A method and device for testing damping performance of high-temperature damping alloy pipe fittings

Abstract

The application provides a high-temperature damping alloy pipe damping performance test method and device, which comprises a high-temperature gas flow generation system, a high-temperature damping alloy pipe, a vibration acquisition system and a temperature compensation system, wherein the high-temperature damping alloy pipe is fixedly installed on the support platform of the high-temperature gas flow generation system by a rigid support, the gas inlet of the high-temperature damping alloy pipe is aligned with the axis of the gas discharge port of the high-temperature gas flow generation system without direct contact, the vibration sensor in the vibration acquisition system is fixedly installed on the outer wall of the high-temperature damping alloy pipe by a rigid support, and the temperature compensation system is installed on the support platform of the high-temperature gas flow generation system by a rigid support, and the inner cavity of the temperature compensation system wraps the high-temperature damping alloy pipe without direct contact.

Description

Technical Field

[0001] This invention belongs to the field of testing technology for hot-end components of aero-engines or gas turbines, and relates to a method and device for testing the vibration reduction performance of high-temperature damping alloy pipe fittings. Background Technology

[0002] Hot-end pipe components such as the combustion chamber of aero-engines are exposed to high-temperature gas flow environments of 400℃ to 800℃ for extended periods. These components are susceptible to flow-induced vibrations due to excitation from airflow pulsations and combustion oscillations, leading to low-cycle fatigue failure. This is a key factor limiting engine reliability and lifespan. GH3030 nickel-based superalloys are widely used in the manufacture of these components due to their excellent high-temperature strength and oxidation resistance. However, pure GH3030 alloy has limited damping properties and cannot effectively suppress the vibration amplification effect under high-temperature environments.

[0003] High-temperature damping alloys, with their superior damping and vibration reduction performance, are gradually replacing traditional nickel-based alloys in the manufacture of high-temperature pipe components. Accurately evaluating their vibration reduction and noise reduction performance under actual high-temperature conditions is a core basis for material selection and component design. Patent CN120967211A proposes thin-walled high-temperature damping alloy pipe components, their preparation method, and casting system, but does not provide a testing method for their vibration reduction and noise reduction effects. Patent CN103163172B presents a testing method for transient damping of shape memory alloys. This method uses a dynamic mechanical analyzer to heat the alloy sample to its phase transformation temperature range and measures different strain amplitude ranges to test the relationship between the alloy damping value (tanδ) and strain amplitude. This can intuitively reflect the correspondence between the transient term of the alloy damping value and the strain amplitude during the phase transformation process. However, this method cannot determine the high-temperature damping performance of high-temperature damping alloy pipe components.

[0004] Existing vibration testing methods for high-temperature components have significant drawbacks for thin-walled tubular components: Firstly, thin-walled tubular components have low heat capacity and rapid heat dissipation; simply introducing high-temperature combustion gas inside the tube cannot reach the 400–800°C high-temperature testing range, resulting in poor temperature field uniformity and an inability to simulate real high-temperature operating conditions. Secondly, conventional vibration sensors cannot withstand high-temperature environments, making test data susceptible to temperature interference and insufficient accuracy. Furthermore, existing testing methods lack a quantitative comparison scheme for the high-temperature vibration reduction performance of damping alloys versus traditional nickel-based alloys, failing to directly demonstrate the vibration reduction and noise reduction advantages of low-noise damping alloys. In addition, existing vibration reduction performance testing technologies also have the following limitations: 1) Insufficient simulation of operating conditions: Most tests use room temperature static loading, which cannot reproduce the high temperature gas flow and gradient temperature field environment in actual service, resulting in a large deviation between the test results and the actual engineering situation; 2) Single quantitative evaluation dimension: It only focuses on the change of vibration amplitude in one direction, without simultaneously covering key vibration indicators such as peak-to-peak value and root mean square value, and lacks targeted test schemes for different flow channel structures such as straight pipes, bends, and air intake sections. 3) Poor data correlation: The correlation between temperature field and vibration reduction effect has not been established, and it is impossible to assess the influence of high temperature environment on the performance degradation of damping structure. Summary of the Invention

[0005] This application provides a method and apparatus for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, solving the technical problems of insufficient temperature, low testing accuracy, and lack of intuitive performance comparison in the prior art.

