High-temperature and high-cycle fatigue test device and method for aero-engine turbine blade simulation part

Abstract

The invention provides a high-temperature and high-cycle fatigue test device and method for an aero-engine turbine blade simulation part. The test device comprises a vibration test bench, a water cooling disc, a tool clamp base, a tool clamp cover plate, a test rack assembly, a laser displacement sensor, an acceleration sensor, a high-temperature furnace heating system, a temperature sensor, a data acquisition and modal analysis device, a vibration control and data analysis system, a vibration control device and a vibration test bench water cooler. The water cooling disc is fixed on the vibration test bench, the tool clamp base is fixed on the water cooling disc, and the laser displacement sensor is installed on the test rack assembly; the acceleration sensor is fixed on the vibration test bed or the water cooling disc, and the high-temperature furnace heating system is fixed on the water cooling disc; a probe of the temperature sensor is placed around the simulation piece for temperature measurement; the data acquisition and modal analysis device, the vibration control and data analysis system, the vibration control device and the vibration test bench are connected through communication cables.

Description

Technical Field

[0001] The present invention relates to the technical field of aero-engines, and in particular to a high-temperature high-cycle fatigue test device and a test method for a simulated turbine blade of an aero-engine. Background Art

[0002] Aircraft engines are highly complex and sophisticated thermal machines, and turbine blades are important components. To improve the performance of aircraft engines, it is necessary to improve the performance of turbine blades. Since turbine blades often work in high temperature, high pressure, and high speed environments, they are prone to generate large vibration stress and high cycle fatigue failure under the action of airflow excitation.

[0003] Therefore, how to study the high-cycle fatigue characteristics of turbine blades, reveal their damage mechanism, and propose methods to improve the life of turbine blades is one of the urgent problems to be solved.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present invention, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the embodiments of the present invention is to provide a high temperature and high cycle fatigue test device and test method for a simulated aircraft engine turbine blade.

[0006] Other features and advantages of the present invention will become apparent from the following detailed description, or may be learned in part by practice of the present invention.

[0007] According to one aspect of an embodiment of the present invention, a high-temperature and high-cycle fatigue test device for a simulated aircraft engine turbine blade is provided, and the fatigue test device includes: a vibration test bench, a water-cooling plate, a fixture base, a fixture cover, a test frame assembly, a laser displacement sensor, an acceleration sensor, a high-temperature furnace heating system, a temperature sensor, a data acquisition and modal analysis device, a vibration control and data analysis system, a vibration control device, and a vibration test bench water cooler; wherein, the water-cooling plate is fixed on the vibration test bench, and the vibration test bench water cooler forms a water cooling cycle with the water-cooling plate through a water inlet pipe and a water outlet pipe; the fixture base is fixed on the water-cooling plate, and the fixture base cooperates with the fixture cover to realize The simulation part is fixed; the test frame assembly is arranged corresponding to the work fixture base, and the laser displacement sensor is adjustably mounted on the test frame assembly; the acceleration sensor is fixed on the vibration test bench or the water cooling plate to sense acceleration; the high-temperature furnace heating system is fixed on the water cooling plate, and the heating plate of the high-temperature furnace heating system covers around the fixture base and the fixture cover to heat the simulation part; the probe of the temperature sensor is placed around the simulation part through the observation window glass plate of the high-temperature furnace heating system to measure the temperature; the data acquisition and modal analysis equipment, the vibration control and data analysis system, the vibration control equipment and the vibration test bench are connected by communication cables.

[0008] In an exemplary embodiment of the present disclosure, the test frame assembly includes a vertical support assembly and a horizontal mounting rod structure, and holes that match the groove holes on the surface of the vertical support assembly are arranged on both sides of the horizontal mounting rod, and the vertical support assembly and the horizontal mounting rod are connected by bolts; the horizontal mounting rod is provided with a groove that enables the laser displacement sensor to move.

[0009] In an exemplary embodiment of the present disclosure, a groove is provided in each of the assembly surfaces of the fixture base and the fixture cover for matching and fixing the simulation part.

