A method and system for verifying the rupture speed of a roulette wheel

Abstract

The present invention discloses a method and a system for verifying the rupture speed of a turbine disk. The method includes performing a photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected; according to the rupture speed conversion formula, converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected made of the prototype material; comparing the rupture speed of the turbine disk to be detected made of the prototype material with the calculation result of the rupture speed in the conventional manner to verify whether the calculation result of the rupture speed in the conventional manner is accurate. The present invention uses the transition state of epoxy resin to simulate the elastic-plastic state of the prototype, and proposes a conversion formula for converting the rupture speed of the test model into that of the real test piece, laying the foundation for the engineering application of the model rupture test. The economic cost of the present invention is much lower than the cost of verifying by using a real turbine disk test piece for the rupture test, which is convenient for popularization and use.

Description

Technical Field

[0001] The present invention belongs to the technical field of engines, and particularly relates to a method and a system for verifying the rupture speed of a disk. Background Art

[0002] According to the research results published by the China Gas Turbine Establishment, during the normal acceleration process of an engine, abnormal conditions such as instantaneous overspeed, fuel regulator failure, afterburner malfunction, or shaft breakage and disconnection can cause the turbine disk to overspeed and even rupture. Once the turbine disk ruptures, the consequences are extremely serious. According to statistics, all ruptures of turbine disks and most rim ruptures are non-inclusive. After the fragments of the turbine disk penetrate the engine casing, they may cut off the fuel supply or control system, penetrate the fuel tank and cockpit, posing a serious threat to the crew and the aircraft. Therefore, an important design criterion for disks is to prevent rupture. To prevent the disk from rupturing before its normal service life, that is, premature failure, the conventional technical approach is to first calculate the rupture speed of the disk, and then verify it through the rupture test of a real disk test piece. Only when the finally obtained rupture speed of the disk is greater than the highest physical speed of the disk and has a certain margin can the design be considered successful. The rupture speed is obtained through finite element calculation, which is a very effective technical approach, but sometimes the error is relatively high.

[0003] Common methods for calculating the rupture speed include the mean stress method, small deformation analytical method, large deformation analytical method, and finite element method. These methods all have their own limitations, and whether their results are accurate requires verification through rupture tests or in actual use. In the aviation field, the commonly used verification method is to verify through the rupture test of a real disk, and the verification cost is quite high.

[0004] Therefore, the present invention proposes a method and a system for verifying the rupture speed of a disk to solve the above problems. Summary of the Invention

[0005] In view of the above problems, on the one hand, the present invention discloses a method for verifying the rupture speed of a disk, and the method specifically includes the following steps:

[0006] Perform a photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected;

[0007] According to the rupture speed conversion formula, convert the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material;

[0008] Compare the rupture speed of the turbine disk to be detected of the prototype material with the calculation result of the rupture speed by the conventional method to verify whether the calculation result of the rupture speed by the conventional method is accurate.

[0009] Further, the step of performing a photoelastic freezing fracture test on the turbine disk to be detected and obtaining the fracture speed of the turbine disk to be detected specifically includes:

[0010] According to the structure of the turbine disk to be detected, a primary design model is established according to a 1:1 size ratio;

[0011] Modify and equivalent process the design model to establish a secondary design model;

[0012] Make a model to be tested of epoxy resin material according to the secondary design model;

[0013] Preset temperature control conditions, and install and perform temperature control treatment on the model to be tested;

[0014] Perform a rotational fracture test on the model to be tested to obtain the fracture speed N of the turbine disk to be detected 模型断裂 。

[0015] Further, the step of performing a rotational test on the model to be tested specifically includes the following steps:

[0016] Perform a primary rotational fracture test on the model to be tested; wherein, the test speed is loaded steplessly until the model to be tested fractures;

[0017] When the model to be tested fractures, obtain the fracture speed N of the turbine disk to be detected 模型断裂 。

[0018] Further, the step that the test speed is loaded steplessly until the model to be tested fractures further includes:

[0019] Preset an expected fracture speed. When the test speed exceeds 20% of the expected fracture speed and still does not fracture, or fractures when it is lower than 80% of the expected fracture speed, stop the test;

[0020] Check whether there is an error in the steps of the primary rotational fracture test;

[0021] If there is an error, modify the incorrect steps of the primary rotational fracture test, re-perform the primary rotational fracture test and repeat the step of checking whether there is an error in the steps of the primary rotational fracture test;

[0022] If there is no error, perform a secondary rotational fracture test;

[0023] When the error between the fracture speed obtained from the secondary rotational fracture test and the fracture speed obtained from the primary rotational fracture test is within 8%, it is determined that the calculation result of the fracture speed by the conventional method is inaccurate;

[0024] Wherein, the value of the expected fracture speed is the calculation result of the fracture speed by the conventional method.

