Solid propellant oblique impact extrusion-friction force high-frequency decoupling testing device

Abstract

The invention discloses a solid propellant oblique impact extrusion-friction force high-frequency decoupling testing device, and relates to the technical field of aerospace power. The invention provides a set of device for calculating an extrusion-friction coupling force by testing a group of orthogonal forces in an oblique impact process of a solid propellant. The device comprises three parts, namely a test loading part, a data measuring part and an anti-explosion and restraining part. Inclined impact tests with different impact speeds and angles can be carried out by replacing a punch / wedge-shaped seat combination of the test loading part, the loading part is visualized through structural design, and an inclined impact process is shot by using optical equipment such as a high-speed camera and the like; a group of orthogonally arranged high-frequency force sensors are used for collecting data to solve the extrusion-friction coupling force. Compared with the prior art, the high-speed photographic image in the response process can be obtained, the extrusion force and friction force borne by the sample can be obtained, the adjustable range of device parameters is wide, the device is provided with an anti-explosion safety protection structure, the overall size is small, and the machining cost is low.

Description

Technical Field

[0001] The present invention relates to the field of aerospace power technology, and in particular to a high-frequency decoupling test device for the extrusion-friction coupling force in a solid propellant oblique impact stimulation ignition scenario. Background Art

[0002] Solid propellants are a type of chemical product that releases energy by burning and doing work. They are widely used in aerospace propulsion systems and rocket weapons. Solid propellants can exist stably under certain storage conditions. However, when they are accidentally dropped or pierced by sharp objects, they may ignite due to strong extrusion-friction coupling stimulation, leading to explosion accidents. Therefore, designing a test device to perform high-fidelity simulation of the propellant extrusion-friction stimulation ignition scenario and studying the ignition mechanism is of great significance for improving the intrinsic safety of aerospace engines and rocket weapons.

[0003] To study the safety performance of solid propellants under extrusion and friction stimulation, commonly used test equipment are drop hammer impact testers, SHPB (split Hopkinson pressure bar), Kozlov friction pendulum, BAM tribometer, ABL tribometer and other equipment with relatively mature technology levels. However, these equipment can only carry out single-factor stimulation ignition of solid propellants. Accidental ignition caused by the fall of solid propellants or the penetration of sharp objects is often caused by the coupling effect of extrusion and friction. Therefore, some researchers have designed an oblique impact ignition test in which the propellant free falls and hits a rough wedge surface. However, the data obtained only have response process images, lacking load tests. In addition, the posture and speed of the propellant when it hits the wedge surface are greatly affected by the initial state, and the test results are not repeatable. It is difficult for existing test equipment to perform high-fidelity simulation of the oblique impact extrusion-friction multi-factor coupled stimulation ignition scenario of solid propellants and to perform high-precision, high-frequency decoupling tests on the coupled loads in the response process.

[0004] In order to solve the above problems, the present invention proposes a solid propellant oblique impact extrusion-friction force high-frequency decoupling test device. Summary of the invention

[0005] The purpose of the present invention is to provide a solid propellant oblique impact extrusion-friction high frequency decoupling test device to solve the problems raised in the background technology:

[0006] Existing test equipment is difficult to simulate the oblique impact extrusion-friction multi-factor coupled stimulation ignition scenario of solid propellants with high fidelity and to perform high-precision, high-frequency decoupling tests on the coupled loads in the response process. The present invention realizes the extrusion-friction coupled loading of the specimen by using a replaceable punch / wedge seat combination in the test loading part, collects data through a set of orthogonally arranged high-frequency force sensors to resolve the extrusion-friction coupling force, designs a slideway to make the punch slide uniaxially to ensure that the load data measured under the same oblique impact loading intensity has good repeatability, and visualizes the loading part through structural design and uses optical equipment such as high-speed cameras to shoot the oblique impact process.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] A solid propellant oblique impact extrusion-friction force high-frequency decoupling test device, the device is arranged on an aluminum alloy guide rail, and the device includes a test loading mechanism, a data acquisition mechanism, and an explosion-proof-restraint mechanism;

[0009] The test loading mechanism comprises an impact cylinder, a bullet rod, a gun barrel, a striking rod, a punch, and a wedge-shaped seat; the impact cylinder is externally connected to a high-pressure gas source, and a valve can be opened to release gas to accelerate the movement of the bullet rod in the gun barrel; the bullet rod collides with the striking rod after acceleration; the punch is fixedly connected to the end of the striking rod away from the gun barrel;