[0010] In an exemplary embodiment of the present disclosure, the test device further comprises a base, and the test frame assembly and the vibration test table are both fixed on the base.

[0011] In an exemplary embodiment of the present disclosure, the data acquisition and modal analysis device has eight channels, each channel has a maximum sampling rate of 204.8 kHz and has an independent LED status display light.

[0012] In an exemplary embodiment of the present disclosure, the acceleration sensor has a range of 500g, a sensitivity of 10.42mV / g, and a resolution of 0.0015g.

[0013] In an exemplary embodiment of the present disclosure, the linear range of the laser displacement sensor is 50 mm, the sampling frequency range is 1.5 KHz to 49 KHz, and the resolution is 7.5 um.

[0014] In an exemplary embodiment of the present disclosure, the rated sinusoidal excitation force of the vibration test bench is 10KN, and the maximum acceleration is 1000m / s 2 , rated displacement is 51mm.

[0015] According to another aspect of an embodiment of the present invention, a high temperature and high cycle fatigue test method for a simulated aircraft engine turbine blade is provided. The fatigue test method comprises:

[0016] Providing the above fatigue testing device;

[0017] Conducting an air tightness test on the water cooling plate of the fatigue test device to ensure that the cooling capacity and air tightness of the water cooling plate meet the preset conditions;

[0018] Turn on the vibration control device and start the fatigue test device; perform the test by the force hammer excitation method, and the mobile force hammer method adopts the method of multi-point excitation and single-point measurement; before the test, it is necessary to complete the establishment of the geometric model in the modal analysis software based on the geometric shape of the simulation part; paste the acceleration sensor to an excitation point of the simulation part, and knock the corresponding excitation point according to the instruction in the modal analysis software, and the acceleration sensor can obtain the acceleration response of the point. After the signal acquisition of all points is completed, the modal parameters of the simulation part are identified by the modal analysis system;

[0019] The stress at the maximum stress position of the simulated part is calibrated by combining the finite element analysis results with the strain measurement results of the simulated part, and the stress at high temperature is calibrated by the indirect method;

[0020] A frequency sweep test is performed on the installed and fixed simulation part at room temperature, and the natural frequency of the simulation part is recorded; then the heating program of the high-temperature furnace heating controller is set to heat the simulation part. When the temperature of the simulation part reaches the target temperature, it is kept warm for ten minutes and a high-temperature frequency sweep test is performed to record the first-order natural frequency of the simulation part; finally, a high-cycle fatigue test is performed by tracking and dwelling to control the amplitude during the test;

[0021] The test termination conditions are set to be the natural frequency of the simulated part dropping by 2% or the appearance of obvious cracks on the surface of the simulated part; or, the test cycle number reaches 10. 7 The test was terminated.

[0022] In an exemplary embodiment of the present disclosure, the vibration stress calibration test includes:

[0023] Determine the location of the strain measurement point and select the location with greater stress near the clamping end of the simulation part to paste the strain gauge;

[0024] The vibration test bench is used to perform a resonance dwell test on the simulation component at a target order, the vibration response of the simulation component in a first-order resonance state is measured, the strain amplitude at different amplitudes is recorded, and a relationship curve between the two is obtained by linear fitting;

[0025] The determination of the proportionality coefficient K is based on the results of finite element analysis. It is necessary to perform finite element harmonic response analysis on the simulation component, the fixture as a whole, and the model. Given the overall displacement amplitude, the stress cloud diagram of the simulation component as a whole and the test section is obtained; the stress of all nodes in the area corresponding to the strain gauge pasting position is extracted, and the average stress value in the area is calculated. The stress value is the stress value at the strain gauge measuring point and the maximum stress value of the simulation component. The proportionality coefficient K can be obtained by dividing the latter stress value by the former stress value;

[0026] The relationship between the end displacement of the simulated component and the strain at the measuring point measured at room temperature is used to approximately replace the relationship between the end displacement of the simulated component and the strain at the measuring point under high temperature; the strain value is multiplied by the elastic modulus at the corresponding temperature to obtain the stress value at the corresponding temperature, and the stress value at the corresponding temperature is multiplied by the proportional coefficient K to obtain the maximum stress of the simulated component at high temperature. This maximum stress value is the stress level of the high cycle fatigue test.

