Rigid support ring for ignition wire in coaxial cylindrical deflagration drive device

Abstract

This invention discloses a rigid support ring for an ignition wire in a coaxial cylindrical deflagration drive device, comprising a rotating handle, a threaded cap, and a rigid support rod. The rotating handle includes a first handle portion and a second handle portion, and the rigid support rod is located within the deflagration drive section. The rigid support rod has a fork, which includes a first fork portion, a first fork segment, and a second fork segment. The root of the first fork portion is on the same horizontal plane as the axis centerline of the deflagration drive section. The first fork portion is V-shaped. The maximum distance between the first fork segment and the second fork segment is less than the diameter of the mounting hole on the deflagration drive section. A sealing element is fitted at the junction between the first handle portion and the second handle portion, and a sealing ring is fitted on the contact surface between the sealing element and the deflagration drive section. The rigid support rod is made of plastic. By supporting the ignition wire through the first fork portion on the rigid support rod, excessive drooping of the ignition wire between the two electrodes, exceeding the allowable range of coaxiality, can be prevented.

Description

Technical Field

[0001] This invention relates to the technical field of experimental research on high-temperature high-speed gas dynamics, high-speed aircraft, etc., and more specifically, to a rigid support ring for an ignition wire in a coaxial cylindrical deflagration drive device. Background Technology

[0002] A shock tube / wind tunnel is an experimental device widely used in fields such as high-temperature, high-speed gas dynamics and high-speed aircraft. Its basic principle is that high-pressure driving gas compresses low-pressure test gas through a shock wave, bringing it to the required experimental state. For example... Figure 1 As shown, a typical shock tube / wind tunnel includes a drive section 1', a driven section 2', a nozzle 3', and a test section 4'. Before the test, the drive section 1' and the driven section 2' are separated by a diaphragm 5'. High-pressure drive gas is filled into the drive section 1', and low-pressure test gas is filled into the driven section 2'. During the test, the diaphragm 5' ruptures, the high-pressure gas expands and enters the driven section 2', and a rapidly moving shock wave is generated in the driven section 2'. If the gas after the shock wave is used directly for the test, the equipment operates in shock tube mode; if the test gas accelerated by the nozzle 3' is used for the test, the equipment operates in shock tunnel mode.

[0003] The total temperature and total pressure range of the test gas are key indicators of equipment capability, both of which depend on the driving capability of the high-pressure driving gas. Room temperature, high-pressure gases can no longer meet increasingly demanding testing requirements. Therefore, three high-performance driving technologies have been developed both domestically and internationally: piston-driven, heated light gas-driven, and detonation-driven. Among these, detonation-driven technology is characterized by low cost, simple structure, and relatively high safety, and is currently the mainstream technology in China.

[0004] The detonation-driven shock tube was first proposed by Bird in 1957. In 1981, Mr. Yu Hongru of the Institute of Mechanics, Chinese Academy of Sciences, built a 13.3m long detonation-driven shock tube, which was put into use in 1983. In 1994, the Institute of Mechanics, Chinese Academy of Sciences, developed the JF-10 detonation-driven high-enthalpy shock tunnel [see Yu Hongru, Zhao Wei, and Yuan Shengxue, Performance of Hydrogen-Oxygen Detonation-Driven Shock Tunnel - Aerodynamic Testing and Measurement Control, 1993, 7(3): 38-42]. With the help of Mr. Yu Hongru, Gronig et al. built a high-enthalpy shock tunnel (TH2-D) using reverse detonation drive at RWTH Aachen University in Germany in 1993. In 1994, NASA modified the original free piston drive design and built the Hypulse wind tunnel at GASL. This wind tunnel can operate in both reflected shock tunnel mode and expansion tube mode. [See ChueRSM, Tsai CY, Bakos RJ, Erdos JI, Rogers RC (2002) NASA's Hypulse Facility at GASL - Dual Mode, Dual Driver Reflected-Shock / Expansion Tunnel. In: Lu F, Marren D (eds), Advanced Hypersonic Test Facilities, Progress in Astronautics and Aeronautics, Vol. 198, AIAA, Chapter 3, pp29-71].

[0005] Detonation-driven systems require the formation of an axially propagating detonation wave within the drive section. The non-uniform flow field following the detonation wave leads to the following problems with this drive technology: First, the range of detonable gas mixing ratios is much narrower than that of combustible systems, and the range of temperature and sound velocity of the drive gas is also correspondingly narrower, thus limiting the total temperature range of the test gas that detonation-driven systems can provide; Second, the effective drive pressure provided by detonation-driven systems does not exceed 40% of the equipment's pressure limit, thus limiting the total pressure range of the test gas.