[0010] The data acquisition mechanism includes a horizontal force sensor, a vertical force sensor, a data acquisition box, a high-speed camera and an LED point light source; the horizontal force sensor is fixedly installed on the horizontal right side of the wedge seat, and is used to measure the horizontal component of the oblique impact loading of the sample; the vertical force sensor is fixedly installed below the wedge seat vertically, and is used to measure the vertical component of the oblique impact loading of the sample; the data acquisition box has a built-in charge amplifier and a data acquisition card, which are used to synchronously collect data of the horizontal force sensor and the vertical force sensor through multiple channels; the high-speed camera and the LED point light source are installed on one side of the test loading mechanism, and the high-speed camera uses the LED point light source for field of view fill light to capture high-temporal and spatial resolution images of the oblique impact response process of the sample;

[0011] The explosion-proof restraint mechanism includes an observation window, a cover plate, a slide, a bracket, a base, and an aluminum alloy guide rail; the observation window is arranged on the front and rear sides of the sample loading mechanism, and is made of sapphire glass with high light transmittance and high hardness, which has a strong protective effect on the potential explosion and powder splashing hazards of the test; the cover plate is arranged at the top of the device, and adopts a detachable design. The detachable cover plate structure makes the installation and replacement of test loading parts and sensors and other components more convenient; the slide is fixedly installed inside the test loading mechanism, and the punch is installed inside the slide; the bracket is located at the fixed structure on the lower side and right side of the slide, which is used to support the slide and install the force sensor; the base is installed on the aluminum alloy guide rail.

[0012] Preferably, a sample is clamped between the punch and the wedge seat, and after being impacted by the punch, the sample is subjected to extrusion-friction coupling stimulation on the inclined surface between the punch and the wedge seat, so as to realize oblique impact tests with different impact speeds and angles.

[0013] Preferably, cylindrical needle rollers are provided on the upper and lower sides of the slideway, and the punch slides uniaxially in the slideway to ensure that the load data measured under the same oblique impact loading intensity has good repeatability.

[0014] Preferably, the horizontal force sensor and the vertical force sensor are orthogonally arranged, and the horizontal force sensor and the vertical force sensor are piezoelectric force sensors with a resonance frequency of >70kHZ, which are used for high-frequency collection of impact load data during oblique impact.

[0015] Preferably, the overlapping portion of the lower side of the slideway and the wedge-shaped seat is hollowed out, so that the vertical force of the sample on the wedge-shaped seat is fully transmitted to the vertical force sensor, thereby ensuring the reliability of the vertical force measurement.

[0016] Preferably, the high-speed camera visually photographs the movements of the punch, the specimen, and the wedge seat of the test loading part through the observation window.

[0017] Preferably, the vertical side plate of the base is provided with a mounting slot, and the bracket is mounted on the vertical side plate of the base through bolts and the mounting slot, and the mounting height can be changed as needed.

[0018] A solid propellant oblique impact extrusion-friction high frequency decoupling test method based on the above device comprises the following steps:

[0019] S1: Clamp the specimen between the punch and the wedge-shaped seat, and adjust the mounting height of the bracket to align the cross-sectional midlines of the bullet rod and the impact rod;

[0020] S2: Debug the data acquisition part and put it in the trigger-waiting state;

[0021] S3: First trigger the data acquisition system, then open the air valve of the impact cylinder, so that the bullet rod accelerates in the barrel and collides with the impact rod, and the punch hits the sample obliquely;

[0022] S4: After the sample has responded, check and save the test data, clean the reaction residues and stains in the device, check the position of each moving part in the device and restore it.

[0023] Compared with the prior art, the present invention provides a solid propellant oblique impact extrusion-friction high-frequency decoupling test device, which has the following beneficial effects:

[0024] The present invention proposes a solid propellant oblique impact extrusion-friction force high-frequency decoupling test device by improving and optimizing the structure of an existing solid propellant oblique impact test device. The present invention uses a replaceable punch / wedge seat combination in the test loading part to realize the extrusion-friction coupling loading of the sample; secondly, the present invention collects data through a group of orthogonally arranged high-frequency force sensors to solve the extrusion-friction coupling force, and designs a slideway to make the punch slide uniaxially to ensure that the load data measured under the same oblique impact loading intensity has good repeatability, and the loading part is visualized through structural design, and the oblique impact process is photographed using optical equipment such as a high-speed camera.

