Device and method for testing the properties of an anti-blast shock wave material

Abstract

A kind of testing device of the performance of explosion-proof shock wave material, including fixing device and test system, the fixing device includes base fixing frame, base and baffle, the front end surface of the baffle is the wave surface for fixing the material to be measured, a plurality of threaded holes for fixing the reflection surface pressure sensor are provided on the baffle, annular grooves are provided around the threaded hole, the front end of the base is provided with the extension section extending forward, the extension section is provided with sliding slot, and the sliding slot is slidably connected with the support rod for fixing the free-field pressure sensor;The test system includes reflection surface pressure sensor, free-field pressure sensor and signal acquisition device, and the reflection surface pressure sensor, free-field pressure sensor are electrically connected with signal acquisition device.The test method using the above testing device can detect the explosion-proof shock wave performance of material in batches, and will not cause permanent damage to the material to be measured.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mechanics, in particular to a testing device and testing method for the performance of an anti-explosion shock wave material. BACKGROUND

[0002] Anti-explosion impact research is attracting more and more attention. The development of protective materials and equipment with high-efficiency shock wave attenuation is crucial for people's health and property protection, and effective anti-explosion shock wave testing devices and detection methods are the basis for such research.

[0003] At present, the testing of the anti-explosion shock wave performance of materials is generally based on the wearing of shaped protective equipment and equipment on simulated dummy for field real explosion and laboratory simulated explosion experiment. This kind of test has high test cost and long cycle, which is not conducive to large-scale testing and comparative analysis to screen high-performance protective materials. In addition, the evaluation of the anti-explosion shock wave performance of materials is usually based on the destruction form of the protective material structure itself, but this index cannot fully reflect the effect of the anti-explosion shock wave of the material. Especially, when the protective material structure itself is not destroyed, the explosion shock wave will also cause damage to the protected target after passing through the material. Therefore, it is necessary to establish a simple but efficient test method for batch testing of the anti-explosion shock wave performance of materials, and to propose a more reasonable test index for evaluating the performance of the protective material structure, which is an urgent problem to be solved in the anti-explosion shock wave test. SUMMARY

[0004] The purpose of the present application is to solve the problems of high test cost, long test cycle, and not conducive to large-scale testing and comparative analysis to screen high-performance protective materials. The testing method of the present application has the advantages of simple equipment, batch detection, high efficiency, and batch detection of the anti-explosion shock wave performance of materials.

[0005] The purpose of the present application is achieved in the following way:

[0006] The application relates to a device for testing the performance of an anti-explosion shock wave material, which comprises a fixing device and a testing system, wherein the fixing device comprises a base fixing frame, a base and a baffle, the base fixing frame is provided with an installation cavity, the base is fixed in the installation cavity, the top end of the base is provided with an upwardly-extending baffle, the front end surface of the baffle is a wave-approaching surface for fixing the material to be tested, a plurality of threaded holes for fixing a reflection surface pressure sensor are arranged on the baffle, annular grooves are arranged around the threaded holes, the front end of the base is provided with a forwardly-extending extension section, a sliding groove is arranged on the extension section, the sliding groove is slidably connected with a supporting rod for fixing a free field pressure sensor, and locking screws for fixing the supporting rod are arranged on the sliding groove; the testing system comprises a reflection surface pressure sensor, a free field pressure sensor and a signal acquisition device, and the reflection surface pressure sensor and the free field pressure sensor are electrically connected with the signal acquisition device.

[0007] The base fixing frame is a rectangular frame structure, and a plurality of installation cavities are arranged on the base fixing frame.

[0008] The wave-approaching surface of the baffle is a concave-convex surface.

[0009] The concave-convex surface is a back-shaped groove surface.

