Thermoacoustic vibration coupled box section structure test device and test method

Abstract

The invention belongs to the technical field of airplane strength design, and particularly relates to a thermoacoustic vibration coupled box section structure test device and test method. The test device comprises a vibration sliding table, a traveling wave tube, a quartz lamp heater, a mouth frame type switching section and a test clamp, the test clamp is fixed on the vibration sliding table and vibrates along with the vibration of the vibration sliding table, and the mouth frame type switching section is fixed on the test clamp and is used for fixing a test piece; the traveling wave tube is of a square box structure with one side open, the test piece is supported by the vibration sliding table and the test clamp and extends into the square box structure from the open end, and the quartz lamp heater is arranged on the inner side of a cover plate at the closed end of the square box structure. Accurate control and combined loading of heat, noise and vibration loads are realized, so that the actual loaded environment during high-speed flight of the aircraft is simulated, and the loading test result of the test piece is more accurate.

Description

Technical Field

[0001] This application belongs to the field of aircraft strength design technology, specifically relating to a test device and test method for a thermoacoustic-vibration coupled box-section structure. Background Technology

[0002] Hypersonic vehicles are entering a fast track of development. With continuous improvements in flight speed, repeatability, and effective range, research on the integrity and reliability of the vehicle structure is becoming increasingly important. The load environment in the nozzle region of a hypersonic vehicle is complex and harsh, exhibiting characteristics such as high temperature, strong noise, and severe vibration, which can easily induce structural fatigue cracks. This poses a significant challenge to the strength assessment and verification of integrated load-bearing / functional structures with shielding functions. When verifying the strength of integrated load-bearing / functional structures, if loading is performed entirely according to the actual load field, it requires ground-based engine operation, which is extremely costly and even difficult to implement.

[0003] Ground-based verification tests are a crucial means and approach for evaluating and validating the structural performance of hypersonic vehicles, and are an important component of structural reliability. Strength verification in a laboratory environment requires consideration of the combined loading design methods for thermal, acoustic, and vibrational loads, as well as the equivalent simulation of dynamic boundary conditions. The core challenge of this research lies in how to reasonably simulate complex load fields, especially accurately reproducing structural damage.

[0004] When designing experiments for integrated load-bearing / functional structures in the laboratory, they are generally simplified into box-section structures. Currently, experiments on box-section structures under thermo-acoustic-vibration coupling environments are limited by experimental loading methods. Most experiments are conducted using a single load loading method, which makes it difficult to truly reproduce the multi-factor coupled load environment of an aircraft during high-speed flight. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a test apparatus and method for thermoacoustic-vibration coupled box-section structures.

[0006] The first aspect of this application provides a test device for a box-section structure with thermo-acoustic-vibration coupling, which mainly includes: a vibration slide, a traveling wave tube, a quartz lamp heater, a frame-type transition section, and a test fixture;

[0007] The test fixture is fixed to the vibration slide and vibrates with the vibration slide. The frame-type transition section is fixed to the test fixture and is used to fix the test piece.

[0008] The traveling wave tube is a square box structure with one open side. The test piece is supported by a vibration slide and test fixture and extends into the square box structure from the open end. The quartz lamp heater is arranged inside the closed end cover plate of the square box structure.

[0009] Preferably, an accelerometer is attached to the vibration slide to measure the applied vibration load, so as to cooperate with the vibration testing machine to achieve closed-loop control of the vibration load spectrum.

[0010] Preferably, a high-temperature probe sensor is arranged above the box structure of the traveling wave tube to receive noise within the box structure, so as to cooperate with the noise controller to achieve closed-loop control of the noise load spectrum.

[0011] Preferably, the high-temperature probe sensor is wrapped with a PVC hose, and the PVC hose is connected to the water cooling system.

[0012] Preferably, the quartz lamp heater includes a lamp holder and two rows of quartz lamp heating elements arranged on the lamp holder, the two rows of quartz lamp heating elements are arranged alternately, and the lamp holder has a hollow pipe connected to a water cooling system.

