Turbine blade thermal fatigue test method and test device

Abstract

The invention provides a turbine blade thermal fatigue test method and device, and relates to the technical field of turbine blade high-temperature durability tests.The test method comprises the following steps that S1, a test piece is installed, and emissivity test position consistency is adjusted; s2, heating the test piece to a set temperature under a gas working condition, and adjusting the emissivity of the pyrometer to enable the temperature of the pyrometer to be consistent with the set temperature; and S3, installing a turbine blade test piece, and carrying out a fatigue test on the thermal barrier coating of the turbine blade. According to the invention, the gas working conditions of the tester can be rapidly switched, the emissivity of the thermal barrier coating of the turbine blade under the test gas condition can be accurately tested, and the cycle period curve of the thermal fatigue test of the turbine blade can be effectively established.

Description

Technical Field

[0001] This invention relates to the field of high-temperature durability testing technology for turbine blades, specifically to a method and apparatus for testing the thermal fatigue of turbine blades. Background Technology

[0002] In recent years, with the development of the aviation industry, in order to improve the performance of aero engines and increase their thrust-to-weight ratio, the turbine inlet gas temperature of aero engines has been getting higher and higher. The significantly increased gas temperature poses a great challenge to the heat resistance of aero engine turbine blade materials.

[0003] Currently, in aero-engine research worldwide, turbine blades are being improved in terms of heat resistance through two main approaches: materials and thermal protection. In terms of materials, the development is iterating from high-temperature single-crystal alloys to ceramic matrix composites. Thermal protection technologies primarily include cooling film pore technology and thermal barrier coating (TBC) technology. Cooling film pore technology comes at the cost of turbine performance, while TBC is a coating material with high temperature resistance, low thermal conductivity, and excellent thermal insulation properties. Research shows that under certain conditions, a 150μm thick TBC can achieve thermal isolation of approximately 150℃. Therefore, TBC is a widely used thermal protection method for engine turbine blades.

[0004] During turbine blade service, the gas temperature fluctuates drastically during takeoff, cruise, and landing. Prolonged operation under high temperature and high load conditions reduces the reliable service life of the blade coating, leading to failures such as high-temperature oxidation and thermal fatigue. To improve engine efficiency and performance, it is essential to conduct high-temperature resistance tests on blades with different airfoil parameters and coating processes, simulating the environment of aero-engines—the turbine blade thermal barrier coating thermal fatigue test. These tests refine the coating process technology, continuously iterating and improving the turbine blades' ability to withstand high-temperature environments.

[0005] Temperature spectrum of thermal fatigue test of turbine blade thermal barrier coating as shown in the figure Figure 1 As shown in the figure, to simulate the service environment of turbine blades, the temperature curve of the turbine blades during the thermal fatigue test cycle is divided into three stages: rapid heating, high-temperature holding, and rapid cooling. Different airflow conditions should be switched for different temperature stages. The cooling stage is generally achieved by blowing cold air onto the test piece. However, during the rapid heating and high-temperature holding stages, the gas conditions of the test instrument need to be switched rapidly. Currently, the gas temperature of the test instrument is generally adjusted by regulating the fuel system control valve. This adjustment method takes a long time and is prone to temperature overshoot.

[0006] In addition, the temperature of the turbine blade coating surface needs to be accurately measured during the experiment to adjust the temperature periodicity spectrum. Since the thermal barrier coating of aero-engine turbine blades is very thin and its physical properties do not allow for the placement of thermocouples, there are currently two main methods for measuring the temperature of the turbine blade thermal barrier coating: one is to use thermocouples to measure the temperature at different locations on the substrate and calculate the outer surface temperature of the coating based on the temperature difference and material properties using thermodynamic knowledge; the other is to use a pyrometer (infrared thermometer) to measure the temperature of the turbine blade surface thermal barrier coating by heating the sample in a high-temperature furnace to calibrate the emissivity at different temperatures.

[0007] However, both methods have their shortcomings to varying degrees: When using thermocouples, the thickness of the turbine blade substrate material (~1.5mm) is insufficient relative to the size of the test object (minimum 0.2mm), leading to a deviation in the correlation between temperature and position. Furthermore, in thermodynamic calculations, a significant portion of the heat flow occurs along the film gas vents in addition to the direction perpendicular to the turbine blade thickness, resulting in inaccuracies in heat flux density calculations. When calibrating emissivity using a high-temperature furnace, the brightness, radiation, and composition of the furnace gas environment differ from the actual service combustion environment of an engine. These factors influence emissivity, causing measurement deviations and affecting the accuracy of temperature measurements. Additionally, the multi-dimensional curved surface of engine blades makes it difficult to simulate the measurement angle of the measured point in the furnace environment, further impacting the accuracy of emissivity measurements.

[0008] In view of this, the inventors of this application have designed a method and apparatus for testing the thermal fatigue of turbine blades in order to overcome the above-mentioned technical problems. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to overcome the shortcomings of the existing turbine blade thermal fatigue test, and to provide a turbine blade thermal fatigue test method and test device.

[0010] The present invention solves the above-mentioned technical problems through the following technical solution:

[0011] This invention provides a method for testing the thermal fatigue of turbine blades, characterized in that the method includes the following steps: S1, installing the test specimen and adjusting the consistency of the emissivity test position; S2, heating the test specimen to a set temperature under gas conditions, and adjusting the emissivity of the pyrometer to make the pyrometer temperature consistent with the set temperature; S3, installing the turbine blade test piece and conducting a fatigue test on the thermal barrier coating of the turbine blade.

[0012] According to one or more embodiments of the present invention, step S1 includes the following sub-steps: S 11Adjust the position and measuring angle of the pyrometer; adjust the test position and angle of the test specimen to match the test position and angle of the turbine blade test piece; S 12 Ensure that the material and coating of the test specimen are consistent with those of the turbine blade test piece, and pre-embed a thermocouple in the center of the test specimen to ensure that the thermocouple measuring point corresponds to the pyrometer measuring point.

[0013] According to one or more embodiments of the present invention, step S2 includes the following sub-steps: S 21 The test specimen is heated by a gas nozzle until the temperature of the thermocouple embedded in the specimen reaches the high-temperature holding temperature T1; the emissivity of the pyrometer is adjusted so that the pyrometer temperature matches the thermocouple temperature, at which point the pyrometer emissivity is the high-temperature holding temperature emissivity K1; S 22 1. Heat the test specimen with a hot air gun until the temperature of the thermocouple embedded in the test specimen reaches the low temperature T2; 2. Adjust the emissivity of the pyrometer so that the temperature of the pyrometer and the temperature of the thermocouple are consistent. At this time, the emissivity of the pyrometer is the emissivity K2 of the cooled low temperature.