[0025] Further, before the step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected with the prototype material according to the rupture speed conversion formula, the following steps are also included:

[0026] Select a finalized turbine disk as the research object, and the finalized turbine disk and the turbine disk to be detected have the same prototype material;

[0027] Conduct tests on the research object to obtain relevant parameters of the calculation model;

[0028] And substitute the relevant parameters into the calculation model to obtain the correction coefficient X of the research object 修正系数 ; where

[0029] The calculation model is:

[0030]

[0031] The relevant parameters include the actual rupture speed of the finalized turbine disk made of the prototype material, the tensile load L when the finalized turbine disk made of the prototype material fractures 定型原型断裂 , the tensile load L when the finalized turbine disk made of the photoelastic material fractures 定型模型断裂 and the rupture speed N when the finalized turbine disk made of the photoelastic material fractures 定型模型断裂 ;

[0032] Further, the step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected with the prototype material according to the rupture speed conversion formula specifically includes:

[0033] Manufacture a tensile model, and the tensile model includes a prototype material tensile model and a photoelastic material tensile model;

[0034] Manufacture a rotation model, and the rotation model is a photoelastic model made of photoelastic material with the same prototype structure according to the similarity principle;

[0035] Conduct a tensile test on the tensile model to obtain the fracture loads of the prototype material tensile model and the photoelastic material tensile model respectively;

[0036] Conduct a rotation test on the photoelastic model to obtain the rupture speed when the photoelastic model fractures;

[0037] Calculate the rupture speed of the turbine disk to be detected according to the rupture speed conversion formula.

[0038] Further, the rupture speed conversion formula is:

[0039]

[0040] Where L 原型断裂is the tensile load at the fracture of the tensile model of the prototype material; L 模型断裂 is the tensile load at the fracture of the tensile model of the photoelastic material; N 模型断裂 is the rupture rotational speed at the fracture of the photoelastic model; N 原 is the rupture rotational speed of the turbine disk to be detected converted into the prototype material.

[0041] Furthermore, comparing the rupture rotational speed of the turbine disk to be detected with the calculation result of the rupture rotational speed in the conventional method to verify whether the calculation result of the rupture rotational speed in the conventional method is accurate specifically includes the following steps:

[0042] Calculate the rupture rotational speed N of the turbine disk to be detected according to the conventional method 待测实物 ;

[0043] Set the rupture rotational speed range according to the rupture rotational speed N 待测实物 ;

[0044] If N 原 exceeds the rupture rotational speed range, it is determined that the calculation result of the rupture rotational speed of the turbine disk to be detected obtained by the conventional method is inaccurate; otherwise, it is determined that the calculation result of the rupture rotational speed of the turbine disk to be detected obtained by the conventional method is accurate;

[0045] Among them, the rupture rotational speed range is (1±10%)N 待测实物 .

[0046] On the other hand, the present invention also discloses a verification system for the rupture rotational speed of a disk, and the system includes:

[0047] A photoelastic freezing rupture test device for performing a photoelastic freezing rupture test on the turbine disk to be detected to obtain the rupture rotational speed of the turbine disk to be detected;

[0048] A calculation center for obtaining the rupture rotational speed of the turbine disk to be detected and converting the rupture rotational speed of the turbine disk to be detected into the rupture rotational speed of the turbine disk to be detected of the prototype material according to the rupture rotational speed conversion formula;

[0049] A verification center for comparing the rupture rotational speed of the turbine disk to be detected of the prototype material with the calculation result of the rupture rotational speed in the conventional method to verify whether the calculation result of the rupture rotational speed in the conventional method is accurate.

[0050] Furthermore, the steps for the photoelastic freezing rupture test device to perform the photoelastic freezing rupture test on the turbine disk to be detected to obtain the rupture rotational speed of the turbine disk to be detected specifically include:

[0051] Establish a primary design model according to the structure of the turbine disk to be detected in a 1:1 size ratio;

[0052] Modify and perform equivalent processing on the design model to establish a secondary design model;

[0053] Fabricate a test model of epoxy resin material according to the secondary design model;

[0054] Preset temperature control conditions, install and perform temperature control processing on the test model;

[0055] Conduct a rotational fracture test on the test model to obtain the fracture speed N of the turbine disk to be detected 模型断裂 .