[0006] Due to the aforementioned problems with detonation-driven systems, it is necessary to overcome these issues by introducing coaxial cylindrical deflagration-driven technology. However, this technology requires high-voltage electrodes to be inserted at both ends of the drive section, with an ignition wire running along the centerline of the drive section between the two electrodes. But shock tubes / shock tunnels are pulsed experimental devices with effective experimental times on the order of milliseconds, approximately proportional to the length of the shock tube / shock tunnel. To obtain longer experimental times, the pipe length needs to be increased; for example, the JF-12 shock tunnel at the Institute of Mechanics, Chinese Academy of Sciences, is over 200 meters long. In large-scale deflagration-driven shock tubes / shock tunnels, to prevent the ignition wire from drooping excessively between the two electrodes, exceeding the allowable range of coaxiality, support needs to be provided in the middle of the ignition wire. This support structure must simultaneously meet the following requirements: 1. Ensure airtightness and withstand high pressure; 2. Ensure insulation and prevent local breakdown.

[0007] Existing document 1 (CN201058067) discloses a support for filling a hot water bottle, which includes a tiger-mouth-shaped support ring fixed to the handle via a support rod. An elastic hanging ring is provided at the end of the handle. When in use, the elastic hanging ring is opened and removed from the neck of the hot water bottle. The handle is held and the tiger-mouth-shaped support ring is placed in the neck of the hot water bottle. However, this solution belongs to the field of daily necessities and cannot meet the requirements of the above-mentioned support structure.

[0008] Existing document 2 (CN102407947A) discloses a shock tunnel detonation dual-drive device, comprising: a shock tunnel having a detonation drive section, one end of which is provided with a detonation unloading section, and the other end with a driven section; a first diaphragm is provided between the detonation unloading section and the detonation drive section, and a second diaphragm is provided between the driven section and the detonation drive section; a forward detonation drive ignition device is provided in the section of the detonation drive section near the detonation unloading section, and a reverse detonation drive ignition device is provided in the section of the detonation drive section near the driven section; a controllable delay trigger is connected between the forward detonation drive ignition device and the reverse detonation drive ignition device. The apparatus and method are as follows: 1) A forward detonation ignition device is installed at one end of the detonation driving section of the shock tunnel near the detonation unloading section, and a reverse detonation driving ignition device is installed at one end of the detonation driving section near the driven section; 2) Ignition is performed by the forward detonation ignition device to form a forward driving detonation wave; 3) After the forward detonation wave has propagated along the detonation driving section for a predetermined time, it is ignited by the reverse detonation driving ignition device to form a reverse driving detonation wave; 4) The reverse driving detonation wave tears the diaphragm set between the driven section and the detonation driving section, and the forward detonation wave and the reverse detonation wave intersect to form a moving shock wave, which enters the driven section to compress the test gas in the driven section.

[0009] To meet the requirements of coaxial cylindrical deflagration drive technology, this invention proposes a rigid support ring for the ignition wire of a coaxial cylindrical deflagration drive device, and this rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device is not easily conceived by those skilled in the art. Summary of the Invention

[0010] In view of this, the present invention provides a rigid support ring for an ignition wire of a coaxial cylindrical deflagration drive device, comprising: a rotating handle, a threaded cap, and a rigid support rod;

[0011] The rotary handle is inserted into the deflagration drive section, and the rotary handle is connected to the deflagration drive section through the threaded cap;

[0012] The rotary handle includes a first handle portion and a second handle portion connected to the first handle portion. The diameter of the first handle portion is smaller than the diameter of the second handle portion. The end of the second handle portion away from the first handle portion is connected to the rigid support rod. The rigid support rod is located within the deflagration drive section.

[0013] The rigid support rod is provided with a fork at the end away from the second handle. The fork includes a first fork portion, which is located on the side close to the second handle. The first fork portion includes a first fork segment and a second fork segment connected to the first fork segment. The root of the first fork portion is on the same horizontal plane as the axis centerline of the combustion drive section, and the root of the first fork portion faces the side of the second handle.