[0013] Preferably, a groove is provided in the middle of the upper part of the frame-shaped transition section to accommodate the reinforcing rib of the test piece, and the width of the groove is not less than the width of the reinforcing rib of the test piece.

[0014] Preferably, the bottom surface of the test fixture connected to the vibration slide is provided with a rectangular pipe, which is connected to a water cooling system.

[0015] The second aspect of this application provides a thermo-acoustic-vibration coupled test method for box-section structures, which uses the thermo-acoustic-vibration coupled test device described above to conduct tests on box-section structures in river sections. The method includes:

[0016] The noise test system, heating test system and vibration test system were debugged separately, including adjusting the power and phase of each loudspeaker of the traveling wave tube according to the noise load spectrum of the test, recording the controller output voltage value of the quartz lamp heater according to the target heating temperature requirement, and determining that the vibration slide meets the test requirements of the load level specified in the loading test.

[0017] To conduct the formal test, the quartz lamp heater first provides the heating load. After reaching the target temperature, the temperature is maintained for a set time. Then, the traveling wave tube applies the noise load to the target acoustic load spectrum. Finally, the vibration slide table applies the vibration load to the target value, and the test data is recorded.

[0018] Preferably, the controller output voltage value for recording the quartz lamp heater includes:

[0019] The test piece is heated to the target heating temperature using a quartz lamp heater and held for 10 minutes. The output voltage value at this time is then recorded as the controller output voltage value. If the fluctuation rate of this voltage value exceeds the set value, the average value of all data within 30 seconds is recorded as the controller output voltage value.

[0020] This application achieves precise control and combined loading of thermal, noise, and vibration loads, thereby simulating the actual load environment of an aircraft during high-speed flight, making the loading test results of the test specimen more accurate. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of a preferred embodiment of the thermoacoustic-vibration coupling test device for box-section structures in this application.

[0022] Figure 2 This application Figure 1 The internal structure diagram of the traveling wave tube in the embodiment shown.

[0023] Among them, 1-vibration slide, 2-traveling wave tube, 3-high temperature probe microphone, 4-quartz lamp heater, 5-frame-type adapter section, 6-test fixture, 7-rectangular pipeline, 8-groove. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are only some, not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0025] The first aspect of this application provides a test device for a box-section structure with thermoacoustic-vibration coupling, such as... Figures 1-2 As shown, it mainly includes: a vibration slide table 1, a traveling wave tube 2, a quartz lamp heater 4, a frame-type transition section 5, and a test fixture 6;

[0026] The test fixture 6 is fixed to the vibration slide table 1 and vibrates with the vibration of the vibration slide table 1. The frame-type transition section 5 is fixed on the test fixture 6 and is used to fix the test piece.

[0027] The traveling wave tube 2 is a square box structure with one side open. The test piece is supported by the vibration slide table 1 and the test fixture 6 and extends into the square box structure from the open end. The quartz lamp heater 4 is arranged inside the closed end cover plate of the square box structure.

[0028] This application provides vibration load through vibration slide 1, noise load through traveling wave tube 2, and thermal load through quartz lamp heater 4 to achieve a combined thermal-acoustic-vibration loading test, thereby simulating the actual load environment of an aircraft during high-speed flight.

[0029] In some alternative embodiments, an accelerometer is attached to the vibration slide 1 to measure the applied vibration load, so as to cooperate with the vibration testing machine to achieve closed-loop control of the vibration load spectrum.

[0030] In some alternative embodiments, a high-temperature probe sensor 3 is arranged above the box structure of the traveling wave tube 2 to receive noise within the box structure, so as to cooperate with the noise controller to achieve closed-loop control of the noise load spectrum.

[0031] The above method achieves closed-loop loading of vibration load and noise load.

[0032] In some alternative embodiments, the high-temperature probe sensor 3 is wrapped with a PVC hose, which is connected to a water cooling system.

[0033] This embodiment connects a PVC hose to a water pump to form a miniature water-cooling system, which provides temperature protection for the high-temperature probe microphone.

