Cylindrical rm instability perturbation growth material strength measurement experiment system and method thereof

Abstract

The application discloses a cylindrical RM instability strength measurement experiment system and method, and belongs to the technical field of fluid mechanics. The cylindrical RM instability disturbance growth material strength measurement experiment system comprises an experiment device and a measurement system; the experiment device comprises a driving sleeve and a preset disturbance target, and the preset disturbance target is coaxially arranged in the driving sleeve. The cylindrical RM instability strength measurement experiment system and method provided by the application can precisely measure the disturbance growth speed, amplitude, interface morphology and other parameters when high-precision impact loading disturbance targets and filling media in the disturbance targets in the driving sleeve cylindrical implosion are carried out, the strength of the material is calculated by using fluid dynamics numerical simulation of different strength constitutive models or parameters and taking the experimentally measured disturbance data as convergence basis, and the established cylindrical RM instability disturbance growth material strength measurement experiment system and method have important significance for the strength research of materials under conditions of high pressure, high strain rate, large strain and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluid mechanics, in particular to a cylindrical RM instability perturbation growth material strength measurement experimental system and method thereof. BACKGROUND

[0002] The study of material dynamic strength under extreme conditions is a basic problem in the fields of fusion physics, material science, impact dynamics, etc. Especially in the study of armor protection, metal jet, inertial confinement fusion interface instability, celestial jet, etc., the material is in a state of complex stress, strain loading high pressure (several GPa to several hundred GPa, and in some cases even up to 1 TPa), high strain rate (10 5 / s-10 7 / s), large deformation (100% and above), which puts forward urgent needs for corresponding material dynamic strength data and strength measurement experimental techniques. Moreover, material strength is a physical quantity related to microstructure characteristics, loading state, and is influenced by multi-scale effects and multi-physical mechanism coupling. Limited by micro-macro cross-scale theory and physical model, the current experimental study of material strength is still the main means to obtain strength properties and calibrate theoretical models.

[0003] When the interface of different density substances is accelerated, the interface perturbation and instability caused by the light fluid pushing the heavy fluid is called Rayleigh-Taylor (RT) instability. When the shock wave passes through the interface of two fluids with different densities, the interface instability is Richtmyer-Meshkov (RM) instability. The instability perturbation growth method is an experimental method based on the inhibition characteristics of material strength on instability growth, which obtains material strength information by observing the development of perturbation under dynamic loading. Compared with other existing strength measurement methods in the high strain rate range, the perturbation growth method has the potential technical advantages of high loading pressure and wide strain range strength property research.

[0004] Currently, the RT perturbation growth method has been successfully applied to the measurement of material strength in planar and cylindrical configurations, but there are still some deficiencies in the RT instability perturbation growth method. The RT instability research is about the interface of light fluid and heavy fluid, and from the technical principle, it does not include the RM instability problem of interface perturbation when the shock wave passes from the heavy fluid to the light fluid. Therefore, the establishment of the cylindrical RM perturbation growth method strength measurement experimental system complements the existing strength measurement experimental techniques, provides a new technical method for the study of material dynamic strength under complex stress and strain loading, large strain, and high strain rate range, and has important significance for the measurement of material strength under extreme conditions such as high pressure, high strain rate, and large deformation. SUMMARY

[0005] The application aims to provide a cylindrical RM instability perturbation growth material strength measurement experimental system and method, to establish a cylindrical RM perturbation growth method for extreme condition material strength measurement, to complement existing strength measurement experimental techniques, and to provide a new technical method for dynamic strength research of materials in a complex stress, strain loading high pressure (several GPa to several hundred GPa, and even up to 1 TPa in some cases), high strain rate (10 5 / s-10 7 / s), and large deformation (100% and above) range.

[0006] The technical solution of the application to solve the above technical problems is as follows:

[0007] The application provides a cylindrical RM instability perturbation growth material strength measurement experimental system, comprising an experimental device and a measurement system.

