A high-speed wind tunnel laser energy coupling test model and test method

Abstract

The present application belongs to the field of high-speed wind tunnel test, and discloses a high-speed wind tunnel laser energy coupling test model and a test method. The model main body is a box, a wedge-shaped head is installed at the front end, corresponding openings are arranged on the left and right side walls, a test material is installed on one side opening, and an optical glass window is installed on the other side opening, the test material and the optical glass window jointly close the model main body, so that the model main body inner cavity is isolated from the high-speed wind tunnel airflow; the test method comprises installing a test model, installing a measuring device, fixing a temperature sensor, starting the high-speed wind tunnel, opening a laser emitter, closing the high-speed wind tunnel, obtaining temperature data deviation, repeatedly performing high-speed wind tunnel test, and performing flow field test. The test model and the test method can simulate the flow field characteristics, simulate the laser energy coupling, obtain the temperature change and the temperature distribution of the test material, and obtain the energy coupling efficiency under different flow fields.

Description

Technical Field

[0001] This invention belongs to the field of high-speed wind tunnel testing, specifically relating to a high-speed wind tunnel laser energy coupling test model and test method. Background Technology

[0002] High-energy lasers, characterized by their concentrated direction, high energy density, and rapid transmission speed, are playing an increasingly important role in production and daily life, capable of causing structural damage in a short period. When aircraft move at high speeds in the atmosphere, the surrounding flow field is non-uniform, and supersonic motion generates shock waves. This non-uniform flow field affects the laser's transmission performance and the power density and distribution at the surface of the moving object. Furthermore, the convective heat transfer environment around high-speed aircraft promotes oxidation reactions, and the mechanical erosion effect after material damage also affects the laser's further damaging effect on the material. When a laser irradiates an object's surface, some of the laser light is reflected, some is dissipated into the surrounding environment through heat conduction and radiation, and the remaining laser interacts with the material, causing the material's temperature to rise and ultimately altering its mechanical properties and morphology. The interaction between laser and material is an energy coupling process.

[0003] To effectively predict the characteristics of a laser beam reaching the surface of an aircraft after passing through a high-speed flow field (such as changes in the centroid coordinates and shape of the laser spot), as well as the energy coupling efficiency of the interaction between the laser and the aircraft surface material, relevant experimental research is needed. However, laser irradiation experiments on real aircraft are difficult and costly, and not conducive to obtaining large-scale data. Using high-speed wind tunnel equivalent experiments can reduce the difficulty and cost of experiments, diversify experimental conditions, and obtain abundant experimental data.

[0004] The design of experimental models and the establishment of experimental methods are crucial for conducting equivalent tests in high-speed wind tunnels, directly determining the quality of these tests. Currently, there is an urgent need to develop a laser energy coupling experimental model and method for high-speed wind tunnels. Summary of the Invention

[0005] One technical problem to be solved by the present invention is to provide a high-speed wind tunnel laser energy coupling test model, and another technical problem to be solved by the present invention is to provide a high-speed wind tunnel laser energy coupling test method, so as to overcome the defects of the prior art.

[0006] The high-speed wind tunnel laser energy coupling test model of the present invention includes a wedge head, a model body, test materials, a pressure ring, an optical glass window, a support rod, cables with protective tubes, and a support arm; The model body is a box-shaped structure with a wedge-shaped head installed at the front end. Corresponding through holes are located on the left and right side walls of the model body. One through hole is used to install the test material, which is secured by a pressure ring. The other through hole is used to install an optical glass window. The test material and the optical glass window together seal the model body, isolating the inner cavity of the model body from the high-speed wind tunnel airflow. The outer surface of the test material in contact with the high-speed airflow is the front, and the inner surface where the airflow is still is the back. The rear end of the model body is fixed to a support arm via a support rod. A cable with a protective tube enters the inner cavity of the model body through the inner cavity of the support rod and connects to a temperature sensor fixed within the inner cavity. The temperature sensor contacts the back of the test material.

[0007] Furthermore, the wedge head is a series of wedge heads with different apex angles. By changing the wedge head, the shock wave apex angle can be changed to simulate the flow field distribution around different aircraft.