[0006] In a first aspect, this application provides a high-temperature damping alloy pipe fitting vibration reduction performance testing device, comprising a high-temperature gas flow generation system (1), a high-temperature damping alloy pipe fitting 6, a vibration acquisition system, and a temperature compensation system 5, wherein: The high-temperature damping alloy pipe fitting 6 is rigidly mounted on the support platform of the high-temperature gas flow generation system (1) with a rigid bracket. The air inlet of the high-temperature damping alloy pipe fitting 6 is aligned with the axis of the gas discharge port of the high-temperature gas flow generation system (1) but there is no direct contact. The vibration sensor in the vibration acquisition system is rigidly mounted on the outer wall of the high-temperature damping alloy pipe fitting 6 with a rigid bracket. The temperature compensation system 5 is rigidly mounted on the support platform of the high-temperature gas flow generation system (1). The inner cavity of the temperature compensation system 5 wraps the high-temperature damping alloy pipe fitting 6 but there is no direct contact.

[0007] Secondly, this application provides a method for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, including: Step 1: Prepare two sets of test pipe fittings of the same specifications, including high-temperature damping alloy pipe fittings and nickel-based high-temperature alloy pipe fittings. One set is the control group and the other is the test group. Install the two sets of test pieces in the vibration reduction performance testing device of high-temperature damping alloy pipe fittings in Example 1 and carry out vibration reduction performance testing. Arrange one high-temperature acceleration sensor in each of the X / Y / Z directions of the straight pipe section, the bend section and the air inlet section, and at the same time arrange thermocouples on the outer wall of the pipe fittings to collect temperature data. Step 2: Start the resistance furnace for heating and the high-temperature gas flow simulation system, adjust the gas temperature and flow rate to make the average temperature of the test pipe reach the target working condition, and keep it heated until the temperature field of the test pipe stabilizes. Step 3: After the operating conditions stabilize, synchronously collect the peak-to-peak vibration values ​​at each measuring point in the control group using the vibration acquisition system. Root mean square value Peak-to-peak vibration values ​​at each measuring point in the test group Root mean square value At the same time, the temperature data of each measuring point is recorded; Step 4: According to , , and Calculate the vibration reduction amplitude at each measuring point; combine the temperature data under different working conditions to establish a temperature-vibration reduction amplitude correlation curve and evaluate the vibration reduction performance variation law of the test pipe fitting; Step 5: Adjust the gas flow temperature and flow rate, repeat steps 2 to 4, and complete the test at multiple operating points within the 400℃~800℃ range to comprehensively evaluate the vibration reduction performance variation under different temperatures.

[0008] In summary, this invention proposes a method and apparatus for testing the vibration reduction performance of high-temperature damping alloy tubular components. By combining the flow of high-temperature gas inside the tube with zoned heating in an external resistance furnace, a high-temperature environment of 400–800°C is accurately constructed for thin-walled tubular components. A high-temperature resistant vibration sensor is used to collect vibration signals, and the vibration reduction performance of high-temperature damping alloys and nickel-based high-temperature alloys is quantitatively compared. This invention solves the problems of insufficient temperature for existing high-temperature vibration tests, unrealistic simulation of operating conditions, single evaluation dimensions, and poor data correlation. It enables comprehensive and accurate testing of the vibration reduction effect of high-temperature damping structures under actual service conditions, providing reliable experimental data support for the design optimization of vibration reduction structures for high-temperature tubular components in aero-engines. Attached Figure Description

[0009] Figure 1 Schematic diagram of a high-temperature damping alloy pipe fitting vibration reduction performance testing device.

[0010] Figure 2 Schematic diagram of the testing locations for high-temperature damping alloy pipe fittings and vibration reduction performance. Detailed Implementation

[0011] This invention provides a method and apparatus for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, which can achieve accurate quantitative evaluation of the vibration reduction effect of high-temperature pipe fitting structures under multiple working conditions and multiple vibration directions, and provide experimental basis for the fatigue resistance design of aero-engine exhaust pipe fittings.