[0014] The first forked portion is V-shaped;

[0015] The maximum distance between the first forked section and the second forked section is less than the diameter of the mounting hole on the deflagration drive section;

[0016] A sealing element is fitted at the junction between the first handle part and the second handle part, and a sealing ring is fitted on the contact surface between the sealing element and the deflagration drive section.

[0017] The rigid support rod is made of plastic.

[0018] Optionally, the fork further includes a second fork connected to the first fork portion. The second fork portion is located on the side away from the second handle portion. The second fork portion includes a third fork segment and a fourth fork segment. The end of the third fork segment near the second handle portion is connected to the end of the first fork segment away from the second handle portion. The end of the fourth fork segment near the second handle portion is connected to the end of the second fork segment away from the second handle portion.

[0019] The angle between the first forked segment and the third forked segment, and the angle between the second forked segment and the fourth forked segment are both α1, where 90° > α1 < 180°, and the extension of the third forked segment does not intersect the extension of the fourth forked segment; or, the angle between the first forked segment and the third forked segment, and the angle between the second forked segment and the fourth forked segment are both α2, where 45° ≥ α2 ≤ 90°, and the extension of the third forked segment intersects the extension of the fourth forked segment.

[0020] Optionally, the interface between the first forked segment and the third forked segment is the first interface, and the interface between the second forked segment and the fourth forked segment is the second interface. The distance between the first interface and the second interface is less than the diameter of the mounting hole on the deflagration drive segment.

[0021] Optionally, the second handle portion is connected to the rigid support rod by a thread.

[0022] Optionally, the first handle portion, the second handle portion, and the seal are integrally formed.

[0023] Optionally, the seal is a sealing ring.

[0024] Optionally, along the first direction, the length of the handle is 20cm-40cm, and the first direction is the direction from the first handle portion to the second handle portion.

[0025] Compared with the prior art, the rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device provided by the present invention achieves at least the following beneficial effects:

[0026] First, by aligning the root of the first fork on the rigid support rod with the center line of the detonation drive section on the same horizontal plane, the ignition wire can be supported by the first fork on the rigid support rod, preventing the ignition wire from drooping excessively between the two electrodes and exceeding the allowable range of coaxiality. It should be noted that the detonation drive technology requires two electrodes to be inserted at both ends of the detonation drive section, and an ignition wire is arranged between the two electrodes along the axis of the detonation drive section.

[0027] Secondly, by rotating the seal on the handle, and by fitting a sealing ring on the contact surface between the seal and the deflagration drive section, the airtightness of the deflagration drive section can be ensured, and it can withstand high air pressure.

[0028] Third, by using a plastic material with good insulation for the rigid support rod, the insulation between the rigid support rod and the rotating handle can be guaranteed, avoiding localized breakdown.

[0029] Of course, any product implementing this invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0030] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0031] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0032] Figure 1 This is a schematic diagram of a shock tube / wind tunnel provided in the prior art;

[0033] Figure 2 This is a front view of an ignition wire rigid support ring for a coaxial cylindrical deflagration drive device provided in an embodiment of the present invention;

[0034] Figure 3 This is a front view of another rigid support ring for an ignition wire in a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention;

[0035] Figure 4 This is a side view of an ignition wire rigid support ring for a coaxial cylindrical deflagration drive device provided in an embodiment of the present invention;

[0036] Figure 5 yes Figure 4 A cross-sectional view of one type of AA;

[0037] Figure 6 yes Figure 4 Another type of AA cross-sectional diagram;

[0038] Figure 7 This is a cross-sectional view of a rotary handle and a rigid support rod assembled according to an embodiment of the present invention;

[0039] Figure 8 This is a cross-sectional view of another embodiment of the present invention after the rotary handle and rigid support rod are assembled;

[0040] Figure 9 This is a schematic diagram of the structure of the middle section of the deflagration-driven section provided in an embodiment of the present invention;

[0041] Figure 10 This is a schematic diagram of the structure of a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel provided in an embodiment of the present invention;

[0042] Figure 11 yes Figure 10 Enlarged view of the structure at point B in the middle;

[0043] Figure 12 yes Figure 10 Enlarged view of the structure of the intermediate discharge system;

[0044] Figure 13 This is a logic block diagram of a discharge system provided in an embodiment of the present invention;

[0045] Figure 14 This is a schematic diagram of a shock tube / wind tunnel provided in an embodiment of the present invention. Detailed Implementation

[0046] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0047] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0048] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0049] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0050] It should be noted that similar labels and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be discussed further in subsequent figures.