[0025] The present invention can realize high-frequency decoupling test of the extrusion-friction coupling force in the oblique impact process of solid propellant, the test loading position is visualized, the main parts are easy to disassemble and replace, the device parameters have a wide adjustable range, the device has an explosion-proof safety protection structure, the overall size is small, and the processing cost is low. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the overall layout of the device mentioned in Example 1 of the present invention;

[0027] Figure 2 It is a front cross-sectional view of the test loading part of the device mentioned in Example 1 of the present invention.

[0028] Description of the markings in the figure:

[0029] 1. Impact cylinder; 2. Bullet rod; 3. Gun barrel; 4. Observation window; 5. Cover plate; 6. Slide; 7. Impact rod; 8. Punch; 9. Specimen; 10. Wedge seat; 11. Horizontal force sensor; 12. Bracket; 13. Vertical force sensor; 14. Base; 15. Aluminum alloy guide rail; 16. Data acquisition box; 17. High-speed camera; 18. LED point light source. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0031] The present invention improves the solid propellant oblique impact test device, realizes the extrusion-friction coupling loading of the sample by using a replaceable punch / wedge seat combination in the test loading part, collects data through a group of orthogonally arranged high-frequency force sensors to solve the extrusion-friction coupling force, designs a slideway to make the punch slide uniaxially to ensure that the load data measured under the same oblique impact loading intensity has good repeatability, visualizes the loading part through structural design, and uses optical equipment such as high-speed cameras to shoot the oblique impact process. The present invention can realize high-frequency decoupling test of the extrusion-friction coupling force of the solid propellant oblique impact process, visualizes the test loading part, and the main parts are easy to disassemble and replace. The device parameters have a wide adjustable range and have an explosion-proof safety protection structure. The test device of the present invention can be installed on the SHPB equipment with relatively mature technology as an oblique impact extrusion-friction coupling loading function expansion module. The overall size of the device is about 15cm×10cm×5cm, and the overall size is small and the processing cost is low. Specifically include the following contents.

[0032] Embodiment 1:

[0033] See also Figure 1-2 , the present invention proposes a solid propellant oblique impact extrusion-friction force high-frequency decoupling test device, the device is arranged on an aluminum alloy guide rail 15, and is composed of a test loading mechanism, a data acquisition mechanism, and an explosion-proof-restraint mechanism;

[0034] The test loading mechanism includes an impact cylinder 1, a bullet rod 2, a barrel 3, a strike rod 7, a punch 8, a sample 9, and a wedge seat 10; the impact cylinder 1 is externally connected to a high-pressure gas source, and a valve can be opened to release gas to accelerate the bullet rod 2 in the barrel 3; the bullet rod 2 collides with the strike rod 7 after acceleration; the punch 8 is fixedly connected to the strike rod 7 and is thus passively accelerated; the sample 9 is clamped between the punch 8 and the wedge seat 10, and after being struck by the punch 8, it is subjected to extrusion-friction coupling stimulation on the inclined surface between the punch 8 and the wedge seat 10;

[0035] The data acquisition part includes a horizontal force sensor 11, a vertical force sensor 13, a data acquisition box 16, a high-speed camera 17, and an LED point light source 18; the horizontal force sensor 11 is placed on the right side of the wedge seat 10 to measure the horizontal force component of the oblique impact loading of the sample; the vertical force sensor 13 is placed vertically below the wedge seat 10 to measure the vertical force component of the oblique impact loading of the sample; the data acquisition box 16 has a built-in charge amplifier and a data acquisition card, which can synchronously collect data from the horizontal force sensor 11 and the vertical force sensor 13 through multiple channels; the high-speed camera 17 uses the LED point light source 18 for field of view fill light to capture high-temporal and spatial resolution images of the oblique impact response process of the sample;

[0036] The explosion-proof and restraint part includes an observation window 4, a cover plate 5, a slide 6, a bracket 12, a base 14, and an aluminum alloy guide rail 15; the observation window 4 is arranged on the front and rear sides of the sample loading part, and is made of sapphire glass with high light transmittance and high hardness, which has a strong protective effect on the potential explosion and powder splashing hazards of the test; the cover plate 5 is located on the upper side of the device, and the detachable cover plate 5 structure makes the installation and replacement of the test loading part and sensor components more convenient; cylindrical roller needles are arranged on the upper and lower sides of the slide 6, allowing the punch 8 to slide uniaxially in the slide 6; the main function of the bracket 12 is to support the slide 6 and install the force sensor, including the fixed structure located on the lower and right sides of the slide 6; the base 14 is installed on the aluminum alloy guide rail 15 of the SHPB equipment.