[0008] Furthermore, the test materials are a series of test material sheets with different thicknesses and materials, and the surface structures of different aircraft are simulated by changing the test materials.

[0009] Furthermore, the temperature sensor comprises several components, each of which is fixed on a mounting bracket within the inner cavity of the model body. The position of each temperature sensor is adjusted and fixed by the mounting bracket to ensure that each temperature sensor is in contact with the back of the non-conductive test material. An insulating layer is provided between the mounting bracket and the conductive test material to ensure that each temperature sensor is in contact with the insulating layer.

[0010] Furthermore, the method for determining contact is as follows: For non-conductive test materials, firstly, replace the non-conductive test material with a conductive test material of the same thickness; secondly, locate the temperature sensors that are not in contact with the conductive test material by measuring the resistance values ​​between each temperature sensor and the conductive test material; thirdly, adjust and fix the corresponding temperature sensor positions using the mounting bracket to ensure that each temperature sensor is in contact with the conductive test material; finally, replace the conductive test material with a non-conductive test material and fix it to the model body using a pressure ring. For conductive test materials, firstly, measure the resistance value between each temperature sensor and the conductive test material to locate the temperature sensor that is not in contact with the conductive test material; secondly, adjust and fix the position of the corresponding temperature sensor using the mounting bracket to ensure that each temperature sensor is in contact with the conductive test material; thirdly, after adding an insulating layer to the back of the conductive test material, fix it to the model body using a pressure ring.

[0011] The high-speed wind tunnel laser energy coupling test method of the present invention includes the following steps: S10. Install the test model; The test model is fixed to the lower wall of the wind tunnel test section using a support arm, with the central axis of the test model coinciding with the central axis of the wind tunnel test section; S20. Install the measuring device; The laser emitter is installed outside the wind tunnel test section. The laser beam emitted by the laser emitter irradiates the test material through the optical window of the wind tunnel test section, causing the test material to produce frontal thermal radiation and back thermal radiation. The frontal thermal radiation of the test material is captured by the front infrared camera, and the back thermal radiation of the test material is captured by the back infrared camera. S30. Fixed temperature sensor; Check the contact between the temperature sensors and the test material, and adjust and fix each temperature sensor. For non-conductive test materials, ensure that each temperature sensor is in contact with the back of the non-conductive test material. For conductive test materials, ensure that each temperature sensor is in contact with the back of the insulating layer. S40. Start the high-speed wind tunnel; According to the test plan, the high-speed wind tunnel was started to generate high-speed airflow at the target speed. The high-speed airflow passed through the wedge head to generate shock waves, simulating the flow field of an aircraft, and a high-speed wind tunnel test was conducted. S50. Turn on the laser emitter; A synchronizer is used to start the laser emitter, which emits a laser beam that passes through the high-speed airflow and shock wave and irradiates the front of the test material. The temperature of the test material rises under the irradiation of the laser beam. An infrared camera on the front of the test material captures an infrared image of the front of the test material and records the temperature change of the front of the test material over time. At the same time, a temperature sensor measures the temperature signal of the back of the test material and records the temperature change of the back of the test material over time. The energy coupling efficiency between the high-speed airflow at the target velocity and the test material is obtained. S60. Close the high-speed wind tunnel; Once the preset test time is reached, or the front of the test material reaches the set temperature, the laser emitter is turned off, all temperature sensors and the front infrared camera stop collecting data, and the high-speed wind tunnel is shut down. S70. Obtain temperature data deviation; The mounting bracket and insulation layer introduce data deviations between the temperature sensors and the rear infrared camera. The mounting bracket, temperature sensors, and insulation layer are removed. Under high-speed airflow at the same target velocity, the front infrared camera acquires infrared images of the front of the test material and records the temperature change of the front of the test material over time; the rear infrared camera acquires infrared images of the back of the test material and records the temperature change of the back of the test material over time. By comparing the infrared images of the back of the test material with the temperature signals measured by the temperature sensors, the temperature data deviation is obtained. The temperature data deviation is then used to correct the temperature signals measured by each temperature sensor on the back of the test material. S80. Repeat the high-speed wind tunnel test; According to the requirements of the test plan, change the target speed of the high-speed airflow, or change the test material under the same target speed of the high-speed airflow, and repeat S40~S80 to obtain the energy coupling efficiency under various test conditions under the blowing conditions. S90. Conduct a flow-free test; According to the test plan, without opening the high-speed wind tunnel, the test materials were changed, and S50 and S70 were repeated to obtain the energy coupling efficiency under various test conditions in the absence of wind.