[0010] The application further discloses a testing method for testing the performance of the anti-explosion shock wave material by using the above testing device, and the method comprises the following steps:

[0011] Step 1: installing the testing device according to the number of materials to be tested and completing the pre-test parameter setting of the signal acquisition device;

[0012] Step 2: fixing the material to be tested on the wave-approaching surface of the baffle of the testing device, pressing the material to be tested on the annular grooves and the sensing surface of the reflection surface pressure sensor, so that the sensing surface of the reflection surface pressure sensor is in a sealed environment and is flush with the wave-approaching surface of the baffle, the free field pressure sensor is arranged in front of the material to be tested, the free field pressure sensor is used for measuring the pressure data of the explosion shock wave reaching the interface of the material to be tested, and the testing device with the material to be tested is obtained;

[0013] Step 3: fixing the testing device with the material to be tested on the shock tube test platform or the test position of the field explosion site, arranging the wave-approaching surface of the baffle to face the direction of the explosion shock wave, so that the explosion shock wave generated by the shock tube or the field explosion acts on the surface of the free field pressure sensor and the reflection surface pressure sensor, and the measured pressure data is transmitted to the signal acquisition device;

[0014] Step 4) the signal acquisition device obtains the pressure data, obtains the curves of the interface of the material to be tested and the shock wave after the material to be tested changing with time, and calculates the change information of the shock wave pressure peak, the positive pressure duration and the positive impulse, obtains the performance of the material to be tested attenuating the explosion shock wave, wherein the shock wave overpressure peak measured by the free field pressure sensor in front of the material to be tested is P0, the shock wave overpressure peak measured by the pressure sensor on the reflecting surface after the material to be tested is P1, the attenuation rate of the explosion shock wave overpressure peak of the material to be tested is (P0-P1) / P0x100%, and the performance of the material to be tested preventing the explosion shock wave is obtained.

[0015] Preferably, the greater the driving pressure of the shock tube in step 4), the greater the load of the explosion shock wave.

[0016] Preferably, the greater the explosive equivalent of the field explosion in step 4), the greater the load of the explosion shock wave.

[0017] Preferably, in step 1), 5 kinds of materials to be tested can be fixed on each baffle of the test device, when the number of materials to be tested is ≤5, one baffle, one base and a base fixing frame provided with one mounting cavity are assembled; when 5 kinds < the number of materials to be tested ≤10, two baffles are assembled, and the two baffles are respectively fixed in two mounting cavities of the base fixing frame through respective bases; when 10 kinds < the number of materials to be tested ≤15, three baffles are assembled, and the three baffles are respectively fixed in three mounting cavities of the base fixing frame through respective bases; when 15 kinds < the number of materials to be tested ≤20, four baffles are assembled, and the four baffles are respectively fixed in four mounting cavities of the base fixing frame through respective bases.

[0018] The explosion-proof shock wave material performance testing device of the present application comprises a fixing device and a testing system, the fixing device comprises a base fixing frame, a base and a baffle, the base fixing frame is provided with a mounting cavity, the base is fixed in the mounting cavity, the top end of the base is provided with an upwardly extending baffle, the front end face of the baffle is a wave-approaching face for fixing the material to be tested, a plurality of threaded holes for fixing the reflection surface pressure sensor are arranged on the baffle, and an annular groove is arranged around the threaded hole, so as to avoid the influence of the adhesive used for bonding the material to be tested on the reflection surface pressure sensor and ensure the sensitivity of the sensing surface of the reflection surface pressure sensor. The front end of the base is provided with a forwardly extending extension section, the extension section is provided with a sliding groove, the sliding groove is in sliding fit with a support rod for fixing the free field pressure sensor, and the sliding groove is provided with a locking screw for fixing the support rod; the base fixing frame can be assembled with 1-4 bases, and 1-5 kinds of materials to be tested can be assembled on the baffle, so that the performance of explosion-proof shock wave of up to 20 different materials to be tested can be tested at the same time. The testing system comprises a reflection surface pressure sensor, a free field pressure sensor and a signal acquisition device, and the reflection surface pressure sensor and the free field pressure sensor are electrically connected with the signal acquisition device. Thus, the performance of explosion-proof shock wave of the material to be tested and the dynamic evolution process of the shock wave can be completely measured. The testing device adopts an integrated multi-channel design, reduces the propagation of explosion shock wave through gaps or joints, changes the original propagation law, integrates the fixing device and the testing system together, and avoids the space effect caused by assembly; the fixing device truly reflects the constraint state and dynamic evolution process of the material under the action of explosion shock wave; the material to be tested and the baffle form a sealed test chamber, which effectively prevents the explosion shock wave from entering the test chamber through diffraction and affects the measurement results; the evolution information of the free field and the shock wave pressure after the material can be obtained through the free field pressure sensor and the reflection surface pressure sensor; the multi-channel design can simultaneously test the explosion-proof performance of multiple materials (same or different materials), and the explosion-proof performance comparison between different materials can be carried out.