[0008] The experimental device comprises a driving sleeve and a preset perturbation target, the driving sleeve is a hollow cylinder, and the preset perturbation target coaxially arranged in the driving sleeve is matched with the driving sleeve.

[0009] The preset perturbation target is a hollow cylinder, has a filling space in the preset perturbation target, and the filling space is filled with a filling medium.

[0010] Further, the outer diameter of the preset perturbation target is smaller than the inner diameter of the driving sleeve, the material, thickness, length, and speed of the driving sleeve are related to the impact loading state required by the experiment, and can be adjusted according to the experimental test requirements.

[0011] Further, the cylindrical RM instability perturbation growth material strength measurement experimental system has a preset perturbation interface with a single or multiple perturbation modes arranged uniformly or randomly along the inner wall of the preset perturbation target in the axial direction, the material of the preset perturbation target is the material to be tested for strength, and the thickness and length of the preset perturbation target are related to the impact loading state required by the experiment, and can be adjusted according to the experimental test requirements.

[0012] Further, the cylindrical RM instability perturbation growth material strength measurement experimental system has a sleeve implosion driving source outside the driving sleeve to realize cylindrical implosion of the driving sleeve through high-precision cylindrical loading, so as to realize cylindrical implosion impact loading on the preset perturbation target.

[0013] Further, the cylindrical RM instability perturbation growth material strength measurement experimental system has a measurement system to realize measurement of the perturbation growth speed of the perturbation interface and the perturbation interface morphology parameters, comprising a high-speed photography imaging device and a speed measurement probe, the high-speed photography imaging device is arranged above the end face of the driving sleeve, and the speed measurement probe is arranged in the filling space.

[0014] Further, the cylindrical RM instability disturbance growth material strength measurement experimental system, the high-speed photographic imaging equipment is arranged vertically above the end face of the driving sleeve, and the high-speed photographic imaging equipment adopts a visible light imaging mode, an X-ray imaging mode or a proton radiography imaging mode.

[0015] Further, the cylindrical RM instability disturbance growth material strength measurement experimental system, the velocity measurement probe is coaxially arranged in the filling space, and the light outlet of the velocity measurement probe faces the inner surface of the preset disturbance target.

[0016] Further, the cylindrical RM instability disturbance growth material strength measurement experimental system, the velocity measurement probe adopts a velocity measurement probe with a large light spot.

[0017] Further, the cylindrical RM instability disturbance growth material strength measurement experimental system, the velocity measurement probe adopts a laser interference velocity measurement probe with a large light spot.

[0018] The application further provides a cylindrical RM instability disturbance growth material strength measurement experimental method, which is based on the above cylindrical RM instability disturbance growth material strength measurement experimental system and comprises the following steps:

[0019] Coaxially arranging the preset disturbance target in the driving sleeve;

[0020] Vertically arranging the high-speed photographic imaging equipment on the end face of the driving sleeve, coaxially arranging the velocity measurement probe in the filling space and arranging the light outlet of the velocity measurement probe to face the inner surface of the preset disturbance target, and filling the filling medium in the preset disturbance target;

[0021] Starting the sleeve implosion driving source to load the driving sleeve to impact load the preset disturbance target;

[0022] Measuring the disturbance parameters by the high-speed photographic imaging equipment and the velocity measurement probe, and processing the disturbance growth data to obtain the material strength.

[0023] Compared with the prior art, the application has the following beneficial effects:

[0024] The cylindrical RM instability perturbation growth material strength measurement experiment system provided by the application utilizes the high-precision cylindrical impact loading transmission of the driving sleeve implosion to the preset perturbation target and the filling medium in the preset perturbation target, utilizes the measurement system to precisely measure the perturbation interface peak, bubble growth average speed and perturbation growth, obtains the strength data of the material at high strain rate and large strain through the data processing of comparison with the experimental value as the convergence basis, solves the problems of material dynamic strength measurement and physical model research under complex stress-strain loading, large strain and high strain rate, and the measurement of material dynamic strength by the cylindrical RM instability perturbation growth is a great supplement to the existing material dynamic strength measurement method under extreme loading conditions. 5 / s-10 7 / s).