[0012] Example 1 like Figure 1 As shown, the present invention provides a high-temperature damping alloy pipe fitting vibration reduction performance testing device, comprising a high-temperature gas flow generation system (1), a high-temperature damping alloy pipe fitting 6, a vibration acquisition system, and a temperature compensation system 5, wherein: The arrows in the figure indicate the direction of high-temperature gas flow during the test. The high-temperature damping alloy pipe 6 is rigidly mounted on the support platform of the high-temperature gas flow generation system (1). The air inlet of the high-temperature damping alloy pipe 6 is aligned with the axis of the gas outlet of the high-temperature gas flow generation system (1) but there is no direct contact. The vibration sensor in the vibration acquisition system is rigidly mounted on the outer wall of the high-temperature damping alloy pipe 6. The temperature compensation system 5 is rigidly mounted on the support platform of the high-temperature gas flow generation system (1). The inner cavity of the temperature compensation system 5 encloses the high-temperature damping alloy pipe 6 but there is no direct contact.

[0013] Specifically, the high-temperature gas flow generation system (1) includes a gas generator 2, a flow regulating valve 3, and a guide section 4. The gas generator is fixedly mounted on a support frame by bolts; the flow regulating valve 3 is connected to the gas outlet end of the gas generator 2 by threads, which can adjust the gas discharge flow rate; the guide section 4 is welded to the outlet end of the flow regulating valve 3, which can guide the high-temperature gas into the high-temperature damping alloy pipe fitting 6. The high-temperature gas flow generation system can provide a high-temperature gas flow with a temperature of 400℃~800℃ and an adjustable flow rate, replicating the actual flow field environment of the engine exhaust pipe.

[0014] Specifically, such as Figure 2 As shown, the high-temperature damping alloy pipe fitting 6 includes three flow channel structures: a straight pipe section, a bend in the pipe section, and an air inlet section. Figure 2 The direction of the middle arrow indicates the flow direction of the high-temperature gas. The high-temperature gas flows in from the inlet section, flows through the bend section, and then flows out from the straight section. The base material is a high-temperature damping alloy, while the control group is a nickel-based high-temperature alloy material pipe fitting.

[0015] Specifically, the vibration acquisition system includes three piezoelectric high-temperature accelerometers, respectively arranged in the X / Y / Z vibration directions of the intake section, bend section, and straight section. The vibration test points are as follows: Figure 2 At points I, II, and III shown, peak-to-peak and root mean square (RMS) values ​​of vibration were collected simultaneously at each vibration test point.

[0016] Specifically, the temperature compensation system 5 includes a temperature compensation resistance furnace, pipe wall thermocouples, and gas flow thermocouples. The temperature compensation resistance furnace is rigidly mounted on a support frame. The inner cavity of the furnace encloses the high-temperature damping alloy pipe fitting but is not in direct contact with it. The pipe wall thermocouples are attached to the outer wall of the high-temperature damping alloy pipe fitting with high-temperature resistant adhesive. The gas flow thermocouples are attached to the inner walls of the exhaust pipe inlet and outlet ends with high-temperature resistant adhesive. These are used to collect the average temperature of the pipe fitting and the local temperature at the vibration measurement point in real time, establishing the correlation between the temperature field and the vibration reduction performance. The high-temperature gas delivery system is started, and high-temperature gas at a preset temperature is introduced into the inner wall of the high-temperature damping alloy pipe fitting. At the same time, the segmented resistance furnace on the outer wall is turned on for temperature compensation heating. The temperature data is fed back in real time through the thermocouples, and the heating power of the resistance furnace and the gas flow rate are adjusted to accurately control the temperature of the high-temperature damping alloy pipe fitting within the range of 400-800℃. The temperature is maintained for 30-60 minutes to ensure that the overall temperature of the high-temperature damping alloy pipe fitting is uniform and stable, eliminating the interference of temperature gradient on the test results.

[0017] Specifically, the data acquisition and analysis unit synchronously receives vibration and temperature data, calculates the vibration reduction at each measuring point, and generates a vibration reduction performance evaluation report.