[0019] The explosion-proof shock wave material performance testing method of the present application arranges and installs the above-mentioned testing device according to the number of materials to be tested, so as to assemble according to the demand, reduce the assembly time and improve the assembly efficiency. The material to be tested, the reflection surface pressure sensor and the free field pressure sensor are fixed at the corresponding positions of the testing device, the sample is complete during the explosion shock wave impact process, and no permanent damage is caused to the sample. The shock tube test adjusts the driving pressure size of the explosion shock wave to obtain different initial shock wave pressures, and the field explosion test adjusts the distance between the ammunition equivalent and the explosion center of the testing device to adjust the driving pressure of the explosion shock wave to obtain different initial shock wave pressures, so as to meet different testing requirements. Then, the pressure data recorded by the pressure sensors before and after the material are analyzed to analyze the attenuation performance of the material to the explosion shock wave.

[0020] The testing device and testing method of the explosion-proof shock wave material performance of the present application have low testing cost, short testing period, simple operation, and can be used for large batch testing and comparative analysis to screen high-performance protective materials. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 The schematic diagram of the testing device and the testing method in the shock tube of the present application is shown in the figure.

[0022] Figure 2 The testing device of the present application is shown in the figure.

[0023] Figure 3 The schematic diagram of the fixing device structure of the testing device of the present application is shown in the figure.

[0024] Figure 4 The side view of the testing device of the present application is shown in the figure.

[0025] Figure 5 The schematic diagram of the base fixing frame structure of the present application which can fix 4 baffle plates is shown in the figure.

[0026] Figure 6 The schematic diagram of the testing device of the present application and the testing method under the field explosion condition is shown in the figure.

[0027] Figure 7 The pressure time history diagram of the testing material tested by the shock tube test platform of the present application is shown in the figure. DETAILED DESCRIPTION

[0028] REFERENCE Figures 1 to 6The utility model provides a kind of test device of the performance of explosion-proof shock wave material, including fixing device and test system, the fixing device includes base fixing frame 1, base 2 and baffle 3, the installation cavity is equipped on the base fixing frame 1, the base fixing frame 1 is rectangular frame structure, the base fixing frame 1 is equipped with multiple installation cavities, the recess for installing the cable of test system is equipped on the base fixing frame 1, the base fixing frame 1 can be proportionally enlarged and reduced according to explosion shock wave generating device and scene design, to be more stable with fixed. The base 2 is fixed in installation cavity by bolt, the top of the base 2 is equipped with the baffle 3 extending upwards, the front end surface of the baffle 3 is the wave surface for fixing the material 7 to be measured, the wave surface of the baffle 3 is concave-convex surface. The concave-convex surface is a back-shaped groove surface. So as to increase the material 7 to be measured and wave surface bonding firm. The baffle 3 is equipped with multiple threaded holes 4 for fixing reflecting surface pressure sensor 9, the threaded hole 4 is fixedly connected reflecting surface pressure sensor 9 by thread, the sensing surface of reflecting surface pressure sensor 9 is flush with the wave surface of baffle 3. Annular groove 5 is arranged around the threaded hole 4, so as to avoid the adhesive for bonding the material to be measured to influence reflecting surface pressure sensor, guarantee the sensitivity of the sensing surface of reflecting surface pressure sensor. The front end of the base 2 is equipped with the extension section extending forward, the extension section is equipped with sliding slot, the sliding slot is slidably connected with the support rod 6 for fixing free field pressure sensor, the sliding slot is equipped with locking screw for fixing support rod 6. The upper end of the support rod 6 is equipped with screw hole, the screw hole is fixedly connected free field pressure sensor 8 by thread, the lower end of support rod 6 is slidably connected with sliding slot, the position of free field pressure sensor 8 is adjusted according to test demand, and then support rod 6 is fixed in sliding slot by rotating locking screw, and the position is determined by the relative position of the material to be measured. The base 2, baffle 3 and extension section are integrated structure. The base fixing frame 1 is equipped with 1-4 installation cavities, the base 2 and baffle 3 are arranged in each installation cavity, the baffle 3 is equipped with 1-5 threaded holes 4, the material to be measured is bonded on the wave surface of baffle 3, covers threaded hole 4, so as to be able to detect the performance of up to 20 different materials to be measured explosion-proof shock wave simultaneously. The test system includes reflecting surface pressure sensor, free field pressure sensor and signal acquisition equipment, and the reflecting surface pressure sensor, free field pressure sensor are electrically connected with signal acquisition equipment. It is used for complete measurement of the performance of the material to be measured explosion-proof shock wave and the dynamic evolution process of shock wave.