[0056] Furthermore, the verification center executes a comparison between the fracture speed of the turbine disk to be detected and the calculation result of the fracture speed in the conventional method to verify whether the calculation result of the fracture speed in the conventional method is accurate. Specifically, it includes the following steps:

[0057] Calculate the fracture speed N of the turbine disk to be detected according to the conventional method 待测实物 ;

[0058] Set a fracture speed range according to the fracture speed N 待测实物 ;

[0059] If N 原 exceeds the fracture speed range, it is determined that the calculation result of the fracture speed of the turbine disk to be detected obtained by the conventional method is inaccurate; otherwise, it is determined that the calculation result of the fracture speed of the turbine disk to be detected obtained by the conventional method is accurate;

[0060] Among them, the fracture speed range is (1 ± 10%)N 待测实物 .

[0061] The present invention realizes a principled breakthrough in the method for verifying the fracture speed of a disk. Through the photoelastic fracture test of an epoxy resin model, it is converted into the fracture speed of the turbine disk to be detected made of the prototype material through a formula to verify whether the calculation result of the fracture speed of the disk test piece is correct. Using a turbine disk of a mature model to obtain a correction coefficient with small error, it is easy to implement, the conversion formula is simple, and it is easy to master. The present invention utilizes the successful experience of existing technologies and still utilizes geometric similarity, boundary condition similarity, and load similarity. However, compared with existing technologies, it has two breakthroughs. One is to use the transition state of epoxy resin to simulate the elastoplastic state of the prototype, and the other is to introduce a correction coefficient. It lays the conditions for the model fracture test to enter engineering applications. The economic cost of the present invention is much lower than the cost of using a real disk test piece for fracture test verification. It is convenient for popularization and use.

[0062] Other features and advantages of the present invention will be described in the subsequent specification, and part of them will be obvious from the specification or understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained through the structures pointed out in the specification, claims, and drawings. Brief Description of the Drawings

[0063] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0064] Figure 1 Shows a schematic diagram of the verification process of the rupture speed of a wheel disc according to an embodiment of the present invention. Detailed Embodiments

[0065] In order to make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0066] The present invention discloses a method for verifying the rupture speed of a wheel disc. Before verifying the rupture speed of the wheel disc, the following steps are included: selecting a finalized turbine disc as the research object, and the finalized turbine disc has the same prototype material as the turbine disc to be detected; conducting tests on the research object to obtain relevant parameters of the calculation model; and substituting the relevant parameters into the calculation model to obtain the correction coefficient X of the research object 修正系数 ; wherein,

[0067] The calculation model is:

[0068]

[0069] The relevant parameters include the actual rupture speed of the finalized turbine disc made of the prototype material, the tensile load L when the finalized turbine disc made of the prototype material fractures 定型原型断裂 , the tensile load L when the finalized turbine disc made of the photoelastic material fractures 定型模型断裂 and the rupture speed N when the finalized turbine disc made of the photoelastic material fractures 定型模型断裂 .

[0070] In an embodiment of the present invention, the method for verifying the rupture speed of the wheel disc includes the following specific steps:

[0071] (1) Conduct a photoelastic freezing rupture test on the turbine disc to be detected to obtain the rupture speed of the turbine disc to be detected;

[0072] (1.1) Establish a primary design model according to the structure of the turbine disk to be detected, in a 1:1 size ratio.

[0073] (1.2) Modify and perform equivalent processing on the design model to establish a secondary design model.

[0074] (1.3) Fabricate a test model made of epoxy resin material based on the secondary design model.

[0075] (1.4) Preset temperature control conditions, and install and perform temperature control on the test model.

[0076] (1.5) Conduct a rotational fracture test on the test model to obtain the fracture speed N of the turbine disk to be detected. 模型断裂 ;

[0077] Specifically, it includes:

[0078] (1.5.1) Conduct a rotational test on the test model through a centrifugal load testing machine; that is, conduct a single rotational fracture test on the test model. Among them, the test speed is loaded steplessly until the test model fractures.

[0079] Specifically, it also includes:

[0080] Preset the expected fracture speed. When the test speed exceeds 20% of the expected fracture speed and still does not fracture, or fractures when it is lower than 80% of the expected fracture speed, abort the test.

