade edge plate is higher than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used; if the maximum temperature of the turbine blade edge plate is lower than the temperature resistance grade of the metal material used, the predetermined temperature standard is: the maximum temperature of the turbine blade edge plate is reduced by no less than 10°C.

6. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: Adjusting the cooling structure parameters of the transverse single-row spherical bulge microtube array includes: The distance from the center line of the micro-spherical tube to the flow surface of the moving blade edge plate is reduced, the number of the micro-tube rows is increased, the diameter of the micro-tubes in the micro-tube rows is increased, and the number of spherical bulges in each micro-tube row is increased.

7. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: The diameter of the cooling circular tube section of the spherical bulge micro-tube array cooling structure is 0.1 mm to 1 mm, and the diameter of the spherical bulge is 1.5 to 2 times the diameter of the cooling circular tube section.

8. The method for designing a cooling structure of a turbine blade edge plate with a spherical bulge micro-tube array according to claim 1, characterized in that: The turbine blade edge plate is cooled by a transverse single-row spherical bulge micro-tube array, which reduces the diameter of the circular tubes of the micro-tube array and delivers cooling air to any position of the turbine blade edge plate, thereby achieving precise customized delivery of the turbine blade edge plate cooling requirements and targetedly cooling the high-temperature area of ​​the turbine blade edge plate.

9. The method for designing a cooling structure of a turbine blade edge plate 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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