[0029] The test method for testing the performance of explosion-proof shock wave material using the above test device can be tested in a shock tube or in a field explosion condition.

[0030] Example 1, the test method for testing the performance of explosion-proof shock wave material in a shock tube is as shown in Figure 1

[0031] ​Step 1) Install the testing device according to the number of materials to be tested. Each baffle of the testing device can fix 5 types of materials to be tested. When the number of materials to be tested is ≤5, assemble one baffle, one base, and a base fixing frame with one mounting cavity; when 5 < number of materials to be tested ≤10, assemble two baffles, each fixed in one of the two mounting cavities of the base fixing frame by its respective base; when 10 < number of materials to be tested ≤15, assemble three baffles, each fixed in one of the three mounting cavities of the base fixing frame by its respective base; when 15 < number of materials to be tested ≤20, assemble four baffles, each fixed in one of the four mounting cavities of the base fixing frame by its respective base. The materials to be tested can be the same type of material from different batches, comparing whether there are batch-to-batch differences in the shock wave attenuation performance of the same type of material; or they can be different types of materials, comparing the differences in shock wave attenuation performance of different types of materials. The free field and reflective surface pressure sensor can be either PCB102A02 or Endevco8530C model sensor. Before testing the signal acquisition equipment, set the parameters according to the sensor type and model. For example, the Endevco 8530C sensor is a bridge sensor, the measurement data is pressure, the input mode is DIF_DC, the constant pressure is 10V, the bridge mode is full bridge, and the sampling frequency is 500KHz.

[0032] Step 2) Fix the material to be tested on the wave-facing surface of the baffle of the testing device, pressing it against the annular groove and the sensing surface of the reflective pressure sensor, so that the sensing surface of the reflective pressure sensor is in a sealed environment. The sensing surface of the reflective pressure sensor is flush with the wave-facing surface of the baffle and is used to measure the pressure data after the explosion shock wave passes through the material to be tested. A free field pressure sensor is provided in front of the material to be tested. The free field pressure sensor is used to measure the pressure data when the explosion shock wave reaches the interface of the material to be tested; thus obtaining the testing device with the material to be tested fixed.

[0033] Step 3) Fix the fixing device of the test apparatus, which holds the material to be tested, to the front of the end baffle inside the shock tube test platform using connectors. Position the baffle's wave-facing surface towards the direction of the explosion shock wave, ensuring the shock wave acts perpendicularly to the wave-facing surface. The shock tube test platform has a through-hole for the test system cables. The cables of the free-field pressure sensor and the reflector pressure sensor pass through this through-hole and connect to the signal acquisition equipment located outside the shock tube test platform. In the shock tube test platform, a driving pressure is set to generate a shock wave (e.g., a driving pressure of 5.5 MPa) to rupture the aluminum diaphragm, causing high-pressure gas to form a shock wave inside the shock tube. This shock wave can directly act on the wave-facing surface of the test apparatus. The greater the driving pressure of the shock tube test, the greater the load of the explosion shock wave. The specific parameters of the driving pressure can be set and adjusted according to experimental requirements.

[0034] The explosion shock wave generated by the shock tube acts on the surface of the free field pressure sensor and the reflecting surface pressure sensor, and the free field pressure sensor and the reflecting surface pressure sensor transmit the measured pressure data to the signal acquisition device.