[0051] Figure 2 This is a front view of an ignition wire rigid support ring for a coaxial cylindrical deflagration drive device provided in an embodiment of the present invention; Figure 3 This is a front view of another rigid support ring for an ignition wire in a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention; Figure 4 This is a side view of an ignition wire rigid support ring for a coaxial cylindrical deflagration drive device provided in an embodiment of the present invention; Figure 5 yes Figure 4 A cross-sectional view of one type of AA; Figure 6 yes Figure 4 Another type of AA cross-sectional diagram; Figure 7 This is a cross-sectional view of a rotary handle and a rigid support rod assembled according to an embodiment of the present invention; Figure 8 This is a cross-sectional view of another embodiment of the present invention after the rotary handle and rigid support rod are assembled; Figure 9 This is a structural schematic diagram of the middle section of the deflagration-driven section provided in an embodiment of the present invention; see reference. Figure 2-9As shown, this embodiment provides an ignition wire rigid support ring 1000 for a coaxial cylindrical deflagration drive device, including: a rotating handle 100, a threaded cap 200, and a rigid support rod 300;

[0052] The rotary handle 100 is inserted into the deflagration drive section 1, and the rotary handle 100 is connected to the deflagration drive section 1 through the threaded cap 200;

[0053] The rotary handle 100 includes a first handle portion 101 and a second handle portion 102 connected to the first handle portion 101. The diameter of the first handle portion 101 is smaller than the diameter of the second handle portion 102. The end of the second handle portion 102 away from the first handle portion 101 is connected to a rigid support rod 300. The rigid support rod 300 is located inside the deflagration drive section 1.

[0054] The rigid support rod 300 has a fork 301 at the end away from the second handle portion 102. The fork includes a first fork portion 302, which is located near the second handle portion 102. The first fork portion 302 includes a first fork segment 3021 and a second fork segment 3022 connected to the first fork segment 3021. The root of the first fork portion 302 is on the same horizontal plane as the axis centerline of the detonation drive section 1, and the root of the first fork portion 302 faces the second handle portion 102. The shape of the first fork portion 302 is V-shaped.

[0055] The maximum distance between the first forked section 3021 and the second forked section 3022 is less than the diameter of the mounting hole on the deflagration drive section 1;

[0056] The rigid support rod 300 is made of plastic.

[0057] A sealing element 103 is fitted at the junction between the first handle part 101 and the second handle part 102, and a sealing ring 104 is fitted on the contact surface between the sealing element 103 and the deflagration drive section 1.

[0058] Specifically, the rigid support ring 1000 for the ignition wire of the coaxial cylindrical deflagration drive device includes a rotating handle 100, a threaded cap 200, and a rigid support rod 300.

[0059] The rotary handle 100 is inserted into the deflagration drive section 1, and the rotary handle 100 is connected to the deflagration drive section 1 through the threaded cap 200;

[0060] The rotary handle 100 includes a first handle portion 101 and a second handle portion 102, which are connected together. A rigid support rod 300 is connected to the end of the second handle portion 102 away from the first handle portion 101. Optionally, the second handle portion 102 and the rigid support rod 300 are connected by a thread. To better connect the rigid support rod 300 to the second handle portion 102, the diameter d1 of the first handle portion 101 can be smaller than the diameter d2 of the second handle portion 102. This can be understood as follows: an external thread (not shown in the figure) is provided on the side of the rigid support rod 300 near the second handle portion 102, and an internal thread (not shown in the figure) is provided on the second handle portion 102 to mate with the external thread. The external thread on the rigid support rod 300 and the internal thread on the second handle portion 102 are matched... The rigid support rod 300 is located inside the deflagration drive section 1. To avoid damage to the rotating handle 100, the end of the second handle portion 102 away from the first handle portion 101 can be flush with the inner wall of the deflagration drive section 1. A fork 301 is provided at the end of the rigid support rod 300 away from the second handle portion 102. The fork 301 includes a first fork portion 302, which is located near the second handle portion 102. The first fork portion 302 includes a first fork segment 3021 and a second fork segment 3022. The first fork segment 3021 and the second fork segment 3022 are connected at the end near the second handle portion 102. The root of the first fork portion 302 is on the same horizontal plane as the axis centerline of the deflagration drive section 1, and the root of the first fork portion 302 faces the second handle portion 102.