[0014] According to one or more embodiments of the present invention, in step S3, each cycle of the turbine blade thermal barrier coating fatigue test includes a rapid heating stage, a high temperature holding stage, and a rapid cooling stage, and adjustments need to be made for the rapid heating condition, the high temperature holding condition, and the rapid cooling condition.

[0015] According to one or more embodiments of the present invention, when performing high-temperature holding condition debugging, the turbine blade test piece is placed at the gas nozzle position, the emissivity of the pyrometer is adjusted to the high-temperature holding temperature emissivity K1, so that the pyrometer temperature reaches the high-temperature holding temperature T1 and remains stable, and the valve position m of the control valve of the first oil circuit of the fuel system is recorded.

[0016] According to one or more embodiments of the present invention, during rapid cooling condition debugging, the turbine blade test piece is placed at the gas nozzle position, and the emissivity of the pyrometer is adjusted to the high-temperature holding temperature emissivity K1; after the pyrometer temperature reaches the high-temperature holding temperature T1 and stabilizes, the pyrometer emissivity is adjusted to the cooling low-temperature point temperature emissivity K2. At this time, the turbine blade test piece is moved to the cold air nozzle position and the turbine blade test piece is cooled by cold air. After the pyrometer temperature reaches the low-temperature point temperature T2, the cooling rate is recorded; according to the cooling rate, the above steps are repeated, and the cold air flow rate is adjusted until the cooling rate of the turbine blade test piece meets the expected value. At this time, the cold air control valve position n% and the cooling time t3 of the rapid cooling stage of the turbine blade test piece are recorded.

[0017] According to one or more embodiments of the present invention, during rapid heating condition debugging, the turbine blade test piece is placed at the cold air nozzle position, and the emissivity of the pyrometer is adjusted to the high-temperature holding temperature emissivity K1; the control valve position of the first fuel system circuit is maintained at m%; the second fuel system circuit is operated, and the turbine blade test piece is moved to the gas nozzle position. When the pyrometer temperature reaches the high-temperature holding temperature T1, the turbine blade test piece is moved to the cold air nozzle position, and the pyrometer emissivity is adjusted to the cooling low-temperature temperature emissivity K2; when the pyrometer temperature drops to the low-temperature temperature T2, the turbine blade test piece is moved to the gas nozzle position, and the pyrometer emissivity is adjusted to the high-temperature holding temperature emissivity K1. When the pyrometer temperature rises to the high-temperature holding temperature T1, the heating rate is recorded; according to the heating rate, the above steps are repeated, and the second fuel system circuit is adjusted until the heating rate of the turbine blade test piece meets the expected value. The valve position w% of the control valve of the second fuel system circuit and the heating time t1 are recorded.

[0018] This invention also provides a turbine blade thermal fatigue testing apparatus, characterized in that the apparatus is used to perform the turbine blade thermal fatigue testing method described above. The apparatus includes a combustion chamber, a fuel system, a pyrometer, and a test bench. A gas nozzle is disposed on the side of the combustion chamber, facing the test bench, and gas is ejected through the gas nozzle to heat the turbine blade test piece and / or test specimen. The fuel system is connected to the combustion chamber and is used to provide the test gas conditions. The pyrometer is connected to the test bench and is used to measure the temperature of the turbine blade test piece and / or test specimen. The test bench is provided with an mounting structure for mounting the turbine blade test piece and / or test specimen.

[0019] According to one or more embodiments of the present invention, the test apparatus further includes a cooling system, wherein the cooling nozzles of the cooling system are disposed facing the test bench, and the cooling system is used to cool the turbine blade test piece and / or test specimen.

[0020] According to one or more embodiments of the present invention, the fuel system is a dual-line dual-nozzle fuel system, including a first fuel line and a second fuel line, each fuel line including a fuel supply line and a fuel return line;

[0021] One end of the fuel supply circuit is connected to the fuel station, and the other end is connected to the fuel injector, which is located in the combustion chamber. The fuel supply circuit is sequentially connected to a fuel pump, a flow meter, a control valve, a switching valve, and a check valve along the fuel flow direction. One end of the return fuel circuit is connected to the fuel pump, and the other end is connected to the fuel station. The return fuel circuit is sequentially connected to a pressure regulating overflow valve and a cooler along the fuel flow direction. The first fuel circuit is used to regulate the first gas condition, maintain the fuel pump frequency and overflow valve pressure at a constant level, and debug the turbine blade test piece under the first gas condition. When the debugging is completed, the control valve position of the first fuel circuit remains unchanged, the switching valve is normally open, and the combustion chamber burns normally. The second fuel circuit regulates the second gas condition by adjusting the fuel supply. After the debugging is completed, the switching of the first gas condition and the second gas condition is realized by opening and closing the switching valves of the first fuel circuit and the second fuel circuit.

[0022] According to one or more embodiments of the present invention, after completing the debugging of the rapid heating condition, the high temperature holding condition, and the rapid cooling condition, the following settings are made: During the rapid heating phase of the turbine blade thermal barrier coating fatigue test cycle, the pyrometer emissivity is set to K1, the switch valve in the first oil circuit is open, the control valve in the first oil circuit is at a position of m%, the switch valve in the second oil circuit is open, the control valve in the second oil circuit is at a position of w%, and the cooling gas switch valve is closed. During the high temperature holding phase of the turbine blade thermal barrier coating fatigue test cycle, the pyrometer emissivity is set to K1, the switch valve in the first oil circuit is open, the control valve in the first oil circuit is at a position of m%, the switch valve in the second oil circuit is closed, and the cooling gas switch valve is closed. During the rapid cooling phase of the turbine blade thermal barrier coating fatigue test cycle, the pyrometer emissivity is set to K2, the switch valve in the first oil circuit is open, the control valve in the first oil circuit is at a position of m%, the switch valve in the second oil circuit is closed, the cooling gas switch valve is open, and the cooling gas control valve is at a position of n.

[0023] According to one or more embodiments of the present invention, the mounting structure includes a test specimen mounting and adjusting device, and the test bench is further provided with a pyrometer adjusting device; the test specimen mounting and adjusting device is used to fix the test specimen and adjust the position and angle of the test specimen; the pyrometer adjusting device is used to adjust the position and temperature measuring angle of the pyrometer.

[0024] According to one or more embodiments of the present invention, the test specimen mounting and adjusting device includes a test specimen mounting ring and an adjusting platform; the adjusting platform is movably connected to the test bench; the test specimen mounting ring is fixed on the adjusting platform, and the adjusting platform is adjustable in height, tilt, and horizontal position; the test specimen is movably connected to the test specimen mounting ring, and the test specimen can rotate within the test specimen mounting ring.