[0027] The present invention provides a high-temperature, high-cycle fatigue test device for a simulated aircraft engine turbine blade. Compared with the traditional fatigue test method using electromagnetic induction heating, the test device provided by the present invention has low construction cost, is easy to maintain, flexible to install, and is easy to operate. It does not require large-scale infrastructure construction and a large number of personnel to conduct test tracking, thereby reducing labor costs. The test device provided by the present invention can be applied to simulated parts of different specifications by adjusting the height and width, and has extremely strong applicability. When a fatigue test is performed using the high-temperature, high-cycle fatigue test method for a simulated turbine blade provided by the present invention, it is possible to detect whether the simulated part fails at high temperature based on the test results, and when the failure of the simulated part is detected, the test device can automatically and accurately obtain the number of fatigue times when the simulated part fails.

[0028] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings herein are incorporated into and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0030] Figure 1 A schematic structural diagram of a high-temperature, high-cycle fatigue test device for an aircraft engine turbine blade simulation component provided in accordance with an embodiment of the present disclosure.

[0031] Figure 2 A schematic diagram of a high temperature furnace heating box provided for an embodiment of the present disclosure.

[0032] Figure 3 A schematic diagram of a fixture cover provided for an embodiment of the present disclosure.

[0033] Figure 4 A schematic diagram of a fixture base provided for an embodiment of the present disclosure.

[0034] Figure 5 A schematic diagram of a test simulation component drawing provided for an embodiment of the present disclosure.

[0035] Figure 6 A schematic diagram of an upper plate of a water cooling plate provided in accordance with an embodiment of the present disclosure.

[0036] Figure 7 A schematic diagram of a chassis of a water cooling plate provided for an embodiment of the present disclosure.

[0037] Figure 8 A schematic diagram of assembling a simulation part and a tooling fixture is provided for an embodiment of the present disclosure.

[0038] Fig. 9 A flow chart of a high temperature and high cycle fatigue test method for an aircraft engine turbine blade simulation component provided in accordance with an embodiment of the present disclosure.

[0039] Description of reference numerals:

[0040] 10. Test device base; 11. Vibration test bench; 12. Water cooling plate; 121. Upper plate; 122. Lower plate; 13. Fixture base; 14. Fixture cover; 15. Simulation parts; 16. Test frame assembly; 17. Laser displacement sensor; 18. Acceleration sensor; 19. High temperature furnace heating system; 191. High temperature heating furnace box; 20. Temperature sensor; 21. Data acquisition and modal analysis equipment; 22. Vibration control and data analysis system; 23. Vibration control equipment; 24. Vibration test bench water cooling machine. DETAILED DESCRIPTION

[0041] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted.

[0042] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0043] The terms "a", "an", "the", and "said" are used to indicate the presence of one or more elements / components / etc.; the terms "including" and "having" are used to express an open-ended inclusion and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first" and "second" are used merely as labels and are not intended to limit the quantity of their objects.

[0044] In the related technology, the high-cycle fatigue performance of turbine blade simulation parts is studied by conducting material-level high-cycle fatigue tests, and the deformation of blade materials and the high-cycle fatigue failure mechanism can be analyzed. However, to study the high-cycle fatigue performance of turbine blade simulation parts at high temperatures, there are still problems such as the immaturity of heating technology and displacement measurement technology. The traditional high-cycle fatigue test method of electromagnetic induction heating of local areas cannot meet the high-cycle fatigue test requirements of simulation parts that need uniform heating. Therefore, this patent invents a high-cycle fatigue test device assembled with a high-temperature furnace and a vibration test bench for uniformly heating turbine blade simulation parts, aiming to achieve high-cycle fatigue tests on simulation parts that need uniform heating and achieve good displacement measurement effects, and obtain real high-cycle fatigue measurement results.