[0025] The cylindrical RM instability perturbation growth material strength measurement experiment system provided by the application utilizes the driving sleeve and the preset perturbation target filled with the filling medium to perform the RM instability strength measurement, and expands the material strength measurement method in the interface perturbation instability problem of the shock wave from the heavy fluid to the light fluid.

[0026] The cylindrical RM instability perturbation growth material strength measurement experiment system provided by the application is beneficial to the experimental arrangement, test equipment and experiment when the filling medium is vacuum, that is, the specific target (metal / vacuum interface) structure of the perturbation growth method, and is convenient for high-precision experimental data acquisition. The cylindrical RM instability perturbation growth material strength measurement experiment system provided by the application utilizes the driving sleeve and the preset perturbation target filled with the filling medium, adopts the RM perturbation growth method, the obtained strength result is similar to the loading condition of the basic problem of micro-injection, micro-jet and other physical problems, and is beneficial to the establishment of the physical model meeting the actual application.

[0027] The cylindrical RM instability perturbation growth material strength measurement experiment system provided by the application has simple structure and convenient operation, can be used for material dynamic strength measurement under complex stress-strain loading, large strain and high strain rate, and lays a foundation for the research on the material strength, strength-perturbation parameter calibration relationship and cylindrical RM instability perturbation growth evolution law under the convergence loading large deformation and high strain rate. BRIEF DESCRIPTION OF DRAWINGS

[0028] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0029] Figure 1 The schematic diagram of the principle of the RM disturbance growth method of the application;

[0030] Figure 2 The structural schematic diagram of the cylindrical RM instability disturbance growth material strength measurement experimental system of the application.

[0031] The marks in the drawings and the corresponding names of parts:

[0032] In the drawings: 11 - driving sleeve, 12 - preset disturbance target, 13 - filling space, 14 - preset disturbance interface, 21 - high-speed photographic imaging device, 22 - velocity measurement probe. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the embodiments of the application clearer, the technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, rather than all the embodiments of the application. The components of the embodiments of the application described and shown in the drawings can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0035] Embodiment 1

[0036] When accelerated, the interface disturbance and instability caused by the light fluid pushing the heavy fluid at the interface of different density substances are called Rayleigh-Taylor (RT) instability. When the shock wave passes through the interface of two fluids with different densities, the interface instability is Richtmyer-Meshkov (RM) instability. The instability disturbance growth method is based on the inhibition characteristics of material strength on instability growth, and is an experimental method for obtaining material strength information by observing the development of disturbance under dynamic loading. Compared with other existing high strain rate range strength measurement methods, the disturbance growth method has the potential technical advantages of high loading pressure and wide strain range strength property research. For this reason, the cylindrical RM instability strength measurement method is based on the RM disturbance growth method, and the principle thereof will be explained as follows:

[0037] Please refer to Figure 1 ,Figure 1 The RM perturbation growth method (RM) principle is shown below: When an impact load, such as an explosive or flying fragment, is applied to a perturbation interface with a density gradient, the perturbation continues to grow. Within a short period of time, typical large-scale structures—bubbles and spikes—appear on the perturbation interface. The dynamic strength of the material can be determined by measuring the perturbation spikes, bubble growth rate, and perturbation morphology, and through subsequent data processing.

[0038] Based on the RM perturbation growth method, an embodiment of the present invention provides a cylindrical RM instability perturbation growth material strength measurement experimental system, which realizes material strength measurement under high pressure, high strain rate and large strain.

[0039] Please refer to Figure 2 An embodiment of the present invention provides an experimental system for measuring the strength of materials subjected to disturbance growth due to cylindrical RM instability, comprising: an experimental device and a measurement system, wherein a high-precision cylindrical impact load is transferred from the implosion of a driving sleeve 11 in the experimental device to a preset disturbance target 12 and a filling medium in the disturbance cylinder 12, and the measurement system is used to precisely measure the disturbance peak, the average bubble growth velocity, and the disturbance growth morphology, thereby enabling measurement of material strength under extreme conditions such as high pressure, high strain rate, and large deformation.

