Multi-shock focusing point ignition promoting experimental device and experimental method

Abstract

The present application relates to the technical field of shock wave experiment, and discloses a multi-shock wave focusing ignition promoting experiment device and experiment method, the experiment device comprises a shock wave collision bin, a plurality of connecting ports are arranged on the side wall of the bin body, and different interval angles are arranged between the connecting ports; a shock wave tube unit, the shock wave tube unit comprises two or more double diaphragm shock wave tubes and a gas distribution assembly connected with the double diaphragm shock wave tubes; a data acquisition unit, the data acquisition unit comprises a photomultiplier tube, a plurality of pressure sensors, a constant current adapter electrically connected with the pressure sensors, and a data processing system electrically connected with the photomultiplier tube and the constant current adapter; compared with the traditional single shock wave single focusing ignition mode, the multi-angle shock wave is used for mutual coupling focusing ignition, not only the relationship between the shock wave of different incident angles and the shock wave focusing can be conveniently studied, but also the structure is simple, the operability is good, the repeatability is strong, the ignition efficiency is greatly improved, and the blank of multi-shock wave coupling ignition and experiment device is made up.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of shock wave experiment, in particular to a multi-shock wave focusing ignition promoting experiment device and experiment method. BACKGROUND

[0002] With the new concept engine into the hot stage, such as the detonation engine will be applied to the field of high-speed propulsion, but when the aircraft at high flight speed, due to the length of the aircraft combustion chamber is limited, the air stays in the combustion chamber is also very limited, only milliseconds or even microseconds of time. In milliseconds or even microseconds of time, how to realize the rapid and reliable ignition of fuel becomes the main problem. For the detonation engine initiation problem, the past researchers have proposed many methods: direct initiation method, adding detonation-strengthening additives to fuel, pre-detonation tube method, using solid obstacles to convert deflagration to detonation, using jet to convert deflagration to detonation. But all have corresponding shortcomings difficult to practical application.

[0003] The direct initiation method, such as using spark plug head to ignite fuel, has the most fatal shortcoming that the required ignition energy is large, and for some hydrocarbon fuels, the ignition energy is as high as several hundred kilojoules, which is difficult to meet the ignition condition. The biggest shortcoming of adding detonation-strengthening additives to fuel is that it needs to set up additional additive storage and supply device, which greatly increases the burden of the system. The pre-detonation tube method uses the detonation wave formed in the small size pre-detonation tube to form the detonation wave in the large size main detonation chamber, and its main shortcoming is poor stability. In some cases, the detonation wave in the pre-detonation tube may not be able to propagate stably, resulting in failure of initiation.

[0004] In actual engineering and experimental research, the method of deflagration to detonation is usually adopted. Deflagration is a subsonic propagation combustion wave, while detonation is an explosion wave that propagates in unreacted medium at supersonic speed, and detonation wave usually consists of a leading shock wave and a reaction zone following it, and can propagate stably with strong discontinuity. Using deflagration to detonation to obtain stable detonation is an important research direction to promote the development of detonation engine. There are mainly two ways of deflagration to detonation, one is to use solid obstacles such as baffle ring to induce detonation, and the main shortcoming is that it will cause the decrease of total pressure and the loss of power. The other is to use transverse fluid jet to induce detonation, but it also needs to set up a special fluid storage device, which increases the complexity of the system and the burden of the system.

[0005] With the deepening of people's understanding and research on the phenomenon of shock wave focusing, using shock wave focusing to induce detonation has become a new hot research direction. Shock wave is a compression wave in which pressure, density and temperature suddenly jump on the wave front in gas, liquid and solid medium, also called shock wave.

[0006] The existing research direction mainly focuses on the shock wave focusing phenomenon of single shock wave under different reflection surface conditions, and lacks the revelation of the shock wave focusing law and mechanism under the coupling of double shock waves or even multiple shock waves. SUMMARY

[0007] This section is intended to summarize some aspects of the embodiments of the present application and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract and title of the specification to avoid obscuring the purpose of this section, the abstract and the title, and such simplifications or omissions cannot be used to limit the scope of the present application.

[0008] In view of the above-mentioned existing lack of experimental devices for multi-shock wave focusing ignition promotion research, the present application is proposed.

[0009] Therefore, the purpose of the present application is to provide a multi-shock wave focusing ignition promotion experimental device, which is to build an experimental device to reveal the shock wave focusing law and mechanism under the coupling of double shock waves or even multiple shock waves.