[0045] In response to the above technical problems, the present invention provides a high-temperature high-cycle fatigue test device and test method for aircraft engine turbine blade simulation parts, which replaces the traditional high-cycle fatigue test method of local area electromagnetic induction heating, solves the limitations of the traditional high-cycle fatigue test method of local heating simulation parts, and can be applied to turbine blade simulation parts of various specifications.

[0046] Specifically, Figure 1As shown, the high-temperature high-cycle fatigue test device for a simulated aircraft engine turbine blade provided by the present invention comprises: a vibration test bench 11, a water cooling plate 12, a fixture base 13, a fixture cover 14, a test frame assembly 16, a laser displacement sensor 17, an acceleration sensor 18, a high-temperature furnace heating system 19, a temperature sensor 20, a data acquisition and modal analysis device 21, a vibration control and data analysis system 22, a vibration control device 23 and a vibration test bench water cooler 24.

[0047] The vibration test bench 11 and the water cooling plate 12 constitute a vibration component of the test device, and the water cooling plate 12 is fixed on the vibration test bench 11. The water cooling plate 12 is detachably fixedly connected to the vibration test bench 11, for example, the water cooling plate 12 is fixed to the vibration test bench 11 by bolts; for example, Figure 6 and Figure 7 As shown, the water cooling plate 12 is provided with a plurality of hexagonal bolt holes; of course, the water cooling plate 12 and the vibration test table 11 can also be fixedly connected by means of clamping, bonding, welding, riveting, etc.

[0048] The water cooling plate 12 is provided with a water inlet pipe and a water outlet pipe at both ends, and the vibration test bench water cooling machine forms a water cooling cycle with the water cooling plate 12 through the water inlet pipe and the water outlet pipe, and is fixed on the ground. The water cooling plate 12 includes an upper plate 121 and a lower plate 122, and the upper plate 121 and the lower plate 122 are buckled together to form the water cooling plate 12.

[0049] Among them, Figure 3 to Figure 5 As shown, the fixture base 13 and the fixture cover 14 are combined to form a test fixture, and the fixture base 13 is fixed on the water cooling plate 12; Figure 8 As shown, the fixture base 13 and the fixture cover 14 cooperate to fix the dummy component 15. The fixture base 13 and the water cooling plate 12 are detachably connected. For example, the fixture base 13 can be fixed to the water cooling plate 12 by bolts; of course, the fixture base 13 and the water cooling plate 12 can also be fixedly connected by clamping, bonding, welding, riveting, etc. Figure 8 As shown, the fixture base 13 and the fixture cover 14 fix the dummy part 15 on the fixture by two bolts.

[0050] The acceleration sensor 18 is fixed on the vibration test bench 11 or the water cooling plate 12 to sense acceleration. The acceleration sensor 18 can be detachably fixed on the vibration test bench 11 or the water cooling plate 12. For example, the acceleration sensor 18 can be fixed on the vibration test bench 11 or the water cooling plate 12 by bolts; of course, the acceleration sensor 18 and the vibration test bench 11 or the water cooling plate 12 can also be fixedly connected by means of clamping, bonding, welding, riveting, etc.

[0051] Among them, the test frame assembly 16 is arranged corresponding to the work fixture base, the high-temperature furnace heating system 19 is fixed on the water cooling plate 12 through the test frame assembly 16, and the heating plate of the high-temperature heating furnace box 191 covers around the tooling fixture base 13 and the tooling fixture cover plate 14 to heat the simulation part 15.

[0052] Among them, Figure 2 As shown, the probe of the temperature sensor 20 can be placed around the simulation part 15 through the observation window glass plate of the high-temperature furnace heating system 1919 to measure the temperature.

[0053] Among them, the test frame assembly 16 is set corresponding to the work fixture base, and the laser displacement sensor 17 is installed on the test frame assembly 16, which can be adjusted on the test frame assembly 16 according to the position of the displacement to be measured; the laser displacement sensor 17 collects incident light and reflected light data through the glass cover plate on the upper surface of the high-temperature furnace heating system 19.