[0012] The high-speed wind tunnel laser energy coupling test model of the present invention can equivalently simulate the flow field characteristics around an aircraft, and facilitates the installation of test material samples.

[0013] The high-speed wind tunnel laser energy coupling test method of the present invention can obtain the temperature change of the test material under laser action over time, as well as the temperature distribution in the material; it can simulate the energy coupling between the laser and the target test material through the flow field around the high-speed aircraft, and simultaneously obtain the temperature change of the test material over time during the energy coupling process, as well as the temperature distribution in the test material at different times; it can quickly measure the laser spot shape and energy distribution with or without a flow field, accurately measure the temperature change of the test material over time, and the material damage time; it can also obtain the energy coupling efficiency under different flow fields by comparing data with or without a flow field.

[0014] In summary, the high-speed wind tunnel laser energy coupling test model and test method of the present invention can equivalently simulate the flow field characteristics, simulate laser energy coupling, obtain the temperature change and temperature distribution of the test material, and obtain the energy coupling efficiency under different flow fields. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the high-speed wind tunnel laser energy coupling test model of the present invention; Figure 2 This is a schematic diagram of the installation of the high-speed wind tunnel laser energy coupling test model of the present invention.

[0016] In the diagram, 1. Wedge head; 2. Model body; 3. Test material; 4. Pressure ring; 5. Optical glass window; 6. Support rod; 7. Cable; 8. Support arm; 9. High-speed airflow; 10. Shock wave; 11. Laser emitter; 12. Laser beam; 13. Insulation layer; 14. Mounting frame; 15. Temperature sensor; 16. Frontal thermal radiation of test material; 17. Frontal infrared camera; 18. Backward thermal radiation of test material; 19. Backward infrared camera; 20. Wind tunnel test section. Detailed Implementation

[0017] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] Example: Figure 1 , Figure 2 As shown, the high-speed wind tunnel laser energy coupling test model of this embodiment includes a wedge head 1, a model body 2, test materials 3, a pressure ring 4, an optical glass window 5, a support rod 6, a cable with a protective tube 7, and a support arm 8. The model body 2 is a box-shaped structure, with a wedge-shaped head 1 installed at the front end. Corresponding through holes are provided on the left and right side walls of the model body 2. Test material 3 is installed in one through hole and fixed by a pressure ring 4. Optical glass window 5 is installed in the other through hole. Test material 3 and optical glass window 5 together seal the model body 2, isolating the inner cavity of the model body 2 from the high-speed wind tunnel airflow. The outer surface of the test material 3 in contact with the high-speed airflow 9 is the front, and the inner surface where the airflow is still is the back. The rear end of the model body 2 is fixed to the support arm 8 by a support rod 6. A cable 7 with a protective tube enters the inner cavity of the model body 2 through the inner cavity of the support rod 6 and connects to a temperature sensor 15 fixed in the inner cavity. The temperature sensor 15 contacts the back of the test material 3.

[0019] Furthermore, the wedge head 1 is a series of wedge heads with different apex angles. By changing the wedge head 1, the shock wave apex angle can be changed to simulate the flow field distribution around different aircraft.

[0020] Furthermore, the test material 3 is a series of test material sheets with different thicknesses and materials, and the surface structure of different aircraft is simulated by changing the test material 3.