[0025] According to one or more embodiments of the present invention, the test piece mounting and adjusting device further includes a test piece adjusting bolt, and the test piece mounting ring is provided with a sliding groove; one end of the test piece adjusting bolt is connected to the end of the test piece, and the other end of the test piece adjusting bolt is connected to the sliding groove; the test piece is rotated within the test piece mounting ring by adjusting the connection position of the test piece adjusting bolt in the sliding groove.

[0026] According to one or more embodiments of the present invention, the test specimen mounting and adjusting device further includes a platform adjusting screw and a platform adjusting nut; the adjusting platform is movably connected to the test bench via the platform adjusting screw and the platform adjusting nut, one end of the platform adjusting screw is connected to the test bench, and the other end of the platform adjusting screw is connected to the adjusting platform; the platform adjusting nut is threadedly connected to the platform adjusting screw, and the platform adjusting nut limits the adjustment platform; by adjusting the connection position of the platform adjusting nut on the platform adjusting screw, the height and tilt of the adjusting platform can be adjusted.

[0027] According to one or more embodiments of the present invention, the test specimen mounting and adjusting device further includes a slide rail and a slider; the adjusting platform is movably connected to the test bench through the slide rail and the slider, the adjusting platform is connected to the slider, and the slider is slidably connected to the slide rail.

[0028] The positive and progressive effects of this invention are as follows:

[0029] The turbine blade thermal fatigue testing method and apparatus of this invention can achieve accurate measurement of coating surface temperature and establishment of temperature cycling curves during turbine blade thermal fatigue testing, thereby realizing:

[0030] I. Rapid switching of gas conditions in the tester.

[0031] II. Precise testing of emissivity of thermal barrier coating on turbine blades under test gas conditions.

[0032] III. Effective establishment of cycle curves for thermal fatigue testing of turbine blades. Attached Figure Description

[0033] The above and other features, properties and advantages of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings and embodiments, in which the same reference numerals always denote the same features, wherein:

[0034] Figure 1 This is a typical temperature spectrum for turbine blade thermal fatigue testing.

[0035] Figure 2 This is a schematic diagram of a dual-oil-circuit dual-nozzle fuel system in one embodiment of the turbine blade thermal fatigue testing device of the present invention.

[0036] Figure 3 This is a schematic diagram of an embodiment of the turbine blade thermal fatigue testing device of the present invention.

[0037] Figure 4 This is a schematic diagram of the structure used for adjusting the consistency of the emissivity test position in one embodiment of the turbine blade thermal fatigue test device of the present invention.

[0038] Figure 5 This is a schematic diagram of the structure of the test specimen installation and adjustment device in one embodiment of the turbine blade thermal fatigue testing device of the present invention.

[0039] Figure 6 This is a schematic diagram of the test specimen used in the turbine blade thermal fatigue test method and test device of the present invention.

[0040] Figure 7 This is a curve of the theoretical temperature cycle in the turbine blade thermal fatigue test method of the present invention.

[0041] Figure 8 This is a schematic diagram of the hot end position of the test piece in the turbine blade thermal fatigue test method of the present invention.

[0042] Figure 9 This is a schematic diagram of the cold end position of the test piece in the turbine blade thermal fatigue test method of the present invention.

[0043] Figure 10 This is a curve of the actual temperature cycle in the turbine blade thermal fatigue test method of the present invention.

[0044] Figure 11 This is a schematic flowchart of an embodiment of the turbine blade thermal fatigue test method of the present invention. Detailed Implementation

[0045] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0046] Reference will now be made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used in all the drawings to denote the same or similar parts. Furthermore, although the terminology used herein is selected from commonly known and used terms, some terms mentioned in this specification may have been chosen by the applicant at his or her discretion, and their detailed meanings are explained in the relevant sections of the description herein. Moreover, the invention should be understood not only by the actual terminology used, but also by the meaning implied by each term. Also, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale.

[0047] See Figure 11 This invention provides a method for testing the thermal fatigue of turbine blades, the method comprising the following steps:

[0048] Step S1: Install the test specimen 610 and adjust the consistency of the emissivity test position.

[0049] Step S2: Heat the test specimen 610 to the set temperature under gas conditions, and adjust the emissivity of the pyrometer to make the pyrometer temperature consistent with the set temperature.

[0050] Step S3: Install turbine blade test piece 620 and conduct a fatigue test of the turbine blade thermal barrier coating.

[0051] It should be noted that steps S1 and S2 involve measuring the emissivity of the thermal barrier coating, and calibrating the emissivity of the pyrometer using a test specimen 610 with a thermal barrier coating.

[0052] exist Figure 11 In one embodiment, after the thermal barrier coating emissivity measurement was completed in steps S1 and S2, the period curve of the thermal fatigue test of the turbine blade thermal barrier coating was adjusted.

[0053] Since the temperature curve of the fatigue test of the thermal barrier coating of turbine blades includes three stages in each cycle: rapid heating stage, high temperature holding stage, and rapid cooling stage, at least three different operating conditions are required to ensure the temperature target and heating / cooling rate requirements of the test piece in the three stages: rapid heating condition A, high temperature holding condition B, and rapid cooling condition C.

[0054] The period curve debugging of the thermal fatigue test of the thermal barrier coating of turbine blades is to adjust the test parameters of three working conditions: rapid heating condition A, high temperature holding condition B, and rapid cooling condition C.

[0055] When conducting emissivity testing of thermal barrier coatings, the turbine blade thermal fatigue testing device of this invention provides a test gas environment. Since the turbine blade is a curved irregular structure, the measuring point has different positional relationships with the gas and the pyrometer 200 during different blade tests. In order to ensure the consistency of the measurement angle and distance of the measured position during emissivity testing and turbine blade testing, the test piece is adjusted by the emissivity measuring device to make the test position and angle consistent with the real blade, so as to simulate the real test conditions.

[0056] In a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, step S1 includes the following sub-steps:

[0057] Step S 11 Adjust the position and temperature measurement angle of the pyrometer 200; adjust the test position and angle of the test specimen 610 to match the test position and angle of the turbine blade test piece 620.

[0058] Step S 12 Ensure that the material and coating of the test specimen 610 are consistent with those of the turbine blade test piece 620. Pre-embed a thermocouple at the center of the test specimen 610 to ensure that the thermocouple measuring point corresponds to the measuring point of the pyrometer 200.

[0059] Preferably, it can be achieved through Figure 4 As shown, the consistency adjustment of the emissivity test position can be achieved through structures such as the pyrometer bracket 510, the spherical adjustment device 520, the sample mounting ring 420, the platform adjustment screw 450, and the platform adjustment nut 460.