[0054] The test frame assembly 16 includes a vertical support assembly and a horizontal mounting rod structure. The horizontal mounting rod is fixed between the two vertical support assemblies. The horizontal mounting rod is provided with a groove that enables the laser displacement sensor 17 to move. The surface of the vertical support assembly is provided with a groove, and the height can be adjusted according to the needs; holes that match the groove holes on the surface of the vertical support assembly are provided on both sides of the horizontal mounting rod, and the vertical support assembly and the horizontal mounting rod are connected by bolts. By removing the bolts, the position of the horizontal mounting rod in the test frame assembly 16 is adjusted, so that the position of the bolt hole on the horizontal mounting plate is aligned and fixed with the bolt holes on different layers of the vertical support assembly, and the spacing between the horizontal mounting plate and the test device base 10 is adjusted so that the test device can adapt to laser displacement sensors 17 of different specifications. The surface of the horizontal rod is provided with a long strip of through holes, and the through holes are provided with through holes that match the bolts.

[0055] Among them, the data acquisition and modal analysis equipment 21 and the vibration control equipment 23 are connected to the vibration control and data analysis system 22 through communication cables, the vibration control equipment 23 is connected to the vibration test bench 11 through communication cables, the operation panel and the vibration control equipment 23 and the vibration control and data analysis system 22 control the vibration test bench and set relevant parameters to carry out high-cycle fatigue tests, and the data acquisition and modal analysis equipment 21 collects high-cycle fatigue test data.

[0056] The test device also includes a base, and the test frame assembly 16 and the vibration test table are fixed on the base. Tripods are arranged at both ends of the horizontal mounting plate to facilitate the assembly and movement of the whole device.

[0057] Among them, Figure 2As shown, one end of the temperature sensor probe is inserted into the furnace box through the glass hole above the high-temperature furnace, and the other end is connected to the temperature sensor. The data acquisition and modal analysis equipment 21 and the vibration control equipment 23 are connected to the vibration control and data analysis system 22 through communication cables.

[0058] Among them, the data acquisition and modal analysis equipment 21 has eight channels, the maximum sampling rate of each channel is 2019 for the high-temperature furnace heating system 194.8kHz, and each channel has an independent LED status display light.

[0059] The range of the acceleration sensor 18 is 500g, the sensitivity is 10.42mV / g, and the resolution is 0.0015g.

[0060] Among them, the laser displacement sensor 17 can be used to measure the displacement of high-temperature objects. Its model is ILD23, which is a vibration control and data analysis system 22 10-50BL. Its linear range is 50mm, the sampling frequency range is 1.5KHz~49KHz, the resolution is 7.5um, and the sensor is also equipped with a dual-channel multi-function processor.

[0061] The high temperature furnace heating system 19 is equipped with a water chiller, a heater and an infrared thermometer. The water in and out of the heater forms a cycle to cool the high temperature furnace, and the compressor absorbs the heat of the water in the water tank and discharges it through the fan. The heating system can achieve temperature maintenance, and the range of temperature maintenance is determined by the temperature measurement range of the infrared thermometer. The infrared thermometer can measure temperatures in the range of 600℃ to 1400℃, so the heating system can achieve any temperature maintenance in the range of 600℃ to 1400℃.

[0062] Among them, the vibration test bench 11 model is ES-10D-24, which is the vibration control equipment 2323, with a rated sinusoidal excitation force of 10KN and a maximum acceleration of 1000m / s 2 , the rated displacement is 51mm; the vibration test bench 11 is also equipped with a cooling fan, a power amplifier, a vibration controller, a horizontal slide table and a vertical extension table. The vibration control device 23 generates a sinusoidal signal of a specific frequency, amplifies the signal using a power amplifier, and then converts the periodic electrical signal into mechanical motion through an electromagnetic coil.

[0063] The object can be fixed on a vertical expansion table to achieve vertical vibration, and can be fixed on a horizontal sliding table to achieve horizontal vibration.

[0064] Among them, a groove with a depth of 2 mm is opened in the assembly surface of the fixture base 13 and the fixture cover 14, which is consistent with the geometric characteristics of the simulation part 15 and constrains the displacement of the simulation part 15 in the X and Y directions to 0 mm.