[0010] To solve the above technical problems, the present application provides the following technical scheme: a multi-shock wave focusing ignition promotion experimental device, the experimental device comprising a shock wave collision bin, a shock wave tube unit and a data acquisition unit, wherein the shock wave collision bin is provided with a plurality of connection ports on the side wall of the bin body, and the connection ports have different interval angles; the shock wave tube unit is connected with each of the connection ports, and comprises a plurality of double membrane shock wave tubes and a gas distribution assembly connected with each of the double membrane shock wave tubes; and the data acquisition unit comprises a photomultiplier tube and a plurality of pressure sensors arranged in the side wall of the shock wave collision bin, a constant current adapter electrically connected with each of the pressure sensors, and a data processing system electrically connected with the photomultiplier tube and the constant current adapter.

[0011] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device of the present application, the aperture size of each of the connection ports is the same, and the central axis of each of the connection ports is in the same plane; the interval angle between each adjacent connection port is ~ degrees.

[0012] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device of the present application, the bin body side wall of the shock wave collision bin is further provided with a pressure gauge, and the pressure gauge can monitor the pressure in the shock wave collision bin.

[0013] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device, the double-membrane shock wave tube comprises a driving section, an intermediate section and a driven section connected in sequence, a first diaphragm is arranged at the connection between the driving section and the intermediate section, and a second diaphragm is arranged at the connection between the intermediate section and the driven section; and an end of the driving section away from the intermediate section is sealed, and an end of the driven section away from the intermediate section is connected with the connection port.

[0014] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device, a first pressure gauge is arranged in the wall of the driving section, a second pressure gauge and an exhaust pipeline are arranged in the wall of the intermediate section, and an electromagnetic valve is arranged in the exhaust pipeline.

[0015] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device, the gas distribution assembly comprises a gas distribution panel, a first gas pipe, a second gas pipe and a third gas pipe; the first gas pipe is connected between a first gas port of the gas distribution panel and the driving section; the second gas pipe is connected between a second gas port of the gas distribution panel and the intermediate section; and the third gas pipe is connected between a third gas port of the gas distribution panel and the shock wave collision chamber.

[0016] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device, the gas distribution panel is further provided with a mixed gas inlet, a high-pressure air inlet and a pump connection port; and a vacuum pump is connected to the pump connection port.

[0017] As a preferred scheme of the multi-shock wave focusing ignition promotion experimental device, each pressure sensor is arranged in the side wall around the plane of each connection port in the shock wave collision chamber, and can monitor the pressure in the shock wave collision chamber.

[0018] Another object of the present application is to provide a multi-shock wave focusing ignition promotion experimental method based on the above experimental device, so as to reveal the shock wave focusing law and mechanism under the coupling of double shock waves or even multiple shock waves.

[0019] To solve the above technical problems, the present application provides the following technical scheme: a multi-shock wave focusing ignition promotion experimental method based on the above multi-shock wave focusing ignition promotion experimental device, comprising the following operation steps:

[0020] S1: building the experimental device and initializing the state of the experimental device;

[0021] S2: operating the gas distribution panel, and respectively evacuating the air in the driving section, the intermediate section and the shock wave collision chamber by the vacuum pump; and after evacuation, closing the gas pipes connected between each driving section and intermediate section and the gas distribution panel;

[0022] S3: operating the gas distribution panel, filling the premixed gas into the shock collision chamber through each gas pipe, and filling the compressed air into the driving section and the intermediate section according to the preset strength of the shock wave;

[0023] S4: opening the electromagnetic valve in the exhaust pipeline, so that the intermediate section is depressurized, when the pressure difference between the driving section and the intermediate section is large enough, the first diaphragm and the second diaphragm are broken in turn, and the incident shock wave in the double-membrane shock tube propagates to the shock collision chamber;

[0024] S5: recording the pressure signal and the ignition time after the shock wave focusing in the shock collision chamber, and using the data processing system to analyze the experimental data.

[0025] As a preferred scheme of the multi-shock wave focusing ignition promotion experiment method, the pressure of the compressed air filled in the intermediate section is the average of the pressure of the driving section and the shock collision chamber.