[0021] Furthermore, the temperature sensor 15 has several components, and each temperature sensor 15 is fixed on the mounting bracket 14 inside the model body 2. The position of each temperature sensor 15 is adjusted and fixed by the mounting bracket 14 to ensure that each temperature sensor 15 is in contact with the back of the non-conductive test material 3. An insulating layer 13 is provided between the mounting bracket 14 and the conductive test material 3 to ensure that each temperature sensor 15 is in contact with the insulating layer 13.

[0022] Furthermore, the method for determining contact is as follows: For the non-conductive test material 3, firstly, the non-conductive test material 3 is replaced with a conductive test material 3 of the same thickness; secondly, by measuring the resistance value between each temperature sensor 15 and the conductive test material 3, the temperature sensor 15 that is not in contact with the conductive test material 3 is located; thirdly, the position of the corresponding temperature sensor 15 is adjusted and fixed by the mounting bracket 14 to ensure that each temperature sensor 15 is in contact with the conductive test material 3; finally, the conductive test material 3 is replaced with a non-conductive test material 3 and fixed to the model body 2 by the pressure ring 4. For the conductive test material 3, firstly, the resistance value between each temperature sensor 15 and the conductive test material 3 is measured to locate the temperature sensor 15 that is not in contact with the conductive test material 3; secondly, the position of the corresponding temperature sensor 15 is adjusted and fixed by the mounting bracket 14 to ensure that each temperature sensor 15 is in contact with the conductive test material 3; thirdly, after adding an insulating layer 13 to the back of the conductive test material 3, it is fixed to the model body 2 by the pressure ring 4.

[0023] The high-speed wind tunnel laser energy coupling test method of this embodiment includes the following steps: S10. Install the test model; The test model is fixed to the lower wall of the wind tunnel test section 20 by the support arm 8, and the central axis of the test model coincides with the central axis of the wind tunnel test section 20. S20. Install the measuring device; The laser emitter 11 is installed outside the wind tunnel test section 20. The laser beam 12 emitted by the laser emitter 11 irradiates the test material 3 through the optical window of the wind tunnel test section 20, causing the test material 3 to generate front thermal radiation 16 and back thermal radiation 18. The front thermal radiation 16 is captured by the front infrared camera 17, and the back thermal radiation 18 is captured by the back infrared camera 19. S30. Fixed temperature sensor 15; Check the contact between the temperature sensor 15 and the test material 3, and adjust and fix each temperature sensor 15; for non-conductive test material 3, ensure that each temperature sensor 15 is in contact with the back of the non-conductive test material 3; for conductive test material 3, ensure that each temperature sensor 15 is in contact with the back of the insulating layer 13. S40. Start the high-speed wind tunnel; According to the requirements of the test plan, the high-speed wind tunnel is started to generate a high-speed airflow 9 at the target speed. The high-speed airflow 9 flows through the wedge head 1 to generate a shock wave 10, simulating the flow field of an aircraft, and a high-speed wind tunnel test is carried out. S50. Turn on laser emitter 11; A synchronizer is used to activate the laser emitter 11, which emits a laser beam 12. The laser beam 12 passes through the high-speed airflow 9 and the shock wave 10 and irradiates the front of the test material 3. The temperature of the test material 3 rises under the irradiation of the laser beam 12. The front infrared camera 17 acquires infrared images of the front of the test material 3 and records the temperature change of the front of the test material 3 over time. At the same time, the temperature sensor 15 measures the temperature signal of the back of the test material 3 and records the temperature change of the back of the test material 3 over time. The energy coupling efficiency between the high-speed airflow 9 and the test material 3 at the target speed is obtained. S60. Close the high-speed wind tunnel; After the preset test time is reached, or the front of the test material 3 reaches the set temperature, the laser emitter 11 is turned off, the temperature sensors 15 and the front infrared camera 17 are stopped from collecting data, and the high-speed wind tunnel is shut down. S70. Obtain temperature data deviation; The mounting bracket 14 and insulating layer 13 introduce data deviations between the temperature sensors 15 and the rear infrared camera 19. The mounting bracket 14, temperature sensors 15, and insulating layer 13 are removed. Under a high-speed airflow 9 at the same target speed, the front infrared camera 17 acquires an infrared image of the front of the test material 3 and records the temperature change of the front of the test material 3 over time. The rear infrared camera 19 acquires an infrared image of the back of the test material 3 and records the temperature change of the back of the test material 3 over time. By comparing the infrared image of the back of the test material 3 with the temperature signal measured by the temperature sensors 15, the temperature data deviation is obtained. The temperature data deviation is then used to correct the temperature signal measured by each temperature sensor 15 on the back of the test material 3. S80. Repeat the high-speed wind tunnel test; According to the requirements of the test plan, change the target speed of the high-speed airflow 9, or under the same target speed of the high-speed airflow 9, change the test material 3 and repeat S40~S80 to obtain the energy coupling efficiency under various test conditions under the blowing conditions. S90. Conduct a flow-free test; According to the requirements of the test plan, without turning on the high-speed wind tunnel, replace test material 3, repeat S50 and S70, and obtain the energy coupling efficiency under various test conditions in the absence of wind.