[0065] The present invention provides a high-temperature, high-cycle fatigue test device for an aircraft engine turbine blade simulation part 15. Compared with the traditional fatigue test method using electromagnetic induction heating, the test device provided by the present invention has low construction cost, is easy to maintain, flexible to install and easy to operate, does not require large-scale infrastructure construction and a large number of personnel to conduct test tracking, and reduces labor costs; the test device provided by the present invention can be applied to simulation parts 15 of different specifications by adjusting the height and width, and has extremely strong applicability; when a fatigue test is performed using the high-temperature, high-cycle fatigue test method for a turbine blade simulation part 15 provided by the present invention, it is possible to detect whether the simulation part 15 fails at high temperature based on the test results, and when the failure of the simulation part 15 is detected, the test device can automatically and accurately obtain the number of fatigue times when the simulation part 15 fails.

[0066] The present disclosure also provides a high temperature high cycle fatigue test method for an aircraft engine turbine blade simulation part 15, such as Fig. 9 As shown, the experimental method specifically includes the following steps:

[0067] Step S100: Performing an air tightness test on the water cooling plate 12 to ensure that the cooling capacity and air tightness of the water cooling plate 12 meet the design requirements;

[0068] Step S2019 is the high temperature furnace heating system 190: turning on the vibration control device 23 to start the fatigue test device;

[0069] Step S21 is for temperature sensor 0: Open the vibration control and data analysis system 22 to enter the fatigue test parameter setting interface, preset the fatigue times to 107 times, the test frequency to a certain order natural frequency of the simulation component 15, the upper limit of displacement to +10mm, and the lower limit of displacement to -10mm. Start the vibration table controller to start the high cycle fatigue test;

[0070] Step S300: Performing a modal test on the simulation component 15:

[0071] Step S310: Testing is performed by a force hammer excitation method, and the mobile force hammer method adopts a multi-point excitation and single-point measurement method. Before the test, it is necessary to complete the establishment of a geometric model in the modal analysis software based on the geometric shape of the simulation part 15;

[0072] Step S32019 is the high temperature furnace heating system 19: the acceleration sensor 18 is pasted to an excitation point of the simulation component 15, and the corresponding excitation point is knocked according to the instruction in the modal analysis software, and the acceleration sensor 18 can obtain the acceleration response of the point. After the signal collection of all points is completed, the modal parameters of the simulation component 15 can be identified through the modal analysis system;

[0073] Step S400: Combine the finite element analysis results with the strain measurement results of the simulation part 15 to calibrate the stress at the maximum stress position of the simulation part 15. And use the indirect method to calibrate the stress at high temperature. The specific process of the vibration stress calibration test is as follows:

[0074] Step S410: determine the position of the strain measurement point, and select a position with greater stress near the clamping end of the simulation component 15 to paste the strain gauge;

[0075] Step S42019 is the high temperature furnace heating system 19: using the vibration test bench to perform a resonance dwell test on the simulation component 15 at the target order, measuring the vibration response of the simulation component 15 at the first order resonance state, recording its strain amplitude at different amplitudes, and using a linear fitting method to obtain a relationship curve between the two;

[0076] Step S430: The determination of the proportionality coefficient K is based on the results of the finite element analysis. It is necessary to perform a finite element harmonic response analysis on the simulation component 15, the fixture as a whole, and the model. Given the overall displacement amplitude, the stress cloud diagram of the simulation component 15 as a whole and the test section is obtained. The stress of all nodes in the area corresponding to the strain gauge pasting position is extracted, and the average stress value in the area is calculated. The stress value is the stress value at the strain gauge measuring point and the maximum stress value of the simulation component 15. The proportionality coefficient K can be obtained by dividing the latter stress value by the former stress value.