[0026] The beneficial effects of the present application are:

[0027] Compared with the traditional single-shock single-set focusing ignition method, the multi-angle shock wave coupling focusing ignition is used, which not only facilitates the study of the relationship between the shock wave of different incident angles and the shock wave focusing, but also has the advantages of simple structure, good operability, strong repeatability, greatly improved ignition efficiency, and makes up for the blank of multi-shock coupling ignition and experimental device. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0029] Figure 1 It is the overall structure diagram of the multi-shock wave focusing ignition promotion experiment device of the present application.

[0030] Figure 2 It is the three-dimensional structure diagram of the connection between the shock collision chamber and the double-membrane shock tube of the multi-shock wave focusing ignition promotion experiment device of the present application.

[0031] Figure 3 It is the internal structure plane diagram of the shock collision chamber of the multi-shock wave focusing ignition promotion experiment device of the present application.

[0032] Figure 4 It is the connection diagram of the shock collision chamber and the shock tube unit of the multi-shock wave focusing ignition promotion experiment device of the present application.

[0033] Figure 5The schematic diagram of the running system of the multi-shock wave focusing point ignition promotion experimental device of the present application.

[0034] The reference signs in the drawings are shown as follows:

[0035] The shock wave collision chamber 100: connecting port 101, pressure gauge 102;

[0036] The shock wave tube unit 200: double-membrane shock wave tube 201, driving section 201a, first pressure gauge Y1, second pressure gauge Y2, exhaust pipeline P, electromagnetic valve F, intermediate section 201b, driven section 201c, first diaphragm 201d, second diaphragm 201e, gas distribution assembly 202, gas distribution panel 202a, first gas port 202a-1, second gas port 202a-2, third gas port 202a-3, mixed fuel gas inlet 202a-4, high-pressure air inlet 202a-5, pump machine connecting port 202a-6, first gas tube 202b, second gas tube 202c, third gas tube 202d, vacuum pump 202e;

[0037] The data acquisition unit 300: photomultiplier tube 301, pressure sensor 302, constant current adapter 303, data processing system 304. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objects, features and advantages of the present application more apparent and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0039] In the following description, a large number of specific details are set forth in order to facilitate a thorough understanding of the present application, but the present application can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without departing from the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0040] Secondly, the "one embodiment" or "embodiment" referred to herein means that the specific features, structures or characteristics can be included in at least one implementation of the present application. "In one embodiment" appearing in different places in the specification does not mean the same embodiment, nor is it an embodiment that is separate or alternative to other embodiments.

[0041] Thirdly, the present application is described in detail in conjunction with the schematic diagram, and in the detailed description of the embodiments of the present application, the cross-sectional view of the device structure is partially enlarged without the general proportion for the convenience of description, and the schematic diagram is only an example, which should not limit the scope of protection of the present application herein. In addition, three-dimensional spatial dimensions including length, width and depth should be included in actual manufacturing.

[0042] Embodiment 1

[0043] Reference Figures 1-5For the first embodiment of the present application, a multi-shock wave focusing ignition promotion experimental device is provided, which comprises a shock wave collision chamber 100, a shock wave tube unit 200 and a data acquisition unit 300, wherein the shock wave collision chamber 100 is used to provide a collision space for double shock waves or multiple shock waves; the shock wave tube unit 200 is used to generate the shock waves required by the experiment, is connected with the shock wave collision chamber 100, and enables the shock waves to enter the collision chamber; and the data acquisition unit 300 is used to acquire ignition data and pressure data of the shock wave collision focusing process, so as to facilitate the later experimental analysis.

[0044] Specifically, the shock wave collision chamber 100 has a regular shape as a whole, preferably a cubic structure, a plurality of connecting ports 101 are arranged on the side wall of the chamber body, and the connecting ports 101 have different interval angles; wherein the connecting port 101 connects the inside and outside of the shock wave collision chamber 100; the aperture sizes of the connecting ports 101 are the same, and the central axes of the connecting ports 101 are all in the same plane; the interval angles between the adjacent connecting ports 101 are 0-180 degrees, so that the shock waves can be collected and collided in the shock wave collision chamber 100; it should be noted that the interval angles of the connecting ports 101 are preferably 60 degrees.

[0045] Further, a pressure gauge 102 is arranged in the side wall of the chamber body of the shock wave collision chamber 100, and the pressure in the shock wave collision chamber 100 is monitored through the pressure gauge 102.