[0024] Although the embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. For those skilled in the art, all features disclosed in the present invention, or all steps in all methods or processes disclosed, except for mutually exclusive features and / or steps, can be combined in any way without departing from the principles of the present invention. The present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A high-speed wind tunnel laser energy coupling test model, characterized in that, The test model includes a wedge head (1), a model body (2), test materials (3), a pressure ring (4), an optical glass window (5), a support rod (6), a cable with a protective tube (7), and a support arm (8). The model body (2) is a box, and a wedge head (1) is installed at the front end of the model body (2). Corresponding through holes are provided on the left and right side walls of the model body (2). Test material (3) is installed in one through hole and fixed by pressure ring (4). Optical glass window (5) is installed in the other through hole. Test material (3) and optical glass window (5) together seal the model body (2) so that the inner cavity of the model body (2) is isolated from the high-speed wind tunnel airflow. The outer surface of the test material (3) in contact with the high-speed airflow (9) is the front, and the inner surface where the airflow is still is the back. The rear end of the model body (2) is fixed to the support arm (8) by the support rod (6). The cable (7) with protective tube enters the inner cavity of the model body (2) through the inner cavity of the support rod (6) and connects to the temperature sensor (15) fixed in the inner cavity. The temperature sensor (15) contacts the back of the test material (3).

2. The high-speed wind tunnel laser energy coupling test model according to claim 1, characterized in that, The wedge head (1) is a series of wedge heads with different apex angles. By changing the wedge head (1), the shock wave apex angle can be changed to simulate the flow field distribution around different aircraft.

3. The high-speed wind tunnel laser energy coupling test model according to claim 1, characterized in that, The test material (3) is a series of test material sheets with different thicknesses and materials. The surface structure of different aircraft is simulated by changing the test material (3).

4. The high-speed wind tunnel laser energy coupling test model according to claim 1, characterized in that, The temperature sensor (15) has several units, and each temperature sensor (15) is fixed on the mounting bracket (14) inside the model body (2). The position of each temperature sensor (15) is adjusted and fixed by the mounting bracket (14) to ensure that each temperature sensor (15) is in contact with the back of the non-conductive test material (3). An insulating layer (13) is provided between the mounting bracket (14) and the conductive test material (3) to ensure that each temperature sensor (15) is in contact with the insulating layer (13).

5. The high-speed wind tunnel laser energy coupling test model according to claim 4, characterized in that, The method for determining contact is as follows: For the non-conductive test material (3), firstly, the non-conductive test material (3) is replaced with a conductive test material (3) of the same thickness; secondly, by measuring the resistance value between each temperature sensor (15) and the conductive test material (3), the temperature sensor (15) that is not in contact with the conductive test material (3) is located; thirdly, the position of the corresponding temperature sensor (15) is adjusted and fixed by the mounting bracket (14) to ensure that each temperature sensor (15) is in contact with the conductive test material (3); finally, the conductive test material (3) is replaced with a non-conductive test material (3) and fixed on the model body (2) by the pressure ring (4); For the conductive test material (3), firstly, measure the resistance value between each temperature sensor (15) and the conductive test material (3) to find the temperature sensor (15) that is not in contact with the conductive test material (3); secondly, adjust and fix the position of the corresponding temperature sensor (15) through the mounting bracket (14) to ensure that each temperature sensor (15) is in contact with the conductive test material (3); thirdly, after adding an insulating layer (13) to the back of the conductive test material (3), fix it to the model body (2) through the pressure ring (4).