[0061] In order to facilitate the insertion of the first forked section 302 into the mounting hole 400 of the deflagration drive section 1, the maximum distance d4 between the first forked section 3021 and the second forked section 3022 can be smaller than the diameter d3 of the mounting hole 400 on the deflagration drive section 1.

[0062] To avoid localized breakdown, the rigid support rod 300 is made of a plastic material with good insulation properties;

[0063] To achieve a seal, a sealing element 103 is fitted at the junction between the first handle part 101 and the second handle part 102. A sealing ring 104 is fitted on the contact surface between the sealing element 103 and the deflagration drive section 1, thereby ensuring the airtightness of the deflagration drive section 1 and being able to withstand high air pressure. The sealing element 103 is a sealing pressure ring, and the sealing ring 104 can be an O-ring. Optionally, the first handle part 101, the second handle part 102 and the sealing element are integrally formed into a structure, making the structure more robust and practical.

[0064] In practical use, it should be noted that: an installation hole 400 is provided in the middle of the pipe of the deflagration drive section 1. After inserting the ignition wire into the deflagration drive section 1 and initially straightening it, the rigid support rod 300 is threadedly connected to the rotating handle 100 and then inserted into the deflagration drive section 1 through the installation hole 400. The angle of the rigid support rod 300 is adjusted by rotating the handle 100 so that the ignition wire falls at the root of the fork 301. After installation, the threaded cap 200 is tightened to fix the rotating handle 100 to the deflagration drive section 1.

[0065] As can be seen from the above embodiments, the ignition wire rigid support ring 1000 for the coaxial cylindrical deflagration drive device provided by the present invention achieves at least the following beneficial effects:

[0066] Second, by aligning the root of the first forked portion 302 on the rigid support rod 300 with the center line of the detonation drive section 1 on the same horizontal plane, the first forked portion 302 on the rigid support rod 300 supports the ignition wire, preventing the ignition wire from drooping excessively between the two electrodes and exceeding the allowable range of coaxiality. It should be noted that the detonation drive technology requires two electrodes to be inserted into both ends of the detonation drive section, and an ignition wire is arranged between the two electrodes along the axis of the detonation drive section.

[0067] Second, by rotating the handle 100, the sealing element 103 is rotated, and the sealing ring 104 is fitted on the contact surface between the sealing element 103 and the deflagration drive section 1, which can ensure the airtightness of the deflagration drive section 1 and withstand high air pressure.

[0068] Third, by using a plastic material with good insulation for the rigid support rod 300, the insulation between the rigid support rod 300 and the rotating handle 100 can be guaranteed, thus avoiding localized breakdown.

[0069] In some optional embodiments, the fork 301 further includes a second fork 303 connected to the first fork portion 302. The second fork portion 303 is located on the side away from the second handle portion 102. The second fork portion 303 includes a third fork segment 3031 and a fourth fork segment 3032. The end of the third fork segment 3031 near the second handle portion 102 is connected to the end of the first fork segment 3021 away from the second handle portion 102. The end of the fourth fork segment 3032 near the second handle portion 102 is connected to the end of the second fork segment 3022 away from the second handle portion 102.

[0070] The angle between the first forked segment 3021 and the third forked segment 3031, and the angle between the second forked segment 3022 and the fourth forked segment 3032, are both α1, where 90° > α1 < 180°, and the extension of the third forked segment 3031 does not intersect the extension of the fourth forked segment 3032; or, the angle between the first forked segment 3021 and the third forked segment 3031, and the angle between the second forked segment 3022 and the fourth forked segment 3032, are both α2, where 45° ≥ α2 ≤ 90°, and the extension of the third forked segment 3031 intersects the extension of the fourth forked segment 3032.

[0071] Specifically, the fork 301 also includes a second fork 303 connected to the first fork 302. The second fork 303 is located on the side away from the second handle portion 102. The second fork 303 includes a third fork segment 3031 and a fourth fork segment 3032. The end of the third fork segment 3031 near the second handle portion 102 is connected to the end of the first fork segment 3021 away from the second handle portion 102. The end of the fourth fork segment 3032 near the second handle portion 102 is connected to the end of the second fork segment 3022 away from the second handle portion 102.