[0046] The shock wave tube unit 200 is connected with the connecting ports 101 of the shock wave collision chamber 100, and comprises a plurality of double-membrane shock wave tubes 201 and a gas distribution assembly 202 connected with the double-membrane shock wave tubes 201; wherein the double-membrane shock wave tube 201 is a connecting pipeline for generating shock waves; and the gas distribution assembly 202 is a gas distribution system for generating shock waves. In this scheme, two shock wave tubes with the same structure are taken as an example for description.

[0047] Specifically, the double-membrane shock wave tube 201 is composed of three sections of rigid pipelines, which are a driving section 201a, an intermediate section 201b and a driven section 201c connected in sequence, a first diaphragm 201d is arranged at the connection between the driving section 201a and the intermediate section 201b, and a second diaphragm 201e is arranged at the connection between the intermediate section 201b and the driven section 201c; one end of the driving section 201a away from the intermediate section 201b is sealed; and one end of the driven section 201c away from the intermediate section 201b is connected with the connecting port 101.

[0048] Further, the lengths of the driving section 201a and the intermediate section 201b can be changed, and the size of the intermediate section 201b is generally small; unlike the existing shock tube, the feature of the present scheme is not the ratio of the driving section 201a to the driven section 201c, but whether the shock waves can collide at the same point in the shock collision chamber 100 at the same speed.

[0049] It should be further noted that the connecting ends of each tube section are flange-connected, and a groove for accommodating a rubber gasket is arranged on the flange surface, so that the double-membrane shock tube 201 has good air tightness.

[0050] Further, a first pressure gauge Y1 is arranged in the wall of the driving section 201a, a second pressure gauge Y2 and an exhaust pipeline P are arranged in the wall of the intermediate section 201b, and an electromagnetic valve F is arranged in the exhaust pipeline P. The first pressure gauge Y1 is used to observe the pressure in the driving section 201a, and the second pressure gauge Y2 is used to observe the pressure in the intermediate section 201b; the electromagnetic valve F is used to control the opening and closing of the exhaust pipeline P, so as to realize the rapid exhaust of the gas in the intermediate section 201b.

[0051] The gas distribution assembly 202 includes a gas distribution panel 202a, a first gas pipe 202b, a second gas pipe 202c, and a third gas pipe 202d; the first gas pipe 202b is connected between the first gas port 202a-1 of the gas distribution panel 202a and the driving section 201a; the second gas pipe 202c is connected between the second gas port 202a-2 of the gas distribution panel 202a and the intermediate section 201b; and the third gas pipe 202d is connected between the third gas port 202a-3 of the gas distribution panel 202a and the shock collision chamber 100.

[0052] The gas distribution panel 202a is a control panel formed by a gas distribution system, and an existing gas distribution system can be used, and the specific structure is not described in detail. The first gas pipe 202b, the second gas pipe 202c, and the third gas pipe 202d are soft pipelines for gas extraction and gas transmission, which are connected with the gas distribution panel 202a to realize the gas control of the driving section 201a, the intermediate section 201b, and the shock collision chamber 100.

[0053] The gas distribution panel 202a further comprises a mixed fuel gas inlet 202a-4, a high-pressure air inlet 202a-5, and a pump connection port 202a-6; and the pump connection port 202a-6 is connected with a vacuum pump 202e. The mixed fuel gas inlet 202a-4 is used to input premixed fuel gas; the high-pressure air inlet 202a-5 is used to input compressed high-pressure air; it should be noted that high-pressure air is selected as the driving gas because it is mainly used in high-speed aircraft; and the vacuum pump 202e is used to extract the air and the combustion products after the experiment in the double-membrane shock tube 201 and the shock collision chamber 100.

[0054] A data acquisition unit 300, comprising a photomultiplier tube 301 and a plurality of pressure sensors 302 arranged in the sidewall of the shock collision chamber 100, a constant current adapter 303 electrically connected with each pressure sensor 302, and a data processing system 304 electrically connected with the photomultiplier tube 301 and the constant current adapter 303.

[0055] The photomultiplier tube 301 is installed in the sidewall of the shock collision chamber 100 at any position, for monitoring the ignition time at the moment of shock collision, and its accuracy is better than that of the conventional schlieren measurement method. Each pressure sensor 302 is arranged in the sidewall of the shock collision chamber 100 at the plane where each connecting port 101 is located, and can monitor the pressure in the shock collision chamber 100; it should be noted that at least one pressure sensor 302 is installed in each sidewall of the shock collision chamber 100, and through the synchronous monitoring of each pressure sensor 302, the pressure distribution in the shock collision chamber 100 after the shock collision is obtained.