[0081] Check whether there are errors in the steps of the single rotational fracture test.

[0082] If there are errors, modify the incorrect steps of the single rotational fracture test, conduct a new single rotational fracture test, and repeat the step of checking whether there are errors in the steps of the single rotational fracture test.

[0083] If there are no errors, conduct a secondary rotational fracture test.

[0084] When the error between the fracture speed obtained from the secondary rotational fracture test and the fracture speed obtained from the single rotational fracture test is within 8%, it is determined that the calculation result of the fracture speed by the conventional method is inaccurate; it is necessary to improve the calculation method to carry out other applications.

[0085] Among them, the value of the expected fracture speed is the calculation result of the fracture speed by the conventional method.

[0086] (1.5.2) When the test model fractures, obtain the fracture speed N of the turbine disk to be detected. 模型断裂 .

[0087] It should be noted that in this embodiment, since the errors of the primary rotation rupture test or the secondary rotation rupture test are small, that is, the repeatability of the rupture rotation speeds obtained from the two rotation rupture tests is good, the rupture rotation speed N of the turbine disk to be detected obtained in step 1.5.2 模型断裂 can be the rupture rotation speed obtained from the primary rotation rupture test or the secondary rotation rupture test.

[0088] (2) According to the rupture rotation speed conversion formula, convert the rupture rotation speed of the turbine disk to be detected into the rupture rotation speed of the turbine disk to be detected of the prototype material;

[0089] Specifically, it includes:

[0090] Fabricate a tensile model, and the tensile model includes a prototype material tensile model and a photoelastic material tensile model;

[0091] Fabricate a rotation model, and the rotation model is a photoelastic model with the same structure as the prototype fabricated from the photoelastic material according to the similarity principle;

[0092] Conduct a tensile test on the tensile model to obtain the fracture loads of the prototype material tensile model and the photoelastic material tensile model respectively;

[0093] Conduct a rotation test on the photoelastic model to obtain the rupture rotation speed when the photoelastic model fractures;

[0094] Calculate the rupture rotation speed of the turbine disk to be detected according to the rupture rotation speed conversion formula.

[0095] (3) Compare the rupture rotation speed of the turbine disk to be detected of the prototype material with the calculation result of the rupture rotation speed by the conventional method to verify whether the calculation result of the rupture rotation speed by the conventional method is accurate;

[0096] (3.1) Calculate the rupture rotation speed N of the turbine disk to be detected according to the conventional method 待测实物 ;

[0097] (3.2) Set a rupture rotation speed range according to the rupture rotation speed N 待测实物 , and the rupture rotation speed range is (1±10%)N 待测实物 ;

[0098] (3.3) If N 原 exceeds the rupture rotation speed range, it is determined that the calculation result of the rupture rotation speed of the turbine disk to be detected obtained by the conventional method is inaccurate; otherwise, it is determined that the calculation result of the rupture rotation speed of the turbine disk to be detected obtained by the conventional method is accurate.

[0099] In an embodiment of the present invention, in step (1), the photoelastic freeze rupture test of the turbine disk (newly designed turbine disk and not yet detected) includes the design and fabrication of the model, the installation of the model in temperature control and the rupture test. Among them,

[0100] The model is designed according to the epoxy resin model: real test piece = 1:1 size for the preliminary design of the first design model; the preliminary designed model is modified. The modification principle is to pre-confirm the parts with complex machining, easy to have notches or fractures, and then according to the equivalent principle, equivalent treatment is carried out on most parts with complex machining, easy to have notches or fractures. After the equivalent treatment, it is easy to machine without affecting the stress analysis of the parts concerned in the design. The structure of the parts concerned in the design is retained to be the same as the prototype to obtain the second design model. The manufacturing method of the epoxy resin model is as follows: use a vacuum casting molding machine and the vacuum casting process of the photoelastic model to cast the blank. When casting, use the photoelastic model blank mold, and make the model for the test by CNC milling or other machining methods.

[0101] The installation and temperature control of the model include: install the machined epoxy resin model on the model hybrid loading device; carry out temperature control on the model. The temperature control curve is to rise from room temperature to 80 °C in 1 h, then rise at a rate of 5 °C / h to 110 °C, keep warm for 24 h and then rise at a rate of 5 °C / h to the preset temperature. The preset temperature is (110 - 140) °C, and the preset temperature must ensure that it is within the transition section range of the epoxy resin model material. After the temperature control reaches the preset temperature, keep warm, and the holding time is 5 h - 15 h.