[0037] During the test, first clamp the sample 9 between the punch 8 and the wedge seat 10, adjust the installation height of the bracket 12, and align the cross-sectional center lines of the bullet rod 2 and the impact rod 7; then debug the data acquisition part and put it in a triggering state; first trigger the data acquisition system, then open the air valve of the impact cylinder 1, so that the bullet rod 2 collides with the impact rod 7 after accelerating in the barrel 3, and the punch 8 hits the sample 9 obliquely; finally, wait for the sample 9 to respond, check and save the test data, clean the reaction residues and stains in the device, check the position of each moving part in the device and restore it.

[0038] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A solid propellant oblique impact extrusion-friction high-frequency decoupling test device, the device is arranged on an aluminum alloy guide rail (15), characterized in that: The device includes a test loading mechanism, a data acquisition mechanism, and an explosion-proof-restraint mechanism; The test loading mechanism comprises an impact cylinder (1), a bullet rod (2), a gun barrel (3), a striker rod (7), a punch (8), and a wedge seat (10); the impact cylinder (1) is externally connected to a high-pressure gas source and is used to drive the bullet rod (2) to accelerate in the gun barrel (3); the bullet rod (2) collides with the striker rod (7) after acceleration; the punch (8) is fixedly connected to the end of the striker rod (7) away from the gun barrel (3); The data acquisition mechanism comprises a horizontal force sensor (11), a vertical force sensor (13), a data acquisition box (16), a high-speed camera (17) and an LED point light source (18); the horizontal force sensor (11) is fixedly mounted on the horizontal right side of the wedge-shaped seat (10) and is used to measure the horizontal component force of the oblique impact loading of the sample; the vertical force sensor (13) is fixedly mounted below the wedge-shaped seat (10) and is used to measure the vertical component force of the oblique impact loading of the sample; the data acquisition box (16) has a built-in charge amplifier and a data acquisition card, which are used to synchronously acquire data of the horizontal force sensor (11) and the vertical force sensor (13) through multiple channels; the high-speed camera (17) and the LED point light source (18) are mounted on one side of the test loading mechanism, and the high-speed camera (17) uses the LED point light source (18) to perform field of view fill light to capture a high-temporal and spatial resolution image of the oblique impact response process of the sample; The explosion-proof-restraint mechanism comprises an observation window (4), a cover plate (5), a slideway (6), a bracket (12), a base (14), and an aluminum alloy guide rail (15); the observation window (4) is arranged at the front and rear sides of the sample loading mechanism, and is made of sapphire glass with high light transmittance and high hardness; the cover plate (5) is arranged at the top of the device, and is detachable; the slideway (6) is fixedly installed inside the test loading mechanism, and the punch (8) is installed inside the slideway (6); the bracket (12) is a fixed structure located at the lower side and right side of the slideway (6), and is used to support the slideway (6) and install a force sensor; the base (14) is installed on the aluminum alloy guide rail (15).

2. A solid propellant oblique impact extrusion-friction high frequency decoupling test device according to claim 1, characterized in that: A sample (9) is clamped between the punch (8) and the wedge-shaped seat (10). After being impacted by the punch (8), the sample is subjected to extrusion-friction coupling stimulation on the inclined surface between the punch (8) and the wedge-shaped seat (10), so as to realize an oblique impact test at different impact speeds and angles.

3. A solid propellant oblique impact extrusion-friction high frequency decoupling test device according to claim 1, characterized in that: The upper and lower sides of the slideway (6) are both provided with cylindrical needle rollers, and the punch (8) slides uniaxially in the slideway (6).

4. A solid propellant oblique impact extrusion-friction force high frequency decoupling test device according to claim 1, characterized in that: The horizontal force sensor (11) and the vertical force sensor (13) are arranged orthogonally. The horizontal force sensor (11) and the vertical force sensor (13) are piezoelectric force sensors with a resonance frequency of >70 kHz, and are used for high-frequency collection of impact load data during an oblique impact process.

5. The solid propellant oblique impact extrusion-friction high frequency decoupling test device according to claim 1, characterized in that: The high-speed camera (17) takes visual photos of the movements of the punch (8), the test specimen (9) and the wedge-shaped seat (10) of the test loading part through the observation window (4).

6. A solid propellant oblique impact extrusion-friction force high frequency decoupling test device according to claim 1, characterized in that: The vertical side plate of the base (14) is provided with a mounting slot hole, and the bracket (12) is mounted on the vertical side plate of the base (14) through bolts and the mounting slot hole.

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