[0018] Specifically, the test involves the fabrication of tubing, including high-temperature damping alloy tubing and nickel-based high-temperature alloy tubing. High-temperature damping alloy tubing and nickel-based high-temperature alloy tubing were machined separately. The diameter, wall thickness, and length of the two sets of test tubing were completely identical to ensure a single variable in the testing conditions. Burrs and oxide scale were removed from the sample surfaces to ensure consistent surface flatness. The chemical composition of the high-temperature damping alloy tubing was Cu:13. 17wt.%; Ni: 8 15 wt.%; Fe: 2 6 wt.%; Zn: 3 9 wt.%; Al: 0.5 3 wt.%; balance is Mn and other unavoidable impurities; the chemical composition of nickel-based high-temperature alloy pipe fittings is GH3030 alloy: Cr: 19-22 wt.%, Ti: 0.15-0.35 wt.%, Fe≤1.5 wt.%, Mn≤0.5 wt.%, Si≤0.8 wt.%, Cu≤0.2 wt.%, Al≤0.15 wt.%, balance is Ni and other unavoidable impurities.

[0019] Example 2 This invention provides a method for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, comprising: Step 1: Prepare two sets of test pipe fittings of the same specifications, including a high-temperature damping alloy pipe fitting and a nickel-based high-temperature alloy pipe fitting. One set serves as the control group, and the other as the test group. Install the two sets of specimens into the vibration reduction performance testing device for high-temperature damping alloy pipe fittings in Example 1, and conduct vibration reduction performance tests. Place one high-temperature accelerometer in each of the X / Y / Z directions of the straight pipe section, the bend section, and the air inlet section. Simultaneously, place thermocouples on the outer wall of the pipe fittings to collect temperature data. One control group can be pure GH3030 nickel-based high-temperature alloy pipe fittings, and the other test group can be high-temperature damping alloy pipe fittings.

[0020] Step 2: Start the resistance furnace for heating and the high-temperature gas flow simulation system, adjust the gas temperature and flow rate to make the average temperature of the test pipe reach the target working condition, and keep it heated until the temperature field of the test pipe stabilizes. The target operating conditions include 550℃, 600℃, and 650℃.

[0021] Step 3: After the operating conditions stabilize, synchronously collect the peak-to-peak vibration values ​​at each measuring point in the control group using the vibration acquisition system. Root mean square value Peak-to-peak vibration values ​​at each measuring point in the test group Root mean square value At the same time, the temperature data of each measuring point is recorded; In practical applications, each working condition is collected three times, and the average value is taken as the valid data for that working condition.

[0022] Step 4: According to , , and Calculate the vibration reduction amplitude at each measuring point; combine the temperature data under different working conditions to establish a temperature-vibration reduction amplitude correlation curve and evaluate the vibration reduction performance variation law of the test pipe fitting; Specifically, step 4 includes: Calculate the vibration reduction at each measuring point using the following formula: Peak-to-peak value reduction:

[0023] The decrease in root mean square value: .

[0024] Step 5: Adjust the gas flow temperature and flow rate, repeat steps 2 to 4, and complete the test at multiple operating points within the 400℃~800℃ range to comprehensively evaluate the vibration reduction performance variation under different temperatures.

[0025] In summary, the present invention provides a method and apparatus for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, which has the following beneficial effects: ① Realistic operating condition simulation: Through the high-temperature gas flow simulation system, the high temperature and airflow pulsation environment of the actual service of the exhaust pipe of the aircraft engine is reproduced, which solves the problem of large deviation between the room temperature test and the actual engineering. ②Comprehensive evaluation dimensions: Simultaneously collects vibration peak-to-peak value, root mean square value and temperature data to achieve multi-index, multi-condition and multi-directional quantitative evaluation of vibration reduction performance, with high data reliability; ③ Strong adaptability: It can be adapted to various typical flow channel structures such as straight pipe sections, bent pipe sections, and air inlet sections, providing targeted test solutions for vibration reduction design of high-temperature pipe fittings with different structural forms; ④ High engineering application value: The test results can be directly used to verify the vibration reduction effect of high temperature damping structures, and provide key test data support for the fatigue design, life assessment and optimization of hot end pipes of aero engines.