[0102] After keeping warm for 1 h - 5 h (the specific holding time is determined according to the volume of the experimental model), start the drive motor and slowly increase the speed. During the process of increasing the speed, closely monitor the change of the vibration value and abnormal sound. If there is abnormal sound or the vibration value exceeds the limit value during the test, stop the vehicle for inspection. When the test speed is increased to the expected rupture speed (the expected rupture speed is the value of the turbine disk rupture speed calculated by the conventional method), if the vibration value increases sharply or the rupture sound is heard, the test stops; if the rupture sound is not heard or the change of the vibration value is not significant, continue to increase the speed until the speed exceeds the expected rupture speed by 20%. If it still does not rupture when exceeding the expected rupture speed by 20% or ruptures when lower than 80% of the expected rupture speed, the test must be aborted, find out the specific reason, and after putting forward a feasible implementation plan, then carry out the next step of work. After multiple tests, when the numerical values of the multiple test results are close, the test results shall prevail.

[0103] As an embodiment of the present invention, during the installation and temperature control of the model, the predetermined temperature is 120°C and the heat preservation time is 10 h. After heat preservation for 2 h, start the drive motor and then slowly increase the speed. During the process of increasing the speed, closely monitor the change of the vibration value and abnormal sound. If there is an abnormal sound or the vibration value exceeds the limit value during the test, stop the vehicle for inspection. The test speed is increased to 3,500 revolutions per minute. After the speed reaches 3,500 revolutions per minute, the tester should closely monitor the change of the monitored vibration value. Stop the vehicle when hearing a cracking sound or the vibration value exceeds 0.6 g. The corresponding test speed is the cracking speed of the turbine disk model obtained by the test. After the equipment cools naturally to room temperature, stop the vehicle for inspection. If it is found that the model does not crack during the stop inspection, the specific reason must be found, and after proposing a feasible implementation plan, retest.

[0104] It is necessary to note that during temperature control and heat preservation, it must be ensured that the model is in the transition state. When the composition of the model is different, the transition state temperature of the model is different. For each material, its material thermo-optical curve needs to be obtained by the photoelastic freezing cracking test. The temperature control and heat preservation temperature can first take the intermediate temperature of the transition curve and be appropriately adjusted according to the test deformation results. Select the corresponding temperature of the model with the smallest deformation error between the model cracking and the physical cracking as the predetermined temperature for temperature control and heat preservation.

[0105] In addition, the conversion formula for the cracking speed in step (2) is:

[0106]

[0107] where L 原型断裂 is the tensile load when the tensile model of the prototype material fractures; L 模型断裂 is the tensile load when the tensile model of the photoelastic material fractures; N 模型断裂 is the cracking speed when the photoelastic model fractures; N 原 is the cracking speed of the turbine disk to be detected converted into the prototype material;

[0108] In step (2), during the production process of the tensile model and the rotating model, select a representative part from the whole tensile model for design, select the part concerned by the design as the core part, and use the equivalent principle to equivalently replace other parts. When manufacturing the model, process it as a whole with the loading body; select a representative part from the whole rotating model for design, select the part concerned by the design as the core part, and cooperate other parts with the transition section of the existing centrifugal rotating system;

[0109] The processing process is based on the patent method of a photoelastic model and its manufacturing method with the existing authorized publication number: CN106393527B. The processing of key parts uses the same processing equipment as the prototype to ensure that the accuracy is the same as that of the prototype.

[0110] In an embodiment of the present invention, in the process of conducting a tensile test on a tensile model, a tensile test is performed on a photoelastic material tensile model under temperature control conditions. During loading, stepless loading is carried out until the local model fractures. This experiment is based on the model hybrid loading device in the existing authorized publication number CN103968979B; under normal temperature conditions, a tensile test is performed on a prototype material tensile model. During loading, stepless loading is carried out until the local model fractures. This experiment is conducted on a material testing machine.

[0111] In the process of conducting a rotation test on a rotation model, a photoelastic freezing fracture test in a rotating state is performed on a photoelastic model under temperature control conditions. During loading, the rotation speed is slowly increased until the local model fractures. This experiment is based on the model hybrid loading device in the existing authorized publication number CN103968979B; under normal temperature conditions, a physical experiment in a rotating state is performed on a shaped turbine disk made of prototype material. During loading, the rotation speed is increased in accordance with the specifications of the physical experiment until the prototype rotation model fractures. This test is conducted on a centrifugal load testing machine.