[0060] Before adjustment, the installed turbine blade test piece 620 is inspected, and the installation angle is measured. Simultaneously, the position and angle of the pyrometer 200 are adjusted using the structure of the pyrometer bracket 510 and the spherical adjustment device 520. Then, the test piece mounting ring 420 is installed, and the angle of the test piece 610 is adjusted using the structure of the test piece mounting ring 420, the platform adjusting screw 450, and the platform adjusting nut 460, ensuring that the angle of the tested position of the test piece 610 matches the measured position of the turbine blade test piece 620.

[0061] Through the above steps, the test conditions of test specimen 610 and turbine blade test piece 620 are finally made consistent.

[0062] like Figure 3 As shown in the figure, the high temperature meter bracket 510 is mounted on the stand panel through an oval hole, which allows the position of the high temperature meter 200 to be adjusted in the X-axis direction. The spherical adjustment device 520 at the upper end of the high temperature meter bracket 510 can adjust the temperature measurement direction of the high temperature meter 200.

[0063] Preferably, the test specimen 610 is as follows: Figure 6 As shown, the dimensions are 150×20×2mm (length×width×thickness). A thermocouple is pre-embedded at the center of the test specimen 610. The material of the test specimen 610 is the same as that of the turbine blade test piece 620, with a double-sided TBC coating. The plane positions of the pyrometer 200 measuring point and the thermocouple measuring point on the turbine blade test piece 620 are consistent.

[0064] In a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, step S2 includes the following sub-steps:

[0065] Step S 21 The test specimen 610 is heated by the gas nozzle 141 so that the temperature of the thermocouple embedded in the test specimen 610 reaches the high temperature holding temperature T1; the emissivity of the pyrometer is adjusted so that the temperature of the pyrometer and the temperature of the thermocouple are consistent. At this time, the emissivity of the pyrometer is the emissivity of the high temperature holding temperature K1.

[0066] Step S 22 The test specimen 610 is heated by a hot air gun until the temperature of the thermocouple embedded in the test specimen 610 reaches the low temperature T2. The emissivity of the pyrometer is adjusted so that the temperature of the pyrometer and the temperature of the thermocouple are the same. At this time, the emissivity of the pyrometer is the emissivity K2 of the cooled low temperature.

[0067] After completing the installation and adjustment of test specimen 610 as described above, the emissivity test of the thermal barrier coating is carried out. The specific method is as follows:

[0068] a) By adjusting the heating test piece 610 of the fuel system 100, the thermocouple temperature reaches the expected value (high temperature holding temperature) and remains stable.

[0069] b) Adjust the emissivity of the pyrometer to make the temperature of the pyrometer and the temperature of the thermocouple consistent and stable.

[0070] At this point, the current emissivity value is the emissivity of the thermal barrier coating at the high-temperature holding temperature, denoted as K1. Similarly, a hot air gun can be used as a heat source to heat the sample to the target cooling temperature, and the emissivity at the low-temperature cooling point can be adjusted and tested, denoted as K2.

[0071] As a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, in step S3, each cycle of the turbine blade thermal barrier coating fatigue test includes a rapid heating stage, a high temperature holding stage, and a rapid cooling stage, and it is necessary to adjust the rapid heating condition, high temperature holding condition, and rapid cooling condition.

[0072] As mentioned earlier, the temperature curve for turbine blade thermal fatigue testing comprises three stages per cycle: a rapid heating stage, a high-temperature holding stage, and a rapid cooling stage. To ensure the temperature targets and heating / cooling rates required for each of the three stages, at least three different operating conditions must be considered, such as... Figure 7 As shown, the operating conditions are: rapid heating condition A, high temperature holding condition B, and rapid cooling condition C.

[0073] In a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, during high-temperature holding condition debugging, the turbine blade test piece 620 is placed at the gas nozzle 141 position (i.e., Figure 8 (As shown in the hot end position), adjust the emissivity of the pyrometer to the high temperature holding temperature emissivity K1, so that the temperature of the pyrometer reaches the high temperature holding temperature T1 and remains stable, and record the valve position m of the control valve of the first oil circuit 120 of the fuel system 100.

[0074] As a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, when conducting rapid cooling condition debugging, the turbine blade test piece 620 is placed at the gas nozzle 141 position, and the emissivity of the pyrometer is adjusted to the high temperature holding temperature emissivity K1.

[0075] After the pyrometer temperature reaches the high temperature holding temperature T1 and stabilizes, adjust the pyrometer emissivity to the low temperature emissivity K2. At this time, move the turbine blade test piece 620 to the position of the cold air nozzle 710 and blow cold air onto the turbine blade test piece 620. After the pyrometer temperature reaches the low temperature T2, record the cooling rate.

[0076] Based on the cooling rate, repeat the above steps and adjust the cooling air flow until the cooling rate of the turbine blade test piece 620 meets the expected value. At this time, record the cooling air control valve position n% and the cooling time t3 during the rapid cooling phase of the turbine blade test piece 620.

[0077] In a preferred embodiment of the turbine blade thermal fatigue test method of the present invention, during the rapid heating condition debugging, the turbine blade test piece 620 is placed at the position of the cooling gas nozzle 710 (i.e., Figure 9 (As shown in the cold end position), adjust the emissivity of the pyrometer to the high temperature holding emissivity K1; maintain the control valve position m of the first oil circuit 120 of the fuel system 100.

[0078] Run the second oil circuit 130 of the fuel system 100, move the turbine blade test piece 620 to the gas nozzle 141, and when the temperature of the pyrometer reaches the high temperature holding temperature T1, move the turbine blade test piece 620 to the position of the cold gas nozzle 710, and adjust the emissivity of the pyrometer to the low temperature point temperature emissivity K2.

[0079] When the temperature of the pyrometer drops to the low temperature T2, move the turbine blade test piece 620 to the position of the gas nozzle 141, and at the same time adjust the emissivity of the pyrometer to the high temperature holding temperature emissivity K1. When the temperature of the pyrometer rises to the high temperature holding temperature T1, record the heating rate.

[0080] Based on the heating rate, repeat the above steps, adjust the second oil circuit 130 of the fuel system 100 until the heating rate of the turbine blade test piece 620 meets the expected value, and record the valve position w% of the control valve of the second oil circuit 130 of the fuel system 100 and the heating time t1.

[0081] Preferably, the commissioning sequence for the three operating conditions is as follows:

[0082] First, debug the high-temperature holding stage B condition, such as... Figure 8As shown, the turbine blade test piece 620 is positioned at the gas nozzle 141. The pyrometer emissivity is adjusted to the high-temperature holding temperature emissivity K1. According to the dual-oil-circuit dual-nozzle fuel system design of the turbine blade thermal fatigue test device of this invention, the test device operating conditions are adjusted in the first oil circuit 120 until the pyrometer temperature reaches the high-temperature holding temperature T1 and remains stable. At this time, the test device operating condition is the high-temperature holding stage B. The valve position m of the control valve CV201 in the first oil circuit 120 is recorded.