[0035] Step 4) The signal acquisition device obtains the pressure data, obtains the time-varying curve of the shock wave after the material interface and after the material, and calculates the change information of the shock wave pressure peak, the positive pressure duration and the positive impulse, obtains the performance of the material attenuating the explosion shock wave, and sets the shock wave overpressure peak value measured by the free field pressure sensor in front of the material as P0, and the shock wave overpressure peak value measured by the reflecting surface pressure sensor after the material as P1, then the attenuation rate of the material to the explosion shock wave overpressure peak value is (P0-P1) / P0x100%, and the performance of the material preventing the explosion shock wave is obtained.

[0036] Example 2: Test method for performance of explosion shock wave resistant material under field explosion conditions, as shown in Figure 6

[0037] Step 1) According to the number of materials to be tested, install the test device and complete the parameter setting of the signal acquisition device before testing, and the signal acquisition device parameters are set according to the sensor type and model, such as Endevco8530C sensor measurement type is bridge sensor, measurement data is selected as pressure, input mode is DIF_DC, constant voltage is 10V, bridge mode is full bridge, and sampling frequency is 500KHz.

[0038] Step 2) Fix the material to be tested on the windward surface of the baffle of the test device, press it on the annular groove and the sensing surface of the reflecting surface pressure sensor, so that the sensing surface of the reflecting surface pressure sensor is in a sealed environment, and the sensing surface of the reflecting surface pressure sensor is flush with the windward surface of the baffle, used for measuring the pressure data of the explosion shock wave after passing through the material to be tested, and a free field pressure sensor is arranged in front of the material to be tested, used for measuring the pressure data of the explosion shock wave reaching the material interface; obtain the test device fixed with the material to be tested.

[0039] Step 3) Fix the fixing device of the test device fixed with the material to be tested at the test position of the field explosion site, and make the windward surface of the baffle face the direction of the explosion shock wave, so that the explosion shock wave acts vertically on the windward surface. The larger the explosive equivalent of the field explosion, the greater the load of the explosion shock wave. When the explosive equivalent is the same, the closer the explosive center of the field explosion to the test device, the greater the load of the explosion shock wave. Fix the test device on the ground or fixing device 3m away from the explosion center, keep the test device at the same height as the explosion center, and connect the cable lines of the free field pressure sensor and the reflecting surface pressure sensor to the signal acquisition device located in the safe room.​

[0040] The explosion shock wave generated by the field explosion test acts on the surface of the free field pressure sensor and the reflective surface pressure sensor. The free field pressure sensor and the reflective surface pressure sensor transmit the measured pressure data to the signal acquisition equipment.

[0041] Step 4) The signal acquisition device obtains pressure data, obtains the interface of the material under test and the time change curve of the shock wave after passing through the material under test, and calculates the change information of the peak pressure of the shock wave, the duration of the positive pressure and the positive impulse, so as to obtain the performance of the material under test in attenuating the explosion shock wave. Among them, the peak pressure of the shock wave measured by the free field pressure sensor in front of the material under test is P0, and the peak pressure of the shock wave measured by the pressure sensor on the reflective surface of the material under test is P1. Then the attenuation rate of the peak pressure of the explosion shock wave by the material under test is (P0-P1) / P0×100%, so as to obtain the performance of the material under test in resisting the explosion shock wave.

[0042] Example 3: Performance testing of five different types of explosion shock wave resistant materials, such as... Figure 7 As shown:

[0043] This embodiment tests the performance of five different types of blast shock wave resistant materials under the same test conditions, comparing the differences in shock wave attenuation performance among different types of materials. The pressure-time history graph of the test material was obtained using a shock tube test platform. The horizontal axis represents time (milliseconds), and the vertical axis represents the pressure data of the blast shock wave reaching the interface of the test material or after passing through the test material (kPa). The peak overpressure P0 of the blast shock wave reaching the interface of the test material and the peak overpressure P1 of the blast shock wave after passing through the test material were obtained. The attenuation rate of the test material to the peak overpressure of the blast shock wave was then calculated using the attenuation rate calculation method (P0-P1) / P0×100%, thus obtaining the performance of the test material in attenuating the blast shock wave, i.e., the blast shock wave resistant performance of the test material. Table 1 shows the peak overpressure and attenuation rate of the blast shock wave attenuated by the five different types of blast shock wave resistant materials tested under the same test conditions.