[0077] Step S440: The relationship between the end displacement of the simulation component 15 and the strain at the measuring point measured at room temperature is used to approximately replace the relationship between the end displacement of the simulation component 15 and the strain at the measuring point under high temperature. The strain value is multiplied by the elastic modulus at the corresponding temperature to obtain the stress value at the corresponding temperature, and the stress value at the corresponding temperature is multiplied by the proportionality coefficient K to obtain the maximum stress of the simulation component 15 at high temperature, which is the stress level of the high cycle fatigue test.

[0078] Step S500: First, perform a frequency sweep test on the installed and fixed simulation part 15 at room temperature, and record the natural frequency of the simulation part 15. Then set the heating program of the high-temperature furnace heating controller, heat the simulation part 15, and when the temperature of the simulation part 15 reaches the target temperature, keep it warm for 10 minutes and perform a high-temperature frequency sweep test, record the first-order natural frequency of the simulation part 15, the upper limit of displacement is +10mm, and the lower limit of displacement is -10mm. Finally, a high-cycle fatigue test is performed by tracking and dwelling to control the amplitude during the test.

[0079] Step S600: Setting the test termination condition, taking the natural frequency of the simulation part 15 decreasing by 2% or obvious cracks appearing on the surface of the simulation part 15 as the test termination condition; or, the test will be terminated when the number of test cycles reaches 107 times.

[0080] In some embodiments of the present invention, after the simulated component 15 to be tested is installed on the test fixture, the main power switch is turned on, and the water cooler of the vibration test bench is turned on. The vibration control and data analysis system 22 is turned on to enter the fatigue test parameter setting interface, and the preset fatigue times are 107 times, the test frequency is a certain order natural frequency of the simulated component 15, the upper limit of displacement is +10mm, and the lower limit of displacement is -10mm.

[0081] The present invention provides a high-temperature and high-cycle fatigue test method for an aircraft engine turbine blade simulation part 15. When conducting a fatigue test, it is possible to detect whether the simulation part 15 fails at a high temperature based on the test results. When the failure of the simulation part 15 is detected, the test device can automatically and accurately obtain the fatigue times when the simulation part 15 fails.

[0082] It should be noted that, although the steps of the method in the present disclosure are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0083] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the following claims.

[0084] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A high temperature and high cycle fatigue test device for a simulated aircraft engine turbine blade, characterized in that: include: Vibration test bench, water cooling plate, fixture base, fixture cover, test frame assembly, laser displacement sensor, acceleration sensor, high temperature furnace heating system, temperature sensor, data acquisition and modal analysis equipment, vibration control and data analysis system, vibration control equipment and vibration test bench water cooling machine; wherein, the water cooling plate is fixed on the vibration test bench, and the vibration test bench water cooling machine forms a water cooling cycle with the water cooling plate through a water inlet pipe and a water outlet pipe; the fixture base is fixed on the water cooling plate, and the fixture base cooperates with the fixture cover to fix the simulation part; the test frame assembly is arranged correspondingly to the work fixture base, The laser displacement sensor is adjustably mounted on the test frame assembly; the acceleration sensor is fixed on the vibration test bench or the water cooling plate to sense acceleration; the high-temperature furnace heating system is fixed on the water cooling plate, and the heating plate of the high-temperature furnace heating system covers around the fixture base and the fixture cover to heat the simulation part; the probe of the temperature sensor is placed around the simulation part through the observation window glass plate of the high-temperature furnace heating system to measure the temperature; the data acquisition and modal analysis equipment, the vibration control and data analysis system, the vibration control equipment and the vibration test bench are connected by communication cables.

2. The fatigue testing device according to claim 1, characterized in that: The test frame assembly includes a vertical support assembly and a horizontal mounting rod structure. Holes that match the groove holes on the surface of the vertical support assembly are arranged on both sides of the horizontal mounting rod. The vertical support assembly and the horizontal mounting rod are connected by bolts; the horizontal mounting rod is provided with a groove that enables the laser displacement sensor to move.

3. The fatigue testing device according to claim 1, characterized in that: The fixture base and the fixture cover assembly surface are each provided with a groove for matching and fixing the simulation part.

4. The fatigue testing device according to claim 1, characterized in that: The test device also includes a base, and the test frame assembly and the vibration test table are both fixed on the base.