[0034] In some alternative embodiments, the quartz lamp heater 4 includes a lamp holder and two rows of quartz lamp heating elements arranged on the lamp holder, the two rows of quartz lamp heating elements being arranged alternately, and the lamp holder having a hollow pipe connected to a water cooling system.

[0035] In addition, bolt holes are designed at the lamp holder protrusion to install the pressure plate by bolts, preventing the lamp tube from falling off during the test.

[0036] In some alternative embodiments, a groove is provided in the middle of the upper part of the frame-shaped transition section 5 to accommodate the reinforcing rib of the test piece, and the width of the groove is not less than the width of the reinforcing rib of the test piece.

[0037] In this embodiment, a frame-type transition section is designed between the box segment structure fixture and the test piece mounting location to facilitate installation and testing.

[0038] In some alternative embodiments, the bottom surface of the test fixture 6, which is connected to the vibration slide, is provided with a rectangular pipe 7, which is connected to a water cooling system.

[0039] In this embodiment, the main structure of the test fixture 6 is welded from 30×30 hollow square steel. Before the test, modal analysis and strength verification of the fixture are performed using finite element software. The bottom surface of the test fixture 6, which connects to the vibration slide, is connected to a rectangular pipe 7 welded from hollow square steel. This pipe is used to connect inlet and outlet water to cool the fixture and protect the vibration slide. The test fixture is bolted to the frame-type transition section for easy disassembly of the test piece.

[0040] The second aspect of this application provides a thermo-acoustic-vibration coupled test method for box-section structures, which uses the thermo-acoustic-vibration coupled test device described above to conduct tests on box-section structures in river sections. The method includes:

[0041] The noise test system, heating test system and vibration test system were debugged separately, including adjusting the power and phase of each loudspeaker of the traveling wave tube 2 according to the noise load spectrum of the test, recording the output voltage value of the controller of the quartz lamp heater 4 according to the target heating temperature requirement, and determining that the vibration slide table 1 meets the test requirements of the load level specified in the loading test.

[0042] To conduct the formal test, the quartz lamp heater 4 first provides the heating load. After reaching the target temperature, the temperature is maintained for a set time. Then, the traveling wave tube applies the noise load to the target acoustic load spectrum. Finally, the vibration slide 1 applies the vibration load to the target value, and the test data is recorded.

[0043] In this embodiment, after the test device is installed, the water cooling system, noise test system, heating test system, and vibration test system are debugged in sequence. Only after the debugging is completed can the formal test be carried out.

[0044] For the commissioning of the water cooling system, the test device is installed according to the design, and the water cooling valves are turned on to check whether each water cooling system is normal.

[0045] For the commissioning of the noise test system, the probe microphones are calibrated on-site to ensure that the test loading control system is powered on normally. The loudspeakers are turned on, and the power and phase of each loudspeaker are adjusted according to the test target spectrum until the test requirements are met.

[0046] For the debugging of the heating test system, thermocouples are welded and pasted on the surface of the test piece according to the test requirements. The thermocouples are connected to the temperature measurement and control system, the thyristor is turned on, the temperature is heated to the target temperature, and the output voltage value of the controller of the quartz lamp heater 4 is recorded.

[0047] In some alternative implementations, recording the controller output voltage value of the quartz lamp heater 4 includes:

[0048] The test piece is heated to the target heating temperature by a quartz lamp heater 4 and held for 10 minutes. The output voltage value at this time is then recorded as the controller output voltage value. If the fluctuation rate of this voltage value exceeds the set value, the average value of all data within 30 seconds is recorded as the controller output voltage value.

[0049] For the commissioning of the vibration test system, turn on the vibration table, connect the vibration measurement link, install the test fixtures and test specimens, apply the load specified for the test, and confirm that the measurement link is correct and that the vibration table's loading capacity meets the test requirements.