6. A high-speed wind tunnel laser energy coupling test method, used in any one of the high-speed wind tunnel laser energy coupling test models described in claims 1 to 5, characterized in that, Includes the following steps: S10. Install the test model; The test model is fixed to the lower wall of the wind tunnel test section (20) by the support arm (8), and the central axis of the test model coincides with the central axis of the wind tunnel test section (20); S20. Install the measuring device; The laser emitter (11) is installed outside the wind tunnel test section (20). The laser beam (12) emitted by the laser emitter (11) irradiates the test material (3) through the optical window of the wind tunnel test section (20), causing the test material (3) to generate front thermal radiation (16) and back thermal radiation (18). The front thermal radiation (16) is captured by the front infrared camera (17), and the back thermal radiation (18) is captured by the back infrared camera (19). S30. Fixed temperature sensor (15); Check the contact between the temperature sensor (15) and the test material (3), and adjust and fix each temperature sensor (15); for non-conductive test material (3), ensure that each temperature sensor (15) is in contact with the back of the non-conductive test material (3); for conductive test material (3), ensure that each temperature sensor (15) is in contact with the back of the insulating layer (13). S40. Start the high-speed wind tunnel; According to the requirements of the test plan, the high-speed wind tunnel was started to generate a high-speed airflow (9) at the target speed. The high-speed airflow (9) flowed through the wedge head (1) to generate a shock wave (10), simulating the flow field of the aircraft, and the high-speed wind tunnel test was carried out. S50. Turn on the laser emitter (11). A synchronizer is used to start the laser emitter (11), which emits a laser beam (12). The laser beam (12) passes through the high-speed airflow (9) and the shock wave (10) and irradiates the front of the test material (3). The temperature of the test material (3) rises under the irradiation of the laser beam (12). The front infrared camera (17) collects the infrared image of the front of the test material (3) and records the temperature change of the front of the test material (3) over time. At the same time, the temperature sensor (15) measures the temperature signal of the back of the test material (3) and records the temperature change of the back of the test material (3) over time. The energy coupling efficiency between the high-speed airflow (9) and the test material (3) at the target speed is obtained. S60. Close the high-speed wind tunnel; After the preset test time is reached, or the front of the test material (3) reaches the set temperature, turn off the laser emitter (11), stop the temperature sensors (15) and the front infrared camera (17) from collecting data, and shut down the high-speed wind tunnel. S70. Obtain temperature data deviation; The mounting bracket (14) and the insulating layer (13) cause data deviations between the temperature sensors (15) and the rear infrared camera (19); remove the mounting bracket (14), the temperature sensors (15) and the insulating layer (13); under the same target speed high-speed airflow (9), the front infrared camera (17) collects infrared images of the front of the test material (3) and records the temperature change of the front of the test material (3) over time; the rear infrared camera (19) collects infrared images of the back of the test material (3) and records the temperature change of the back of the test material (3) over time; by comparing the infrared images of the back of the test material (3) with the temperature signals of the back of the test material (3) measured by the previous temperature sensors (15), the temperature data deviation is obtained; the temperature signals of the back of the test material (3) measured by the temperature sensors (15) are corrected by the temperature data deviation. S80. Repeat the high-speed wind tunnel test; According to the requirements of the test plan, change the target speed of the high-speed airflow (9), or change the test material (3) under the same target speed of the high-speed airflow (9), repeat S40~S80, and obtain the energy coupling efficiency under various test conditions under the blowing conditions; S90. Conduct a flow-free test; According to the requirements of the test plan, the high-speed wind tunnel was not turned on, the test material was replaced (3), and S50 and S70 were repeated to obtain the energy coupling efficiency under various test conditions in the absence of wind.

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