[0112] Among them, introducing a correction coefficient into the fracture rotation speed conversion formula can improve the accuracy of the photoelastic freezing fracture test results. After the correction coefficient of the same material is obtained, it can be reused repeatedly without the need to obtain it through re-experimentation. Specifically, in the process of obtaining the correction coefficient, a turbine disk made of the same raw material as the turbine disk to be detected and already shaped can be selected for the test, or a turbine disk that has been physically verified (the structure of the turbine disk is already shaped, that is, a turbine disk that does not require structural modification according to the design criteria) can be selected for the test.

[0113] During the photoelastic freezing fracture test, the design process of the model should be coordinated with the loading system of the existing centrifugal load testing machine as much as possible, which can save funds and effectively shorten the test cycle.

[0114] When manufacturing the photoelastic model, it is processed using the patent method based on the existing authorized publication number: CN106393527B, a photoelastic model and its manufacturing method. The processing of key parts adopts the same processing equipment as the prototype to ensure that its accuracy is the same as that of the prototype. The photoelastic model blank mold based on the existing authorized publication number CN104476708B is used, and an epoxy resin model blank is manufactured using a vacuum casting molding machine based on the existing publication number CN201501072U or publication number CN205021886U and the vacuum casting process method of the photoelastic model based on the existing authorized publication number CN102642263B. The epoxy resin model blank is machined using equipment such as saws, lathes, milling machines, broaching machines, and grinders to machine a local model that meets the requirements of the design drawings. The replacement tensile model and replacement rotation model for the test adopt the same processing method and equipment as when machining the entire prototype.

[0115] After obtaining the correction factor of the same prototype material, it can be directly adopted when conducting other tests without repetition. When verifying the rupture speed of the turbine disk made of the same prototype material for the second time, the steps of obtaining the correction factor can be omitted (even if the structure of the turbine disk has changed, the previously obtained correction factor can still be directly adopted). After introducing the correction factor, the model rupture test meets the conditions for engineering application.

[0116] During the actual experiment, the preset rupture speed range in step (3.2) is (1 ± 10%)N 待测实物 , that is, when the rupture speed N 原 of the turbine disk to be tested of the prototype material obtained through the rupture speed conversion formula and the rupture speed N 待测实物 of the turbine disk to be tested obtained through the conventional method have an error not exceeding 10%, it is determined that the calculation result of the rupture speed by the conventional method is accurate. At the same time, to improve the safety of the turbine disk, take the smaller value of N 原 and N 待测实物 as the rupture speed of the turbine disk of the prototype material.

[0117] On the other hand, the present invention also proposes a verification system for the rupture speed of a disk, and the system includes:

[0118] A photoelastic freeze rupture test device for conducting a photoelastic freeze rupture test on the turbine disk to be tested to obtain the rupture speed of the turbine disk to be tested;

[0119] A calculation center for obtaining the rupture speed of the turbine disk to be tested and converting the rupture speed of the turbine disk to be tested into the rupture speed of the turbine disk to be tested of the prototype material according to the rupture speed conversion formula;

[0120] A verification center for comparing the rupture speed of the turbine disk to be tested of the prototype material with the calculation result of the rupture speed by the conventional method to verify whether the calculation result of the rupture speed by the conventional method is accurate.

[0121] The system further includes:

[0122] A model hybrid loading device for conducting a tensile test on the tensile model under temperature control conditions and obtaining the fracture load of the tensile model; conducting a photoelastic freeze rupture test on the rotating state of the rotating model and obtaining the rupture speed of the rotating model;

[0123] A centrifugal load testing machine for conducting a rotating state physical test on the rotating model at normal temperature and obtaining the rupture speed of the rotating model;

[0124] A material testing machine for conducting a tensile test on the tensile model at normal temperature and obtaining the fracture load of the tensile model;

[0125] The present invention has achieved a principled breakthrough in the method for verifying the rupture speed of a roulette wheel. In the prior art, photoelastic freeze rupture tests all follow the similarity principle, using the photoelastic state of epoxy resin to simulate the linear elastic state of the prototype. However, the present invention uses the transition state of epoxy resin to simulate the elastoplastic state of the prototype, thus creating conditions for simulating the fracture state of the prototype. Obtaining a correction coefficient with a small error using a mature model of the turbine disk is convenient to implement, the conversion formula is simple, and it is easy to master. The present invention utilizes the successful experience of the existing technology and still uses geometric similarity, boundary condition similarity, and load similarity. However, compared with the existing technology, it has two breakthroughs. One is using the transition state of epoxy resin to simulate the elastoplastic state of the prototype, and the other is introducing a correction coefficient. It lays the foundation for the model rupture test to enter engineering applications. The economic cost of the present invention is much lower than the cost of using a real roulette wheel test piece for rupture test verification. It is convenient for popularization and use.