[0056] Each pressure sensor 302 is electrically connected with the constant current adapter 303, and is connected with the data processing system 304 through the constant current adapter 303. The constant current adapter 303 processes the experimental signal, reduces noise or performs gain, so that it is more obvious in the data acquisition system. When a shock wave passes through to produce pressure change, the time of change and the values before and after the pressure change will be recorded by the data processing system 304.

[0057] Embodiment 2

[0058] Reference Figure 5 As a second embodiment of the present application, the embodiment provides a multi-shock wave focusing ignition promotion experiment method, based on the multi-shock wave focusing ignition promotion experiment device of the above-mentioned embodiment 1, further comprising the following operation steps:

[0059] S1: building the experiment device and initializing the state of the experiment device;

[0060] According to the composition of the experiment device, the assembly is carried out, and the connection integrity, pipeline airtightness and the like of the experiment device are detected and ensured to be good. Among them, the thickness selection of the first diaphragm 201d and the second diaphragm 201e is comprehensively determined by the type of the passive experimental gas, the target five-zone temperature of the experiment, the target five-zone pressure, the initial temperature of the shock wave tube and the shock wave attenuation coefficient. The two diaphragms with appropriate thickness are installed between the driving section 201a and the intermediate section 201b.

[0061] S2: operating the gas distribution panel 202a, and respectively evacuating the air in the driving section 201a, the intermediate section 201b and the shock collision chamber 100 by the vacuum pump 202e, and closing the air pipes connected between each driving section 201a and intermediate section 201b and the gas distribution panel 202a after evacuation;

[0062] Specifically, by opening the gas distribution panel 202a, the air in each tube section of the double membrane shock tube 201 and the shock collision chamber 100 is first pumped out by the vacuum pump 202e, and then each gas tube is closed, so that the experimental device maintains a low-pressure pure environment.

[0063] S3: Operate the gas distribution panel 202a to fill premixed fuel gas into the shock collision chamber 100 through each gas tube, and fill compressed air into the driving section 201a and the intermediate section 201b according to the preset strength of the shock wave.

[0064] By controlling the gas distribution panel 202a, each gas tube is used to inject experimental gas into the shock collision chamber 100, the driving section 201a and the intermediate section 201b, respectively. The premixed fuel gas is injected into the shock collision chamber 100, and the compressed air is injected into the driving section 201a and the intermediate section 201b. It should be noted that the pressure of the filled compressed air is determined according to the required strength of the shock wave.

[0065] Further, the pressure of the compressed air filled in the intermediate section 201b is the average of the pressure of the compressed air filled in the driving section 201a and the shock collision chamber 100.

[0066] S4: Open the electromagnetic valve F in the exhaust pipeline P to release the pressure in the intermediate section 201b. When the pressure difference between the driving section 201a and the intermediate section 201b is large enough, the first diaphragm 201d and the second diaphragm 201e will break in turn, and the incident shock wave propagating to the shock collision chamber 100 will be generated in the double membrane shock tube 201.

[0067] After filling the gas into each tube section of the double membrane shock tube 201 and the shock collision chamber 100, each connecting gas tube is closed. The electromagnetic valve F is opened to exhaust the gas in the intermediate section 201b, and the intermediate section 201b is connected to the atmosphere to complete the pressure relief. The pressure difference between the intermediate section 201b and the shock collision chamber 100 will be large. When the pressure difference is large enough, the first diaphragm 201d between the driving section 201a and the intermediate section 201b will break, and at the moment of breaking, the second diaphragm 201e between the intermediate section 201b and the driven section 201c will break, thereby generating an incident shock wave propagating to the shock collision chamber 100.

[0068] S5: Record the pressure signal and ignition time after shock focusing in the shock collision chamber 100, and use the data processing system 304 to analyze the experimental data.

[0069] When the incident shock wave enters the shock wave collision chamber 100, the pressure sensor 302 installed on each wall records the pressure signal after the shock wave focusing due to the propagation of the incident shock wave to the reflection surface; using the collected pressure signal data, the shock wave reflection focusing pressure signal diagram can be obtained, and the change of the wave system after the shock wave focusing can be observed. Finally, the experimental conclusion can be obtained according to the experimental results.