[0050] The next step is the formal test. During the test, the frame-type adapter section connected to the test fixture is pushed into the traveling wave tube, so that the outer surface of the test piece is flush with the inner wall of the traveling wave tube, completely immersed in the noise field. The frame-type fixture must be designed to be 5mm smaller than the perimeter of the traveling wave tube opening. Next, a thermal load is applied, heating the specimen to the target temperature and holding it thereafter. Then, a noise load is applied. The resonant frequency of the test piece is measured using a small-scale broadband noise test. After the resonant frequency is measured, noise is applied according to the target spectrum. Once the noise load stabilizes, data is recorded for 30 seconds. Finally, a vibration load is applied, using an accelerometer on a horizontal slide for feedback. Once the target spectrum is reached, data is also recorded for 30 seconds.

[0051] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A test device for a box-section structure with thermoacoustic-vibration coupling, characterized in that, include: Vibration slide (1), traveling wave tube (2), quartz lamp heater (4), frame-type transition section (5) and test fixture (6); The test fixture (6) is fixed on the vibration slide (1) and vibrates with the vibration of the vibration slide (1). The frame-type transition section (5) is fixed on the test fixture (6) and used to fix the test piece. The traveling wave tube (2) is a square box structure with one side open. The test piece is supported by the vibration slide (1) and the test fixture (6) and extends into the square box structure from the open end. The quartz lamp heater (4) is arranged inside the closed end cover plate of the square box structure.

2. The thermoacoustic-vibration coupled box-section structure test device according to claim 1, characterized in that, An accelerometer is attached to the vibration slide (1) to measure the applied vibration load, so as to cooperate with the vibration testing machine to realize closed-loop control of the vibration load spectrum.

3. The thermoacoustic-vibration coupled box-section structure test device according to claim 1, characterized in that, A high-temperature probe sensor (3) is arranged above the box structure of the traveling wave tube (2) to receive noise inside the box structure, so as to cooperate with the noise controller to realize closed-loop control of the noise load spectrum.

4. The thermoacoustic-vibration coupled box-section structure test device according to claim 3, characterized in that, The high-temperature probe sensor (3) is wrapped with a PVC hose, which is connected to the water cooling system.

5. The test device for thermoacoustic-vibration coupling of a box-section structure according to claim 1, characterized in that, The quartz lamp heater (4) includes a lamp holder and two rows of quartz lamp heating elements arranged on the lamp holder. The two rows of quartz lamp heating elements are arranged alternately, and the lamp holder has a hollow pipe connected to a water cooling system.

6. The test device for thermoacoustic-vibration coupling of a box-section structure according to claim 1, characterized in that, The upper middle of the frame-type transition section (5) has a groove for accommodating the reinforcing rib of the test piece, and the width of the groove is not less than the width of the reinforcing rib of the test piece.

7. The test device for thermoacoustic-vibration coupling of a box-section structure according to claim 1, characterized in that, The bottom surface of the test fixture (6) connected to the vibration slide is provided with a rectangular pipe (7), which is connected to the water cooling system.

8. A test method for a box-section structure with thermoacoustic-vibration coupling, characterized in that, The method for conducting river section box structure tests using the thermoacoustic-vibration coupled box structure test apparatus as described in claim 1 includes: The noise test system, heating test system and vibration test system were debugged respectively, including adjusting the power and phase of each loudspeaker of the traveling wave tube (2) according to the noise load spectrum of the test, recording the controller output voltage value of the quartz lamp heater (4) according to the target heating temperature requirement, and determining that the vibration slide (1) meets the test requirements of the load level specified in the loading test. To conduct the formal test, the quartz lamp heater (4) first provides the heating load. After reaching the target temperature, the temperature is kept for a set time. Then, the traveling wave tube loads the noise load to the target acoustic load spectrum. Finally, the vibration slide (1) loads the vibration load to the target value and records the test data.

9. The test method for thermoacoustic-vibration coupled box-section structure according to claim 8, characterized in that, The controller output voltage values ​​of the quartz lamp heater (4) are recorded as follows: The test piece is heated to the target heating temperature by a quartz lamp heater (4) and kept at that temperature for 10 minutes. The output voltage value at that time is recorded as the controller output voltage value. If the fluctuation rate of this voltage value exceeds the set value, the average value of all data within 30 seconds is recorded as the controller output voltage value.

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