[0083] Next, adjust the rapid cooling phase C and cooling time t3. First, keep the turbine blade test piece 620 at the gas nozzle 141 position and the pyrometer emissivity at the high-temperature holding temperature emissivity K1. The test device is first run in condition B. After the pyrometer temperature reaches the high-temperature holding temperature T1 and stabilizes, adjust the pyrometer emissivity to the cooling low-temperature temperature emissivity K2. At this time, move the turbine blade test piece 620 to the cold gas nozzle 710 position of the test device (e.g., Figure 9 (As shown) A certain amount of cold air is used to cool the test piece. When the temperature of the pyrometer reaches the cooling low temperature point, the cooling rate is recorded. Based on the cooling rate, the above steps are repeated, and the cold air flow rate is adjusted until the cooling rate of the turbine blade test piece 620 meets the expected value. At this time, the valve position n% of the cold air control valve and the cooling time t3 during the rapid cooling phase of the test device are recorded.

[0084] Finally, adjust the heating stage A condition and heating time t1. First, keep the turbine blade test piece 620 at the position of the cold gas nozzle 710 and the pyrometer emissivity at the high temperature holding temperature emissivity K1. According to the dual oil circuit dual nozzle fuel system in the turbine blade thermal fatigue test device of this invention, keep the control valve position of the first oil circuit 120 at m%, and adjust the test device condition and run it through the second oil circuit 130. At this time, move the turbine blade test piece 620 to the gas nozzle 141. When the pyrometer temperature reaches the high temperature holding temperature T1, move the turbine blade test piece 620 to the cold gas nozzle 710. The cold gas flow rate is set according to condition C. At the same time, adjust the pyrometer emissivity to the cooling low temperature point temperature emissivity K2. When the pyrometer temperature drops to the low temperature point temperature T2, move the test piece to the gas nozzle 141. At the same time, adjust the pyrometer emissivity to the high temperature holding temperature emissivity K1 and observe the time it takes for the pyrometer temperature to rise to the high temperature holding temperature, i.e., the heating rate. Based on the heating rate, repeat the above steps, adjust the control valve of the second oil circuit 130 to adjust the working condition of the test device until the heating rate of the turbine blade test piece 620 meets the expected value. At this time, it is the A working condition of the rapid heating stage of the test device. Record the valve position w% of the control valve CV202 and the heating time t1.

[0085] After completing the debugging of each working condition in the test cycle, the working conditions of the test device are set as shown in Table 1 below, and the fatigue test of the thermal barrier coating of the turbine blade can be carried out.

[0086] Table 1 Test Cycle Condition Setting Table

[0087] Operating conditions Turbine blade test specimen position Time (s) pyrometer emissivity First oil circuit switch valve First oil circuit control valve Second oil circuit switch valve Second oil circuit control valve air conditioning control valve air conditioning switch valve A hot end t1 K1 open m% open w% n% close B hot end t2 K1 open m% close w% n% close C cold end t3 K2 open m% close w% n% open

[0088] The actual turbine blade thermal barrier coating fatigue test operating temperature curve is as follows: Figure 10 As shown.

[0089] See Figures 1-10 The present invention also provides a turbine blade thermal fatigue testing device, which is used to perform the turbine blade thermal fatigue testing method as described above. The testing device includes a combustion chamber 140, a fuel system 100, a pyrometer 200, and a test bench 300.

[0090] A gas nozzle 141 is provided on the side of the combustion chamber 140, facing the test bench 300. Gas is ejected through the gas nozzle 141 to heat the turbine blade test piece 620 and / or the test specimen 610.

[0091] The fuel system 100 is connected to the combustion chamber 140 and is used to provide test fuel conditions.

[0092] The pyrometer 200 is connected to the test bench 300 and is used to measure the temperature of the turbine blade test piece 620 and / or the test specimen 610.

[0093] The test bench 300 is provided with an installation structure 400 for mounting turbine blade test pieces 620 and / or test specimens 610.

[0094] The mounting structure 400 may include a test specimen mounting adjustment device 410 for mounting the test specimen 610, and may also include a structure for mounting the turbine blade test piece 620.

[0095] See Figure 8 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the testing device further includes a cooling system, wherein the cooling nozzle 710 of the cooling system is arranged facing the test bench 300, and the cooling system is used to cool the turbine blade test piece 620 and / or test specimen 610.

[0096] The cooling system is designed with cooling nozzles 710 to cool the turbine blade test piece 620 and / or test specimen 610.

[0097] See Figure 2 In a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the fuel system 100 is a dual-oil-circuit dual-nozzle fuel system, including a first oil circuit 120 and a second oil circuit 130, each oil circuit including a supply oil circuit and a return oil circuit.

[0098] One end of the fuel supply circuit is connected to the fuel station, and the other end is connected to the fuel nozzle 110. The fuel nozzle 110 is installed in the combustion chamber 140, and the gas nozzle 141 is installed on one side of the combustion chamber 140. The fuel supply circuit is connected in sequence along the fuel flow direction to the fuel pump (VFP), the flow meter (F), the control valve (CV), the on / off valve (SV), and the check valve (NRV). One end of the return fuel circuit is connected to the fuel pump, and the other end is connected to the fuel station. The return fuel circuit is connected in sequence along the fuel flow direction to the pressure regulating relief valve (PRV) and the cooler (EH).

[0099] The first oil circuit 120 is used to regulate the first gas condition, maintain the oil supply pump frequency and overflow valve pressure constant, and debug the turbine blade test piece 620 in the first gas condition. When the debugging is completed, keep the control valve position of the first oil circuit 120 unchanged, the switch valve is normally open, and the combustion chamber 140 is in normal combustion.

[0100] The second oil circuit 130 adjusts the second gas operating condition by regulating the oil supply. After commissioning, the switching between the first gas operating condition and the second gas operating condition is achieved by switching the switching valve of the first oil circuit 120 and the switching valve of the second oil circuit 130.

[0101] The dual-oil-line dual-nozzle fuel system has two oil lines and two fuel nozzles 110. Each of the first oil line 120 and the second oil line 130 is provided with a fuel nozzle 110. The two fuel nozzles 110 are arranged in the combustion chamber 140. The gas nozzle 141 is arranged on one side of the combustion chamber 140. Gas is sprayed out through the gas nozzle 141 for heating.

[0102] Figure 2 This is a schematic diagram of a dual-fuel-line, dual-nozzle fuel system. As shown in the figure, fuel from the fuel supply lines is supplied to two fuel nozzles 110 in the same combustion chamber 140 via two fuel supply lines. Each fuel supply line contains a fuel pump (VFP), a flow meter (F), a control valve (CV), a switching valve (SV), and a check valve (NRV). Excess fuel in the fuel supply line flows back to the main fuel supply line through a pressure regulating relief valve (PRV) and a cooler (EH).