[0070] Example 1

[0071] According to the experimental device and experimental method in examples 1 and 2, the experimental operation is carried out, which specifically includes the following process:

[0072] S1: build the experimental device and initialize the state of the experimental device;

[0073] In the experimental device, the material of the shock wave collision chamber 100 is stainless steel and quartz sheet, wherein the stainless steel forms the frame around, and the quartz sheet is located on the opposite two sides, which is transparent, so that the shock wave collision change inside the chamber can be easily observed. Its size is: length 0.31757m, width 0.15m, height 0.30938m. A plurality of connecting ports 101 are respectively arranged on the side walls of the frame of the shock wave collision chamber 100, and the angles between the connecting ports 101 are 30°, 90°, 120° and 180°.

[0074] The double membrane shock wave tube 201 is provided with two structures, which are connected with different two connecting ports 101 on the shock wave collision chamber 100 respectively; the material of the double membrane shock wave tube 201 is stainless steel, which is a circular pipe with a length of 1.2m and an inner diameter of 30mm, wherein the driving section 201a is 1m, the middle section 201b is 0.1m, and the driven section 201c is 0.1m; the connecting end of each pipe section is connected by special flange, and a groove with a diameter of 70mm and a depth of 4mm is arranged on the disc surface of the flange, and a rubber gasket is installed in the groove.

[0075] In this example, the electromagnetic valve F is a BS22A electromagnetic valve of Shanghai Bangsong Company, with a nominal pressure of 5MPa, a nominal diameter of 6mm, a medium temperature of 90K, and a 24V DC power supply.

[0076] The first diaphragm 201d and the second diaphragm 201e are PET films, and the thickness is determined by the type of the driven experimental gas, the target five-zone temperature, the target five-zone pressure, the initial temperature of the shock wave tube and the shock wave attenuation coefficient.

[0077] The data processing system 304 is MR6000 of Japan Rikasei Company, which has 8 channels and a sampling frequency of 200M sample / s; the data acquisition system is connected with the constant current adapter through the BCN line to obtain the pressure signal. The data acquisition system is connected with the computer, and the experimental data can be automatically uploaded and saved into the computer each time.

[0078] For the driven gas, the driven gas selected in the experiment is hydrogen premixed gas, and a shock wave with a five-zone pressure of 4 bar and a five-zone temperature of 1200K is generated. According to the calculation of the shock tube and the detonation toolbox of California Institute of Technology, the speed of the incident shock wave is 817.6m / s. The shock collision chamber 100 is filled with 0.4357 bar of hydrogen premixed gas, the driving section 201a is 8.7 bar of compressed air as the driving gas, and the middle section 201b is 4.5 bar of high-pressure air.

[0079] S2: Operate the gas distribution panel 202a, and respectively evacuate the driving section 201a, the middle section 201b in the two shock tubes, and the air in the shock collision chamber 100 through the vacuum pump 202e. After evacuation, close the air pipes connected between the driving section 201a and the middle section 201b and the gas distribution panel 202a;

[0080] S3: Operate the gas distribution panel 202a again, fill the hydrogen premixed gas into the shock collision chamber 100 through the air pipes, and fill the compressed air with different pressures into the driving section 201a and the middle section 201b according to the preset intensity of the shock wave;

[0081] S4: Open the electromagnetic valve F in the exhaust pipe P to make the middle section 201b depressurize. When the pressure difference between the driving section 201a and the middle section 201b is large enough, the first diaphragm 201d and the second diaphragm 201e are broken in turn, and the incident shock wave propagating to the shock collision chamber 100 is generated in the double-membrane shock tube 201;

[0082] S5: Record the pressure signal and ignition time in the shock collision chamber 100 after the shock wave focusing, and analyze the experimental data by using the data processing system 304.

[0083] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present application but not limit the present application. Although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present application can be modified or replaced equivalently without departing from the spirit and scope of the present application, and all of them should be covered in the scope of the claims of the present application.

Claims

1. A multi-shock focusing point initiation facilitation experimental device, characterized by: include, The shock wave impact chamber (100) has several connection ports (101) on its side wall. Each connection port (101) has a different spacing angle, and the central axis of each connection port (101) is in the same plane. A shock tube unit (200), connected to each of the aforementioned connection ports (101), includes at least two double-membrane shock tubes (201) and a gas distribution assembly (202) connected to each of the aforementioned double-membrane shock tubes (201); and, The data acquisition unit (300) includes a photomultiplier tube (301) and several pressure sensors (302) disposed in the side wall of the shock wave collision chamber (100), a constant current adapter (303) electrically connected to each of the pressure sensors (302), and a data processing system (304) electrically connected to the photomultiplier tube (301) and the constant current adapter (303).