[0026] Example 3 Specifically, the test tube fabrication includes high-temperature damping alloy tubes and high-temperature damping alloy tubes. High-temperature damping alloy tubing and nickel-based high-temperature alloy tubing were machined separately. The diameter, wall thickness, and length of the two sets of test tubing were completely identical to ensure a single variable in the testing conditions. Burrs and oxide scale were removed from the sample surfaces to ensure consistent surface flatness. The chemical composition of the high-temperature damping alloy material was: Cu: 13 wt.%; Ni: 8 wt.%; Fe: 2 wt.%; Zn: 3 wt.%; Al: 0.5 wt.%; the balance being Mn and other unavoidable impurities. The chemical composition of the nickel-based high-temperature alloy material was: Cr: 20.5 wt.%; Ti: 0.25 wt.%; the balance being Ni and other unavoidable impurities. The tubing was machined to the required diameter... Sample of a thin-walled pipe fitting with a diameter of 108 mm and a wall thickness of 2 mm is attached. Figure 1 The arrow indicates the high-temperature gas inlet end. The dimensional tolerance of the two sets of samples is controlled within ±0.05mm. The surface oxide layer is removed by grinding to ensure consistent surface roughness.

[0027] 1) Test conditions and specimen parameters In this embodiment, the pipe fittings in the test group are high-temperature damping alloy pipe fittings, and the control group are nickel-based high-temperature alloy pipe fittings; the test conditions are divided into 3 groups, corresponding to the straight pipe section (average temperature 626 / 615℃, vibration point temperature 676 / 670℃), the bend pipe section (average temperature 602 / 608℃, vibration point temperature 604 / 611℃), and the air inlet section (average temperature 550 / 555℃, vibration point temperature 474 / 480℃).

[0028] 2) Test Results and Analysis The test data is shown in the table below:

[0029] 3) Vibration reduction performance analysis ① High-temperature environment adaptability: Under a wide temperature range of 474℃~676℃, the peak-to-peak value and root mean square value of vibration of the test group pipe fittings were significantly reduced. Among them, the straight pipe section, the bend section and the air inlet section had the best vibration reduction effect in the X direction, with the peak-to-peak value reduction exceeding 60% and the root mean square value reduction reaching the highest of 67.2%. ② Multi-channel structure adaptability: For three typical flow channel structures, namely straight pipe section, bend pipe section and air inlet section, high temperature damping alloy pipe fittings all show stable vibration reduction effect, effectively suppressing the vibration amplification effect caused by the sudden change of flow field in bend pipe and air inlet disturbance. ③ Vibration direction sensitivity: The vibration reduction effect is best in the X direction (airflow direction), and the reduction is generally higher than that in the Y / Z direction. This indicates that the damping structure has a more significant effect on suppressing the airflow-induced vibration of the pipe, which is consistent with the main excitation characteristics of the vibration of the aero-engine pipe.

Claims

1. A device for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, characterized in that, Includes a high-temperature gas flow generation system (1), a high-temperature damping alloy pipe fitting (6), a vibration acquisition system, and a temperature compensation system (5), wherein: The high-temperature damping alloy pipe fitting (6) is fixedly mounted on the support platform of the high-temperature gas flow generation system (1) with a rigid bracket. The air inlet of the high-temperature damping alloy pipe fitting (6) is aligned with the axis of the gas discharge port of the high-temperature gas flow generation system (1) but there is no direct contact. The vibration sensor in the vibration acquisition system is fixedly mounted on the outer wall of the high-temperature damping alloy pipe fitting (6) with a rigid bracket. The temperature compensation system (5) is mounted on the support platform of the high-temperature gas flow generation system (1) with a rigid bracket. The inner cavity of the temperature compensation system (5) wraps the high-temperature damping alloy pipe fitting (6) but there is no direct contact.

2. The apparatus according to claim 1, characterized in that, The high-temperature gas flow generation system (1) includes a gas generator (2), a flow regulating valve (3) and a guide section (4); the gas generator is fixedly installed on the support frame by bolts; the flow regulating valve (3) is connected to the gas outlet end of the gas generator (2) by threads to regulate the gas discharge flow; the guide section (4) is welded to the outlet end of the flow regulating valve (3) to introduce the high-temperature gas into the high-temperature damping alloy pipe fitting (6).