[0103] Since the two fuel supply lines can be controlled independently, the first fuel line 120 is used to adjust the first operating condition, maintaining a constant fuel pump frequency and overflow valve pressure, and to test the first combustion condition of the test device. Upon completion of the adjustment, the control valve position of the first fuel line 120 remains unchanged, the switching valve is normally open, and combustion occurs normally in the combustion chamber 140. Simultaneously, the second operating condition is adjusted by increasing the fuel supply to the combustion chamber 140 through the second fuel line 130. After completion, the switching of the first and second operating conditions of the test device's combustion chamber is achieved by switching the valves SV202 and SV203.

[0104] Referring to Table 1, as a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, after completing the debugging of the rapid heating condition, the high temperature holding condition, and the rapid cooling condition,

[0105] The emissivity of the pyrometer during the rapid heating phase of the fatigue test cycle of the thermal barrier coating on the turbine blade is set to K1, the switch valve in the first oil circuit 120 is open, the valve position of the control valve in the first oil circuit 120 is m%, the switch valve in the second oil circuit 130 is open, the valve position of the control valve in the second oil circuit 130 is w%, and the cold air switch valve is closed.

[0106] The emissivity of the pyrometer during the high-temperature holding phase of the fatigue test cycle of the turbine blade thermal barrier coating is set to K1, the switch valve in the first oil circuit 120 is open, the valve position of the control valve in the first oil circuit 120 is m%, the switch valve in the second oil circuit 130 is closed, and the cooling gas switch valve is closed.

[0107] The emissivity of the pyrometer during the rapid cooling phase of the fatigue test cycle of the turbine blade thermal barrier coating is set to K2, the switch valve in the first oil circuit 120 is open, the valve position of the control valve in the first oil circuit 120 is m%, the switch valve in the second oil circuit 130 is closed, the cold air switch valve is open, and the valve position of the cold air control valve is n.

[0108] See Figures 3-5 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the mounting structure 400 includes a test specimen mounting and adjusting device 410, and the test bench 300 is also provided with a pyrometer adjusting device 500.

[0109] The test piece mounting and adjusting device 410 is used to fix the test piece 610 and adjust the position and angle of the test piece 610.

[0110] The pyrometer adjustment device 500 is used to adjust the position and temperature measuring angle of the pyrometer 200.

[0111] The pyrometer bracket 510 is mounted on the platform panel through an oblong hole, which allows the position of the pyrometer 200 to be adjusted in the X-axis direction. The spherical adjustment device 520 at the upper end of the pyrometer bracket 510 allows the temperature measurement direction of the pyrometer 200 to be adjusted.

[0112] See Figure 5 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the test specimen mounting and adjusting device 410 includes a test specimen mounting ring 420 and an adjusting platform 430.

[0113] The adjustment platform 430 is movably connected to the test bench 300.

[0114] The test piece mounting ring 420 is fixed on the adjustment platform 430, which can adjust the height, tilt and horizontal position.

[0115] The test specimen 610 is movably connected to the specimen mounting ring 420, and the test specimen 610 can rotate within the specimen mounting ring 420.

[0116] See Figure 5 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the test specimen mounting and adjusting device 410 further includes a test specimen adjusting bolt 440 and a sliding groove 421 on the test specimen mounting ring 420.

[0117] One end of the test piece adjusting bolt 440 is connected to the end of the test piece 610, and the other end of the test piece adjusting bolt 440 is connected to the slide groove 421; by adjusting the connection position of the test piece adjusting bolt 440 in the slide groove 421, the test piece 610 can rotate within the test piece mounting ring 420.

[0118] See Figure 5 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the test specimen mounting and adjusting device 410 further includes a platform adjusting screw 450 and a platform adjusting nut 460.

[0119] The adjustment platform 430 is movably connected to the test bench 300 via the platform adjustment screw 450 and the platform adjustment nut 460. One end of the platform adjustment screw 450 is connected to the test bench 300, and the other end of the platform adjustment screw 450 is connected to the adjustment platform 430.

[0120] The platform adjusting nut 460 is threadedly connected to the platform adjusting screw 450. The platform adjusting nut 460 limits the adjustment platform 430. By adjusting the connection position of the platform adjusting nut 460 on the platform adjusting screw 450, the height and tilt of the adjustment platform 430 can be adjusted.

[0121] See Figure 5 As a preferred embodiment of the turbine blade thermal fatigue testing device of the present invention, the test specimen mounting and adjusting device 410 further includes a slide rail 470 and a slider 480.

[0122] The adjustment platform 430 is movably connected to the test bench 300 via the slide rail 470 and the slider 480. The adjustment platform 430 is connected to the slider 480, and the slider 480 is slidably connected to the slide rail 470.

[0123] When conducting emissivity testing of thermal barrier coatings, the turbine blade thermal fatigue testing device of this invention provides a test gas environment. Since the turbine blade is a curved irregular structure, the measuring point has different positional relationships with the gas and the pyrometer 200 during different blade tests. In order to ensure the consistency of the measurement angle and distance of the measured position during emissivity testing and turbine blade testing, the test piece is adjusted by the emissivity measuring device to make the test position and angle consistent with the real blade, so as to simulate the real test conditions.

[0124] Preferably, it can be achieved through Figure 4 As shown, the consistency adjustment of the emissivity test position can be achieved through structures such as the pyrometer bracket 510, the spherical adjustment device 520, the sample mounting ring 420, the platform adjustment screw 450, and the platform adjustment nut 460.

[0125] Before adjustment, the installed turbine blade test piece 620 is inspected, and the installation angle is measured. Simultaneously, the position and angle of the pyrometer 200 are adjusted using the structure of the pyrometer bracket 510 and the spherical adjustment device 520. Then, the test piece mounting ring 420 is installed, and the angle of the test piece 610 is adjusted using the structure of the test piece mounting ring 420, the platform adjusting screw 450, and the platform adjusting nut 460, ensuring that the angle of the tested position of the test piece 610 matches the measured position of the turbine blade test piece 620.

[0126] Through the above steps, the test conditions of test specimen 610 and turbine blade test piece 620 are finally made consistent.

[0127] like Figure 3 As shown in the figure, the high temperature meter bracket 510 is mounted on the stand panel through an oval hole, which allows the position of the high temperature meter 200 to be adjusted in the X-axis direction. The spherical adjustment device 520 at the upper end of the high temperature meter bracket 510 can adjust the temperature measurement direction of the high temperature meter 200.