[0040] The experimental setup includes a drive sleeve 11 and a pre-set perturbation target 12. The drive sleeve 11 is a hollow cylinder. The pre-set perturbation target 12 is coaxially positioned within the drive sleeve 11, with its shape and dimensions matching the drive sleeve 11. The pre-set perturbation target 12 is longer than the target's length after being affected by the rarefaction waves at its two ends. The material, thickness, length, and speed of the drive sleeve 11 are related to the impact loading conditions required for the experiment and can be adjusted according to the test requirements.

[0041] The outside of the drive sleeve 11 is a sleeve implosion drive source, which realizes high-precision cylindrical implosion loading of the drive sleeve 11. In an embodiment of the present invention, the sleeve implosion drive source can be a high-current pulse power device, and the magnetic drive loading of the high-current pulse power device is used to realize high-precision cylindrical implosion loading of the drive sleeve 11. Magnetic drive cylindrical sleeve loading has the characteristics of easy control of the loading state, easy adjustment of the loading state and good loading uniformity, and has its unique advantages in the application of macroscopic sample cylindrical sleeve implosion loading. The sleeve implosion drive source can also use explosive loading, multi-channel laser driving, and X-ray radiation loading to realize cylindrical sleeve implosion. The drive sleeve 11 has a cylindrical structure, and the material of the drive sleeve 11 is selected from metal materials with good conductivity and ductility. The material of the drive sleeve 11 is preferably copper and aluminum, which have rich high-pressure physical properties and are easy to process.

[0042] The pre-disturbance target 12 is a hollow cylinder, and the shape and size of the pre-disturbance target 12 are matched with the driving sleeve 11. The material of the pre-disturbance target 12 is a material required to be tested for strength, and the thickness and length of the pre-disturbance target 12 are related to the impact loading state required by the experiment, and can be adjusted according to the experimental test requirements. The pre-disturbance target 12 has a filling space 13, and the filling space 13 is filled with a filling medium. The material of the filling medium is selected from materials that are easy to process and have known state equation and optical refractive index parameters, and the material of the filling medium is preferably vacuum, water, polystyrene, organic glass, quartz or LiF. When the material of the filling medium is vacuum, that is, the specific target (metal / vacuum interface) structure based on the RM disturbance growth method, it is beneficial to the experimental arrangement, the experiment and the acquisition of high-precision experimental data. The outer diameter of the pre-disturbance target 12 is smaller than the inner diameter of the driving sleeve 11, and different impact loading pressures and loading states can be adjusted by gap adjustment.

[0043] In a feasible embodiment, a plurality of pre-disturbance interfaces 14 of disturbance patterns are uniformly or randomly arranged along the inner wall of the pre-disturbance target 12. The plurality of pre-disturbance interfaces 14 are arranged on the inner wall of the pre-disturbance target 12, and the same experiment can be measured in different states, which not only improves the experimental efficiency, but also improves the experimental data accuracy through data checking between different disturbance growth patterns. Each pre-disturbance interface 14 can be composed of one or more minimum units. The shape of the pre-disturbance interface 14 can be a sine wave line, an arc, a hemisphere, etc., and the pre-disturbance interface 14 is preferably a sine wave line disturbance interface, which is convenient for numerical modeling and experimental analysis.

[0044] The measuring system is used to measure the disturbance interface disturbance growth rate and the disturbance interface topography parameters, and comprises a high-speed photography imaging device 21 and a velocity measurement probe 22. The high-speed photography imaging device 21 is arranged above the end face of the driving sleeve 11, and specifically, the high-speed photography imaging device 21 is arranged vertically above the end face of the driving sleeve 11. The high-speed photography imaging device 21 adopts visible light imaging, X-ray imaging or proton radiography imaging mode. When the filling medium in the filling space 13 is a visible light band transparent material, the high-speed photography imaging device 21 in the visible light wavelength range is used. When the filling space 13 is a visible light band opaque material, the X-ray imaging or proton radiography imaging device is used. The disturbance peak, the average bubble growth rate, the maximum amplitude of disturbance growth and the geometric configuration related parameters are obtained through disturbance growth data analysis. The high-speed photography imaging device 21 can be a high-speed photography imaging machine or a high-speed photography framing camera. The high-speed photography imaging machine is used to measure the disturbance growth and the interface topography. The high-speed photography framing camera is used to obtain the disturbance topography at different times when the filling medium is a transparent material. The disturbance peak, the average bubble growth rate, the maximum amplitude of disturbance growth and the geometric configuration related parameters are obtained through analysis.