3. The apparatus according to claim 1, characterized in that, The high-temperature damping alloy pipe fitting (6) includes three flow channel structures: straight pipe section, bend pipe section, and inlet section. High-temperature gas flows in from the inlet section, flows through the bend pipe section, and then flows out from the straight pipe section. The base material is a high-temperature damping alloy, while the control group is a nickel-based high-temperature alloy pipe fitting.

4. The apparatus according to claim 3, characterized in that, The vibration acquisition system includes three piezoelectric high-temperature accelerometers, which are respectively arranged in the X / Y / Z vibration directions of the air intake section, the bend section, and the straight section, and simultaneously collect the peak-to-peak value and root mean square value data of each vibration test point.

5. The apparatus according to claim 1, characterized in that, The temperature compensation system (5) includes a heating resistance furnace, a pipe wall thermocouple, and a gas flow thermocouple. The heating resistance furnace is fixedly installed on a support frame with a rigid bracket. The inner cavity of the heating resistance furnace is wrapped with a high-temperature damping alloy pipe but there is no direct contact. The pipe wall thermocouple is pasted to the outer wall of the high-temperature damping alloy pipe with high-temperature resistant adhesive. The gas flow thermocouple is pasted to the inner wall of the inlet and outlet of the exhaust pipe with high-temperature resistant adhesive. It is used to collect the average temperature of the pipe and the local temperature of the vibration measurement point in real time, and to establish the correlation between the temperature field and the vibration reduction performance.

6. The apparatus according to claim 1, characterized in that, Start the high-temperature gas flow generation system (1), introduce high-temperature gas at a preset temperature into the inner wall of the high-temperature damping alloy pipe, and at the same time turn on the external wall segmented resistance furnace for supplementary heating. The temperature data is fed back in real time through thermocouples, and the heating power and gas flow of the resistance furnace are adjusted to control the temperature of the high-temperature damping alloy pipe within the range of 400 to 800℃. The temperature is maintained for 30 to 60 minutes to ensure that the overall temperature of the high-temperature damping alloy pipe is uniform and stable, and to eliminate the interference of temperature gradient on the test results.

7. A method for testing the vibration reduction performance of high-temperature damping alloy pipe fittings, characterized in that, include: Step 1: Prepare two sets of test pipe fittings of the same specifications, including high-temperature damping alloy pipe fittings and nickel-based high-temperature alloy pipe fittings. One set is the control group and the other is the test group. Install the two sets of test pieces in the vibration reduction performance testing device of high-temperature damping alloy pipe fittings in Example 1 and carry out vibration reduction performance testing. Arrange one high-temperature acceleration sensor in each of the X / Y / Z directions of the straight pipe section, the bend section and the air inlet section, and at the same time arrange thermocouples on the outer wall of the pipe fittings to collect temperature data. Step 2: Start the resistance furnace for heating and the high-temperature gas flow simulation system, adjust the gas temperature and flow rate to make the average temperature of the test pipe reach the target working condition, and keep it heated until the temperature field of the test pipe stabilizes. Step 3: After the operating conditions stabilize, synchronously collect the peak-to-peak vibration values ​​at each measuring point in the control group using the vibration acquisition system. Root mean square value Peak-to-peak vibration values ​​at each measuring point in the test group Root mean square value At the same time, the temperature data of each measuring point is recorded; Step 4: According to , , and Calculate the vibration reduction amplitude at each measuring point; combine the temperature data under different working conditions to establish a temperature-vibration reduction amplitude correlation curve and evaluate the vibration reduction performance variation law of the test pipe fitting; Step 5: Adjust the gas flow temperature and flow rate, repeat steps 2 to 4, and complete the test at multiple operating points within the 400℃~800℃ range to comprehensively evaluate the vibration reduction performance variation under different temperatures.

8. The method according to claim 7, characterized in that, Specifically, step 4 includes: Calculate the vibration reduction at each measuring point using the following formula: Peak-to-peak value reduction: The decrease in root mean square value: .

Images