[0128] The structural details of the test piece mounting and adjustment device 410 are as follows: Figure 5 As shown, the test specimen 610 is mounted on the specimen mounting ring 420 via the specimen adjusting bolt 440. The specimen mounting ring 420 is mounted on the adjustable platform via a flange. The angle of the test specimen 610 around the z-axis can be adjusted by rotating the specimen adjusting bolt 440, and the angle of the test specimen 610 around the Y-axis can be adjusted by moving the specimen adjusting bolt 440 to the position of the specimen mounting ring 420. The angle of the specimen around the X-axis can be adjusted by adjusting the nut on the adjustable platform 430.

[0129] Preferably, the test specimen 610 is as follows: Figure 6 As shown, the dimensions are 150×20×2mm (length×width×thickness). A thermocouple is pre-embedded at the center of the test specimen 610. The material of the test specimen 610 is the same as that of the turbine blade test piece 620, with a double-sided TBC coating. The plane positions of the pyrometer 200 measuring point and the thermocouple measuring point on the turbine blade test piece 620 are consistent.

[0130] After completing the installation and adjustment of test specimen 610 as described above, the emissivity test of the thermal barrier coating is carried out. The specific method is as follows:

[0131] a) By adjusting the heating test piece 610 of the fuel system 100, the thermocouple temperature reaches the expected value (high temperature holding temperature) and remains stable.

[0132] b) Adjust the emissivity of the pyrometer to make the temperature of the pyrometer and the temperature of the thermocouple consistent and stable.

[0133] At this point, the current emissivity value is the emissivity of the thermal barrier coating at the high-temperature holding temperature, denoted as K1. Similarly, a hot air gun can be used as a heat source to heat the sample to the target cooling temperature, and the emissivity at the low-temperature cooling point can be adjusted and tested, denoted as K2.

[0134] The turbine blade thermal fatigue test method and test apparatus of the present invention have the following beneficial effects:

[0135] I. The dual-oil-circuit dual-nozzle fuel system of the turbine blade thermal fatigue testing device of the present invention enables rapid changes in the gas combustion conditions of the tester by adjusting the fuel quantity through control valves and switching the fuel quantity through on / off valves.

[0136] II. This invention uses a strip-shaped specimen of turbine blade material with thermal barrier coating as the emissivity measurement target. The specimen has a small heat capacity and is surrounded by a flame, so that the temperature and thickness of the specimen center are consistent. By adjusting the angle of the measured point of the specimen with the measured point of the blade through a designed specimen angle adjustment device, the emissivity of the thermal barrier coating of turbine blade in a gas combustion environment can be accurately measured.

[0137] Third, based on the rapid switching of gas operating conditions and the accurate measurement of the emissivity of the thermal barrier coating of turbine blades, this invention designs corresponding debugging methods and can establish test temperature cycle curves as needed.

[0138] In summary, the turbine blade thermal fatigue testing method and apparatus of this invention can achieve rapid switching of burner outlet temperature and accurate measurement of the surface temperature of thermal barrier coating under gas environment conditions. By debugging and establishing the periodic curve of the turbine blade thermal barrier coating thermal fatigue test, the service status of aero-engines in the turbine thermal barrier coating thermal fatigue test is accurately and controllably simulated. This provides a methodological basis and equipment foundation for accurately and quantitatively carrying out coating process assessment tests on engine blades, and assists in the airworthiness certification of aero-engine blade coatings and the establishment of blade coating maintenance and repair recommendations. It also supports the establishment of thermal barrier coating test baselines, research on improving the thermal fatigue resistance of coatings, and the improvement of engine efficiency performance.

[0139] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for testing the thermal fatigue of turbine blades, characterized in that, The experimental method includes the following steps: S1. Install the test specimen and adjust the consistency of the emissivity test position; S2. Heat the test specimen to the set temperature under gas conditions, and adjust the emissivity of the pyrometer to make the pyrometer temperature consistent with the set temperature. S3. Install turbine blade test specimens and conduct fatigue tests on the thermal barrier coating of turbine blades.

2. The turbine blade thermal fatigue test method as described in claim 1, characterized in that, Step S1 includes the following sub-steps: S 11 Adjust the position and measuring angle of the pyrometer; adjust the test position and angle of the test specimen to match the test position and angle of the turbine blade test piece. S 12 Ensure that the material and coating of the test specimen are consistent with those of the turbine blade test piece, and pre-embed a thermocouple in the center of the test specimen to ensure that the thermocouple measuring point corresponds to the pyrometer measuring point.

3. The turbine blade thermal fatigue test method as described in claim 1, characterized in that, Step S2 includes the following sub-steps: S 21 The test specimen is heated by a gas nozzle until the temperature of the thermocouple embedded in the test specimen reaches the high-temperature holding temperature T1; the emissivity of the pyrometer is adjusted so that the temperature of the pyrometer and the temperature of the thermocouple are consistent. At this time, the emissivity of the pyrometer is the high-temperature holding temperature emissivity K1. S 22 1. Heat the test specimen with a hot air gun until the temperature of the thermocouple embedded in the test specimen reaches the low temperature T2; 2. Adjust the emissivity of the pyrometer so that the temperature of the pyrometer and the temperature of the thermocouple are consistent. At this time, the emissivity of the pyrometer is the emissivity K2 of the cooled low temperature.

4. The turbine blade thermal fatigue test method as described in claim 1, characterized in that, In step S3, each cycle of the turbine blade thermal barrier coating fatigue test includes a rapid heating stage, a high-temperature holding stage, and a rapid cooling stage, and adjustments need to be made for the rapid heating condition, the high-temperature holding condition, and the rapid cooling condition.

5. The turbine blade thermal fatigue test method as described in claim 4, characterized in that, During the high-temperature holding condition debugging, the turbine blade test piece is placed at the gas nozzle position, and the emissivity of the pyrometer is adjusted to the high-temperature holding temperature emissivity K1, so that the pyrometer temperature reaches the high-temperature holding temperature T1 and remains stable. The valve position m of the control valve of the first oil circuit of the fuel system is recorded.

6. The turbine blade thermal fatigue test method as described in claim 4, characterized in that, When debugging under rapid cooling conditions, place the turbine blade test piece at the gas nozzle position and adjust the emissivity of the pyrometer to the high-temperature holding temperature emissivity K1; After the pyrometer temperature reaches the high temperature holding temperature T1 and stabilizes, adjust the pyrometer emissivity to the low temperature emissivity K2. At this time, move the turbine blade test piece to the position of the cold air nozzle and blow cold air onto the turbine blade test piece. When the pyrometer temperature reaches the low temperature T2, record the cooling rate. Based on the cooling rate, repeat the above steps and adjust the cooling air flow until the cooling rate of the turbine blade test piece meets the expected value. At this time, record the cooling air control valve position n% and the cooling time t3 during the rapid cooling phase of the turbine blade test piece.