[0045] The velocity measurement probe 22 is arranged in the filling space 13, and specifically, the velocity measurement probe 22 is coaxially arranged in the filling space 13. The filling medium is filled around the velocity measurement probe 22, and the light outlet of the velocity measurement probe 22 faces the inner surface of the preset disturbance target 12. The velocity measurement probe 22 is used to measure the interface velocity. After considering the apparent velocity refractive index correction, the disturbance peak growth rate, the bubble growth rate and the sleeve interface velocity history can be obtained. The large spot velocity measurement probe 22 is used for the interface of the preset disturbance target 12. The highest velocity and the lowest velocity curve in the velocity measurement spot of the preset disturbance target 12 are obtained by using the single-point multi-velocity spectrum measurement and analysis method. More specifically, the velocity measurement probe 22 adopts a laser interference velocity measurement probe with a large spot. The velocity measurement probe is connected with a laser velocity meter. The laser velocity meter is used to continuously measure the interface velocity. After considering the interface apparent velocity refractive index correction, the disturbance peak growth rate, the bubble growth rate and the sleeve interface velocity history can be obtained.

[0046] The cylindrical RM instability perturbation growth material strength measurement experimental system uses the driving sleeve 11 and the pre-set perturbation target 12 filled with filling medium, adopts the RM perturbation growth method, and has similar loading conditions to basic problems of physical problems such as micro-injection and micro-jet, and is beneficial to establish a physical model meeting actual application. The RM instability strength measurement is performed by using the driving sleeve 11 and the pre-set perturbation target 12 filled with filling medium, and the strength measurement method of the interface perturbation instability problem of the shock wave from the heavy fluid to the light fluid is expanded. The device has simple structure and convenient operation, and can be used for material dynamic strength measurement under complex stress-strain loading, large strain and high strain rate, is a great supplement to the existing material dynamic strength measurement method under extreme loading conditions such as high pressure, high strain rate and large deformation, and has important significance.

[0047] Embodiment 2

[0048] Please refer to Figure 1 and 2 The cylindrical RM instability perturbation growth material strength measurement experimental method of the embodiment comprises the following steps:

[0049] The pre-set perturbation target 12 is coaxially arranged in the driving sleeve 11; the high-speed photographic imaging device is arranged vertically to the end surface of the driving sleeve 11, the velocity measurement probe 22 is coaxially arranged in the filling space 13 and the light outlet is directed to the inner surface of the pre-set perturbation target 12, and the filling medium is filled in the pre-set perturbation target 12; the sleeve implosion driving source loads the driving sleeve to impact load the pre-set perturbation target 12, the perturbation parameters are measured by the high-speed photographic imaging device 21 and the velocity measurement probe 22, and the material strength is obtained by processing the perturbation growth data.

[0050] The high-precision cylindrical impact loading of the driving sleeve implosion is started, the perturbation growth and the interface morphology are measured by the high-speed photographic imaging device, and the interface velocity is measured by the velocity measurement probe, and the perturbation peak, the average speed of bubble growth, the maximum amplitude of perturbation growth and the related parameters of geometric configuration are obtained by analyzing the perturbation growth data. The velocity measurement probe with a large spot is used for the interface of the perturbation target, the single-point multi-speed spectrum measurement and analysis method is used, the highest speed and the lowest speed curve in the velocity measurement spot of the perturbation target are obtained. According to the RM target perturbation development law, the peak speed, the bubble speed, the perturbation stop growth position and the time point can be respectively confirmed. The strength of the material in the experiment is obtained by using different strength constitutive models or parameter fluid dynamics numerical simulation calculation, comparing the experimental measurement perturbation growth speed, amplitude and interface morphology data as convergence basis, and processing data.