5. The fatigue testing device according to claim 1, characterized in that: The data acquisition and modal analysis device has eight channels, each channel has a maximum sampling rate of 204.8 kHz and has an independent LED status display light.

6. The fatigue testing device according to claim 1, characterized in that: The accelerometer has a range of 500g, a sensitivity of 10.42mV / g, and a resolution of 0.0015g.

7. The fatigue testing device according to claim 1, characterized in that: The linear range of the laser displacement sensor is 50 mm, the sampling frequency range is 1.5 KHz to 49 KHz, and the resolution is 7.5 um.

8. The fatigue testing device according to claim 1, characterized in that: The rated sinusoidal excitation force of the vibration test bench is 10KN and the maximum acceleration is 1000m / s 2 , rated displacement is 51mm.

9. A high temperature and high cycle fatigue test method for a simulated aircraft engine turbine blade, characterized in that: include: Provide a fatigue testing device as described in any one of claims 1 to 8; Conducting an air tightness test on the water cooling plate of the fatigue test device to ensure that the cooling capacity and air tightness of the water cooling plate meet the preset conditions; Turning on the vibration control device to start the fatigue test device; The test is carried out by the force hammer excitation method. The mobile force hammer method adopts the method of multi-point excitation and single-point measurement. Before the test, it is necessary to complete the establishment of the geometric model in the modal analysis software based on the geometric shape of the simulated part. The acceleration sensor is pasted to an excitation point of the simulated part, and the corresponding excitation point is knocked according to the instructions in the modal analysis software. The acceleration sensor can obtain the acceleration response of the point. After the signal acquisition of all points is completed, the modal parameters of the simulated part are identified through the modal analysis system. The stress at the maximum stress position of the simulated part is calibrated by combining the finite element analysis results with the strain measurement results of the simulated part, and the stress at high temperature is calibrated by the indirect method; A frequency sweep test is performed on the installed and fixed simulation part at room temperature, and the natural frequency of the simulation part is recorded; then the heating program of the high-temperature furnace heating controller is set to heat the simulation part. When the temperature of the simulation part reaches the target temperature, it is kept warm for ten minutes and a high-temperature frequency sweep test is performed to record the first-order natural frequency of the simulation part; finally, a high-cycle fatigue test is performed by tracking and dwelling to control the amplitude during the test; The test termination conditions are set to be the natural frequency of the simulated part dropping by 2% or the appearance of obvious cracks on the surface of the simulated part; or, the test cycle number reaches 10. 7 The test was terminated.

10. The fatigue testing method according to claim 9, characterized in that: The vibration stress calibration test includes: Determine the location of the strain measurement point and select the location with greater stress near the clamping end of the simulation part to paste the strain gauge; The vibration test bench is used to perform a resonance dwell test on the simulation component at a target order, the vibration response of the simulation component in a first-order resonance state is measured, the strain amplitude at different amplitudes is recorded, and a relationship curve between the two is obtained by linear fitting; The determination of the proportionality coefficient K is based on the results of finite element analysis. It is necessary to perform finite element harmonic response analysis on the simulation component, the fixture as a whole, and the model. Given the overall displacement amplitude, the stress cloud diagram of the simulation component as a whole and the test section is obtained; the stress of all nodes in the area corresponding to the strain gauge pasting position is extracted, and the average stress value in the area is calculated. The stress value is the stress value at the strain gauge measuring point and the maximum stress value of the simulation component. The proportionality coefficient K can be obtained by dividing the latter stress value by the former stress value; The relationship between the end displacement of the simulated component and the strain at the measuring point measured at room temperature is used to approximately replace the relationship between the end displacement of the simulated component and the strain at the measuring point under high temperature; the strain value is multiplied by the elastic modulus at the corresponding temperature to obtain the stress value at the corresponding temperature, and the stress value at the corresponding temperature is multiplied by the proportional coefficient K to obtain the maximum stress of the simulated component at high temperature. This maximum stress value is the stress level of the high cycle fatigue test.

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