[0044] Table 1. Peak Overpressure and Attenuation Rate of Attenuated Shock Waves of Different Material Types

[0045] .

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications made to the present invention by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. A testing device for the performance of materials resistant to explosion shock waves, characterized in that: The device includes a fixing device and a testing system. The fixing device includes a base fixing frame (1), a base (2), and a baffle (3). The base fixing frame (1) is a rectangular frame structure. The base fixing frame (1) has multiple mounting cavities. The base (2) is fixed in the mounting cavity. The top of the base (2) has an upwardly extending baffle (3). The front end of the baffle (3) is the wave-facing surface for fixing the material to be tested. The baffle (3) has multiple threaded holes (4) for fixing the reflective pressure sensor. The threaded holes (4) are surrounded by an annular groove (5). The front end of the base (2) has a forward-extending extension section. The extension section has a sliding groove. The sliding groove is slidably engaged with the support rod (6) for fixing the free field pressure sensor. The sliding groove has a locking screw for fixing the support rod (6). The testing system includes a reflective pressure sensor, a free field pressure sensor, and a signal acquisition device. The reflective pressure sensor and the free field pressure sensor are electrically connected to the signal acquisition device.

2. The testing apparatus according to claim 1, characterized in that: The wave-facing surface of the baffle (3) is concave and convex.

3. The testing apparatus according to claim 2, characterized in that: The concave and convex surfaces are U-shaped groove surfaces.

4. A test method for testing the performance of explosion-proof shock wave-resistant materials using the test apparatus described in claim 1, characterized in that: The method includes: Step 1) Install the testing device according to the quantity of the material to be tested, and complete the pre-test parameter settings for the signal acquisition equipment; Step 2) Fix the material to be tested on the wave-facing surface of the baffle of the test device, press it against the annular groove and the sensing surface of the reflective pressure sensor. The sensing surface of the reflective pressure sensor is flush with the wave-facing surface of the baffle and is used to measure the pressure data after the explosion shock wave passes through the material to be tested. A free field pressure sensor is provided in front of the material to be tested to measure the pressure data when the explosion shock wave reaches the interface of the material to be tested, thus obtaining the test device with the material to be tested fixed. Step 3) Fix the test device with the material to be tested on the shock tube test platform or the field explosion test position, and set the wave-facing side of the baffle to the direction of the explosion shock wave. The explosion shock wave generated by the shock tube or the field explosion acts on the surface of the free field pressure sensor and the reflective surface pressure sensor, and transmits the measured pressure data to the signal acquisition device. Step 4) The signal acquisition device obtains pressure data, obtains the interface of the material under test and the time change curve of the shock wave after passing through the material under test, calculates the change information of the peak pressure of the shock wave, the duration of the positive pressure and the positive impulse, and obtains the performance of the material under test in attenuating the explosion shock wave. Set the peak pressure of the shock wave measured by the free field pressure sensor in front of the material under test as P0, and the peak pressure of the shock wave measured by the pressure sensor on the reflective surface behind the material under test as P1. Then the attenuation rate of the peak pressure of the explosion shock wave by the material under test is (P0-P1) / P0×100%, and obtain the performance of the material under test in resisting the explosion shock wave.

5. The test method according to claim 4, characterized in that: Step 4) The greater the driving pressure of the shock tube, the greater the load of the explosion shock wave.

6. The test method according to claim 4, characterized in that: Step 4) The greater the yield of the live-fire ammunition, the greater the load of the blast shock wave.

7. The test method according to claim 4, characterized in that: Step 1) Each baffle of the testing device can be fixed with 5 kinds of materials to be tested. When the number of materials to be tested is ≤ 5, one baffle is installed; when 5 kinds < the number of materials to be tested is ≤ 10, two baffles are installed; when 10 kinds < the number of materials to be tested is ≤ 15, three baffles are installed; when 15 kinds < the number of materials to be tested is ≤ 20, four baffles are installed.

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