[0051] The above detailed description of the specific implementation is further detailed for the purpose, technical solution and beneficial effect of the present application, and it should be understood that the above is only a specific implementation of the present application and is not used to limit the protection scope of the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A cylindrical RM instability disturbance growth material strength measurement experimental system, characterized by: include: experimental setup and measurement system; The experimental device comprises a driving sleeve (11) and a preset perturbation target (12), wherein the driving sleeve (11) is a hollow cylinder, and the preset perturbation target (12) adapted to match the driving sleeve (11) is coaxially arranged in the driving sleeve (11); The preset perturbation target (12) is a hollow cylinder, and a filling space (13) is provided in the preset perturbation target (12), and the filling space (13) is filled with a filling medium; A preset perturbation interface (14) having a single or multiple perturbation modes is uniformly or randomly provided along the inner wall of the preset perturbation target (12) in the axial direction. The preset perturbation target material is a material whose strength needs to be tested. The thickness and length of the preset perturbation target (12) are related to the impact loading state required by the experiment and can be adjusted according to the experimental test requirements. The driving sleeve (11) is provided with a sleeve implosion driving source outside thereof so as to realize cylindrical implosion impact loading of the preset disturbance target (12) by imploding the driving sleeve (11) through high-precision cylindrical loading; the measuring system is used to realize measurement of disturbance growth rate and disturbance interface morphology parameters of the disturbance interface, and includes a high-speed photography imaging device (21) and a velocity measuring probe (22); The speed measuring probe (22) is coaxially arranged in the filling space (13), and the light outlet of the speed measuring probe (22) faces the inner surface of the preset disturbance target (12).

2. The cylindrical RM instability disturbance growth material strength measurement experimental system according to claim 1 is characterized in that: The outer diameter of the preset perturbation target (12) is smaller than the inner diameter of the drive sleeve (11); the material, thickness, length, and speed of the drive sleeve (11) are related to the impact loading state required by the experiment and can be adjusted according to experimental test requirements.

3. The cylindrical RM instability disturbance growth material strength measurement experimental system according to claim 1 is characterized in that: The high-speed photography imaging device (21) is arranged above the end surface of the driving sleeve (11), and the speed measuring probe (22) is arranged in the filling space (13).

4. The cylindrical RM instability disturbance growth material strength measurement experimental system according to claim 3 is characterized in that: The high-speed photography imaging device (21) is vertically arranged above the end surface of the driving sleeve (11), and the high-speed photography imaging device (21) adopts visible light imaging, X-ray imaging or proton photography imaging.

5. The cylindrical RM instability disturbance growth material strength measurement experimental system according to claim 3 is characterized in that: The speed measuring probe (22) is a speed measuring probe with a large light spot.

6. The cylindrical RM instability disturbance growth material strength measurement experimental system according to claim 5 is characterized in that: The speed measuring probe (22) adopts a laser interference speed measuring probe with a large light spot.

7. An experimental method for measuring the strength of cylindrical RM instability disturbance growth materials, characterized in that: The cylindrical RM instability disturbance growth material strength measurement experimental system according to any one of claims 1 to 6 comprises the following steps: The preset disturbance target is coaxially arranged in the driving sleeve; The high-speed photography imaging device is arranged perpendicular to the end surface of the driving sleeve, the speed measuring probe is coaxially arranged in the filling space with the light outlet facing the inner surface of the preset disturbance target, and the preset disturbance target is fully filled with the filling medium; Starting the sleeve implosion drive source to load the drive sleeve to impact load the preset disturbance target; The disturbance parameters are obtained by measuring with high-speed imaging equipment and velocity probes, and the material strength is obtained by processing the disturbance growth data.

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