[0126] Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for verifying the rupture speed of a turbine disk, characterized in that, the method specifically includes the following steps: Conduct a photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected; According to the rupture speed conversion formula, convert the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material; Compare the rupture speed of the turbine disk to be detected of the prototype material with the calculation result of the rupture speed in the conventional method to verify whether the calculation result of the rupture speed in the conventional method is accurate; Before the step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material according to the rupture speed conversion formula, the following steps are also included: Select a finalized turbine disk as the research object, and the finalized turbine disk has the same prototype material as the turbine disk to be detected; Conduct tests on the research object to obtain relevant parameters of the calculation model; And substitute the relevant parameters into the calculation model to obtain the correction coefficient X of the research object 修正系数 ; where The calculation model is: The relevant parameters include the actual fracture speed of the shaped turbine disk made of the prototype material, and the tensile load L when the shaped turbine disk made of the prototype material fractures 定型原型断裂 , the tensile load L when the shaped turbine disk made of the photoelastic material fractures 定型模型断裂 , and the fracture speed N when the shaped turbine disk made of the photoelastic material fractures 定型模型断裂 ; The step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material according to the rupture speed conversion formula specifically includes: Manufacture a tensile model, and the tensile model includes a prototype material tensile model and a photoelastic material tensile model; Manufacture a rotation model, and the rotation model is a photoelastic model made of photoelastic material according to the similarity principle and having the same prototype structure as the turbine disk to be detected; Conduct a tensile test on the tensile model to obtain the fracture loads of the prototype material tensile model and the photoelastic material tensile model respectively; Conduct a rotation test on the photoelastic model to obtain the rupture speed when the photoelastic model fractures; Calculate the rupture speed of the turbine disk to be detected according to the rupture speed conversion formula; The rupture speed conversion formula is: Among them, L 原型断裂 is the tensile load at the fracture of the tensile model of the prototype material; L 模型断裂 is the tensile load at the fracture of the tensile model of the photoelastic material; N 模型断裂 is the rupture rotational speed at the fracture of the photoelastic model; N 原 is the rupture rotational speed of the turbine disk to be detected converted into the prototype material.

2. The verification method according to claim 1, characterized in that, the step of conducting a photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected specifically includes: Establish a primary design model according to the structure of the turbine disk to be detected at a 1:1 size ratio; Modify and equivalent process the design model to establish a secondary design model; Manufacture a test model of epoxy resin material according to the secondary design model; Preset temperature control conditions and conduct installation and temperature control treatment on the test model; Perform a rotational rupture test on the model to be tested to obtain the rupture speed N of the turbine disk to be detected 模型断 rupture 3. The verification method according to claim 2, characterized in that, the rotation rupture test on the test model specifically includes the following steps: Conduct a primary rotation rupture test on the test model; wherein, the test speed is loaded steplessly until the test model ruptures; When the model to be tested ruptures, obtain the rupture speed N of the turbine disk to be detected 模型断裂 .

4. The verification method according to claim 3, characterized in that, the test speed is loaded steplessly until the test model ruptures further includes: Preset the expected rupture speed. When the test speed exceeds 20% of the expected rupture speed and still does not rupture or ruptures when it is lower than 80% of the expected rupture speed, stop the test; Check whether there is an error in the steps of the primary rotation rupture test; If there is an error, modify the incorrect steps of the primary rotation rupture test, conduct a new primary rotation rupture test and repeat the step of checking whether there is an error in the steps of the primary rotation rupture test; If there is no error, conduct a secondary rotation rupture test; When the error between the rupture speed obtained from the secondary rotational rupture test and the rupture speed obtained from the primary rotational rupture test is within 8%, it is determined that the calculation result of the rupture speed by the conventional method is inaccurate; Among them, the value of the predicted rupture speed is the calculation result of the rupture speed by the conventional method.