2. The multi-shockwave focused ignition facilitating experimental apparatus of claim 1, wherein: The aperture size of each of the aforementioned connection ports (101) is the same; The angle between each adjacent connection port (101) is between 0 and 180 degrees.

3. The multi-shockwave focused ignition facilitating experimental apparatus according to claim 2, characterized by: A pressure gauge (102) is also installed in the side wall of the shock wave impact chamber (100), which can monitor the pressure inside the shock wave impact chamber (100).

4. The multi-shockwave focused ignition facilitating experimental apparatus of claim 3, wherein: The dual-membrane shock tube (201) includes a driving section (201a), an intermediate section (201b), and a driven section (201c) connected in sequence. A first diaphragm (201d) is provided at the connection between the driving section (201a) and the intermediate section (201b), and a second diaphragm (201e) is provided at the connection between the intermediate section (201b) and the driven section (201c). The end of the drive section (201a) away from the intermediate section (201b) is blocked; The end of the driven segment (201c) away from the intermediate segment (201b) is connected to the connection port (101).

5. The multi-shockwave focused ignition facilitating experimental apparatus of claim 4, wherein: The drive section (201a) is equipped with a first pressure gauge (Y1) in its pipe wall, the intermediate section (201b) is equipped with a second pressure gauge (Y2) and an exhaust pipe (P) in its pipe wall, and the exhaust pipe (P) is equipped with a solenoid valve (F).

6. The multi-shockwave focused ignition facilitating experimental apparatus of claim 5, wherein: The gas distribution assembly (202) includes a gas distribution panel (202a), a first gas pipe (202b), a second gas pipe (202c) and a third gas pipe (202d); The first air pipe (202b) is connected between the first air port (202a-1) and the drive section (201a) of the air distribution panel (202a); the second air pipe (202c) is connected between the second air port (202a-2) and the intermediate section (201b) of the air distribution panel (202a); and the third air pipe (202d) is connected between the third air port (202a-3) of the air distribution panel (202a) and the shock wave impact chamber (100).

7. The multi-shockwave focused ignition facilitating experimental apparatus of claim 6, wherein: The gas distribution panel (202a) is also provided with a mixed gas inlet (202a-4), a high-pressure air inlet (202a-5), and a pump connection port (202a-6). The pump connection port (202a-6) is connected with a vacuum pump (202e).

8. The multi-shockwave focused ignition facilitating experimental apparatus of claim 7, wherein: Each pressure sensor (302) is arranged in the sidewall of the plane where each connection port (101) of the shock wave collision chamber (100) is located, and can monitor the pressure inside the shock wave collision chamber (100).

9. A multi-shockwave focused point initiation facilitation experimental method, characterized by: The multi-shock wave focusing ignition promoting experimental device according to any one of claims 6-8 further comprises the following operation steps: Building an experimental device and initializing the state of the experimental device; Operating the gas distribution panel (202a) to evacuate the air in the driving section (201a), the intermediate section (201b) and the shock wave collision chamber (100) by the vacuum pump (202e), and closing the gas pipes connected between each driving section (201a) and intermediate section (201b) and the gas distribution panel (202a) after evacuation; Operating the gas distribution panel (202a) to fill the premixed gas into the shock wave collision chamber (100) through the gas pipes, and filling the compressed air into the driving section (201a) and the intermediate section (201b) according to the preset intensity of the shock wave; Opening the electromagnetic valve (F) in the exhaust pipeline (P) to make the intermediate section (201b) depressurize, and when the pressure difference between the driving section (201a) and the intermediate section (201b) is large enough, the first diaphragm (201d) and the second diaphragm (201e) break in turn, and the incident shock wave generated in the double diaphragm shock tube (201) propagates to the shock wave collision chamber (100); Recording the pressure signal and ignition time in the shock wave collision chamber (100) after shock wave focusing, and analyzing the experimental data by using the data processing system (304).

10. The multi-shockwave focused point ignition promoting experimental method of claim 9, wherein: The pressure of the compressed air filled in the intermediate section (201b) is the average of the pressure of the driving section (201a) and the shock wave collision chamber (100).

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