7. The turbine blade thermal fatigue test method as described in claim 4, characterized in that, During rapid temperature rise testing, the turbine blade test piece is placed at the cold air nozzle position, and the pyrometer emissivity is adjusted to the high-temperature holding emissivity K1; the control valve position of the first fuel line is maintained at m%. Run the second oil circuit of the fuel system, move the turbine blade test piece to the gas nozzle, and when the temperature of the pyrometer reaches the high temperature holding temperature T1, move the turbine blade test piece to the cold gas nozzle position and adjust the emissivity of the pyrometer to the low temperature temperature emissivity K2. When the temperature of the pyrometer drops to the low temperature T2, move the turbine blade test piece to the gas nozzle position and adjust the emissivity of the pyrometer to the high temperature holding temperature emissivity K1. When the temperature of the pyrometer rises to the high temperature holding temperature T1, record the heating rate. Based on the heating rate, repeat the above steps, adjust the second oil circuit of the fuel system until the heating rate of the turbine blade test piece meets the expected value, and record the valve position w% of the control valve of the second oil circuit of the fuel system and the heating time t1.

8. A turbine blade thermal fatigue testing device, characterized in that, The test apparatus is used to perform the turbine blade thermal fatigue test method as described in any one of claims 1-7, and the test apparatus includes a combustion chamber, a fuel system, a pyrometer, and a test bench; A gas nozzle is provided on the side of the combustion chamber, and the gas nozzle is positioned facing the test bench. Gas is ejected through the gas nozzle to heat the turbine blade test piece and / or test specimen. The fuel system is connected to the combustion chamber and is used to provide test fuel conditions; The pyrometer is connected to the test bench and is used to measure the temperature of turbine blade test pieces and / or test specimens. The test bench is equipped with an installation structure for mounting turbine blade test pieces and / or test specimens.

9. The turbine blade thermal fatigue testing apparatus as described in claim 8, characterized in that, The test apparatus also includes a cooling system, wherein the cooling nozzles of the cooling system are positioned facing the test bench, and the cooling system is used to cool the turbine blade test piece and / or test specimen.

10. The turbine blade thermal fatigue testing apparatus as described in claim 9, characterized in that, The fuel system is a dual-line dual-injector fuel system, including a first fuel line and a second fuel line, each fuel line including a fuel supply line and a fuel return line; One end of the fuel supply circuit is connected to the fuel station, and the other end is connected to the fuel nozzle. The fuel nozzle is located in the combustion chamber. The fuel supply circuit is connected in sequence along the fuel flow direction to the fuel pump, flow meter, control valve, on / off valve and check valve. One end of the return fuel circuit is connected to the fuel pump, and the other end is connected to the fuel station. The return fuel circuit is connected in sequence along the fuel flow direction to the pressure regulating overflow valve and cooler. The first oil circuit is used to regulate the first gas condition, maintain the oil supply pump frequency and overflow valve pressure constant, and debug the turbine blade test piece to be in the first gas condition. When the debugging is completed, the valve position of the first oil circuit control valve remains unchanged, the switch valve is always open, and the combustion chamber is in normal combustion. The second oil circuit adjusts the second gas operating condition by regulating the oil supply. After commissioning, the switching between the first and second gas operating conditions is achieved by switching the switching valves of the first and second oil circuits.

11. The turbine blade thermal fatigue testing apparatus as described in claim 10, characterized in that, After completing the debugging of rapid heating condition, high temperature holding condition and rapid cooling condition, the emissivity of the pyrometer in the rapid heating stage of the turbine blade thermal barrier coating fatigue test cycle is set to K1, the switch valve in the first oil circuit is open, the valve position of the control valve in the first oil circuit is m%, the switch valve in the second oil circuit is open, the valve position of the control valve in the second oil circuit is w%, and the cold air switch valve is closed. Set the pyrometer emissivity to K1 during the high-temperature holding phase of the turbine blade thermal barrier coating fatigue test cycle, the switch valve in the first oil circuit to be open, the control valve in the first oil circuit to be at position m%, the switch valve in the second oil circuit to be closed, and the cooling gas switch valve to be closed. The emissivity of the pyrometer during the rapid cooling phase of the fatigue test cycle of the turbine blade thermal barrier coating is set to K2, the switch valve in the first oil circuit is open, the valve position of the control valve in the first oil circuit is m%, the switch valve in the second oil circuit is closed, the cold air switch valve is open, and the valve position of the cold air control valve is n.

12. The turbine blade thermal fatigue testing apparatus as described in claim 8, characterized in that, The installation structure includes a test piece installation and adjustment device, and the test bench is also equipped with a pyrometer adjustment device. The test specimen mounting and adjustment device is used to fix the test specimen and adjust its position and angle. The pyrometer adjustment device is used to adjust the position and temperature measurement angle of the pyrometer.

13. The turbine blade thermal fatigue testing apparatus as described in claim 12, characterized in that, The test specimen mounting and adjustment device includes a test specimen mounting ring and an adjustment platform; The adjustment platform is movably connected to the test bench; The test piece mounting ring is fixed on the adjustment platform, which is adjustable in height, tilt, and horizontal position. The test specimen is movably connected to the specimen mounting ring, and the test specimen can rotate within the specimen mounting ring.

14. The turbine blade thermal fatigue testing apparatus as described in claim 13, characterized in that, The test piece mounting and adjusting device also includes a test piece adjusting bolt, and the test piece mounting ring is provided with a sliding groove; One end of the test piece adjusting bolt is connected to the end of the test piece, and the other end of the test piece adjusting bolt is connected to the slide groove; by adjusting the connection position of the test piece adjusting bolt in the slide groove, the test piece can be rotated within the test piece mounting ring.

15. The turbine blade thermal fatigue testing apparatus as described in claim 13, characterized in that, The test specimen mounting and adjustment device also includes a platform adjustment screw and a platform adjustment nut; The adjustment platform is movably connected to the test bench via the platform adjustment screw and the platform adjustment nut. One end of the platform adjustment screw is connected to the test bench, and the other end of the platform adjustment screw is connected to the adjustment platform. The platform adjusting nut is threadedly connected to the platform adjusting screw. The platform adjusting nut limits the position of the adjusting platform. By adjusting the connection position of the platform adjusting nut on the platform adjusting screw, the height and tilt of the adjusting platform can be adjusted.

16. The turbine blade thermal fatigue testing apparatus as described in claim 13, characterized in that, The test specimen mounting and adjustment device also includes a slide rail and a slider; The adjustment platform is movably connected to the test bench via the slide rail and the slider. The adjustment platform is connected to the slider, and the slider is slidably connected to the slide rail.

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