5. The verification method according to claim 1, characterized in that the comparison of the rupture speed of the turbine disk to be detected with the calculation result of the rupture speed by the conventional method to verify whether the calculation result of the rupture speed by the conventional method is accurate specifically includes the following steps: Calculate the rupture speed N of the turbine disk to be detected according to the conventional method 待测实物 ; According to the rupture speed N 待测实物 Set the rupture speed range; If N 原 exceeds the rupture speed range, it is determined that the calculated result of the rupture speed of the turbine disk to be detected obtained by the conventional method is inaccurate; Otherwise, it is determined that the calculation result of the rupture speed of the turbine disk to be detected obtained by the conventional method is accurate; Among them, the rupture speed range is (1 ± 10%)N 待测实物 .

6. A verification system for the rupture speed of a disk, characterized in that the system includes: a photoelastic freeze rupture test device for performing a photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected; a calculation center for obtaining the rupture speed of the turbine disk to be detected and converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material according to the rupture speed conversion formula; a verification center for comparing the rupture speed of the turbine disk to be detected of the prototype material with the calculation result of the rupture speed by the conventional method to verify whether the calculation result of the rupture speed by the conventional method is accurate; Before the step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material according to the rupture speed conversion formula, the following steps are further included: Select a finalized turbine disk as the research object, and the finalized turbine disk has the same prototype material as the turbine disk to be detected; Perform tests on the research object to obtain relevant parameters of the calculation model; And substitute the relevant parameters into the calculation model to obtain the correction coefficient X of the research object 修正系数 ; where The calculation model is: The relevant parameters include the actual rupture speed of the finalized turbine disk made of the prototype material, and the tensile load L at the time of fracture of the finalized turbine disk made of the prototype material 定型原型断裂 , the tensile load L at the time of fracture of the finalized turbine disk made of the photoelastic material 定型模型断裂 , and the rupture speed N at the time of fracture of the finalized turbine disk made of the photoelastic material 定型模型断裂 ; The step of converting the rupture speed of the turbine disk to be detected into the rupture speed of the turbine disk to be detected of the prototype material according to the rupture speed conversion formula specifically includes: Manufacture a tensile model, and the tensile model includes a prototype material tensile model and a photoelastic material tensile model; Manufacture a rotational model, and the rotational model is a photoelastic model made of photoelastic material according to the similarity principle and having the same prototype structure as the turbine disk to be detected; Perform a tensile test on the tensile model to obtain the fracture loads of the prototype material tensile model and the photoelastic material tensile model respectively; Perform a rotational test on the photoelastic model to obtain the rupture speed at which the photoelastic model fractures; Calculate the rupture speed of the turbine disk to be detected according to the rupture speed conversion formula; The rupture speed conversion formula is: Among them, L 原型断裂 is the tensile load at the fracture of the tensile model of the prototype material; L 模型断裂 is the tensile load at the fracture of the tensile model of the photoelastic material; N 模型断裂 is the rupture rotational speed at the fracture of the photoelastic model; N 原 is the rupture rotational speed of the turbine disk to be detected converted into the prototype material.

7. The verification system for the rupture speed of a disk according to claim 6, characterized in that the step of the photoelastic freeze rupture test device performing the photoelastic freeze rupture test on the turbine disk to be detected to obtain the rupture speed of the turbine disk to be detected specifically includes: Establish a primary design model according to the structure of the turbine disk to be detected at a 1:1 dimensional ratio; Modify and equivalently process the design model to establish a secondary design model; Manufacture an epoxy resin material test model according to the secondary design model; Preset temperature control conditions and perform installation and temperature control processing on the test model; Perform a rotational rupture test on the model to be tested to obtain the rupture speed N of the turbine disk to be detected 模型断 rupture 8. The verification system for the rupture speed of a disk according to claim 6, characterized in that The verification center performs a comparison between the rupture speed of the turbine disk to be detected and the calculation result of the rupture speed in the conventional method, and verifies whether the calculation result of the rupture speed in the conventional method is accurate. The specific steps are as follows: Calculate the rupture speed N of the turbine disk to be detected according to the conventional method 待测实物 ; According to the rupture speed N 待测实物 Set the rupture speed range; If N 原 exceeds the rupture speed range, it is determined that the calculated result of the rupture speed of the turbine disk to be detected obtained by the conventional method is inaccurate; Otherwise, it is determined that the calculation result of the rupture speed of the turbine disk to be detected obtained by the conventional method is accurate; Among them, the rupture speed range is (1 ± 10%)N 待测实物 .

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