[0072] Continue to refer to Figure 2 , Figure 5 and Figure 8 As shown, the angle between the first forked segment 3021 and the third forked segment 3031, and the angle between the second forked segment 3022 and the fourth forked segment 3032, are both α1, where 90° > α1 < 180°, and the extension of the third forked segment 3031 does not intersect the extension of the fourth forked segment 3032. In other words, the space between the first forked portion 302 and the second forked portion 303 is slightly larger. The third forked segment 3031 and the fourth forked segment 3032 are vertically downward parallel line segments. Using this scheme, when the ignition wire falls at the root of the first forked portion 302, it prevents the ignition wire from moving out of the first forked portion 302; this can be understood as preventing the ignition wire from running out of the first forked portion 302. Or,

[0073] Continue to refer to Figure 3 , Figure 6 and Figure 7As shown, the angle between the first forked segment 3021 and the third forked segment 3031, and the angle between the second forked segment 3022 and the fourth forked segment 3032, are both α2, where 45° ≥ α2 ≤ 90°. Furthermore, the extension of the third forked segment 3031 intersects the extension of the fourth forked segment 3032. This means the space between the first forked portion 302 and the second forked portion 303 is slightly smaller, and the angle α2 can be 90°. Using this scheme, when the ignition wire falls at the root of the first forked portion 302, it prevents the ignition wire from moving out of the first forked portion 302. This can be understood as preventing the ignition wire from running out of the first forked portion 302. Regardless of which scheme is used, the second forked portion 303, connected to the first forked portion 302, can prevent the ignition wire from moving out of the first forked portion 302.

[0074] In some alternative embodiments, reference continues to be made to... Figure 5 and Figure 6 As shown, the interface between the first forked section 3021 and the third forked section 3031 is the first interface 304, and the interface between the second forked section 3022 and the fourth forked section 3032 is the second interface 305. The distance d4 between the first interface 304 and the second interface 305 is less than the diameter d3 of the mounting hole 400 on the deflagration drive section 1.

[0075] Specifically, the interface between the first forked section 3021 and the third forked section 3031 is the first interface 304, and the interface between the second forked section 3022 and the fourth forked section 3032 is the second interface 305. The distance d4 between the first interface 304 and the second interface 305 is less than the diameter d3 of the mounting hole 400 on the deflagration drive section 1. In other words, the maximum distance d4 between the first forked section 3021 and the second forked section 3022 in the first forked section is less than the diameter d3 of the mounting hole 400 on the deflagration drive section 1. With this solution, there is no need to disassemble the heavy deflagration drive section 1. The ignition wire rigid support ring 1000 can be disassembled and installed outside the tube wall of the deflagration drive section 1 through the mounting hole 400, which greatly improves work efficiency.

[0076] In some alternative embodiments, reference continues to be made to... Figure 5 , Figure 6 , Figure 7 and Figure 8 As shown, along the first direction X, the length of the handle is 20cm-40cm. The first direction X is from the first handle part 101 to the second handle part 102. This design makes it convenient for the user to operate the rotating handle 100. Of course, the length of the rigid support rod 300 along the first direction can be the radius of the pipe diameter of the deflagration drive section 1, and can be adjusted according to the size of the pipe diameter of the deflagration drive section 1, such as the rigid support rod 300 being 2cm-100cm.

[0077] Figure 9This is a schematic diagram of the structure of the middle section of the deflagration drive section provided in an embodiment of the present invention; Figure 10 This is a schematic diagram of the structure of a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel provided in an embodiment of the present invention; Figure 11 yes Figure 10 Enlarged view of the structure at point B in the middle; Figure 12 yes Figure 10 Enlarged view of the structure of the intermediate discharge system; Figure 13 This is a logic block diagram of a discharge system provided in an embodiment of the present invention. Figures 9-13 As shown, this embodiment provides a coaxial cylindrical deflagration drive device for shock tubes / wind tunnels, including a deflagration drive section 1, a driven section 2, a diaphragm 5 for separating the deflagration drive section 1 and the driven section 2, a blind plate 14, an ignition wire rigid support ring 1000, and a discharge system 7, wherein one end of the deflagration drive section 1 is connected to the driven section 2, and the other end is connected to the blind plate 14.

[0078] The deflagration driving section 1 is a straight pipe with a constant cross section. A first electrode 11 and a second electrode 12 extending radially Y are inserted into the deflagration driving section 1. The first electrode 11 is located on the side of the deflagration driving section close to the blind plate 14, and the second electrode 12 is located on the side of the deflagration driving section 1 close to the driven section 2. An ignition wire 13 extending axially X is electrically connected between the first electrode 11 and the second electrode 12. The axial direction X is the direction from the center line of the axis of the deflagration driving section 1 to the driven section 2, and the radial direction Y intersects with the axial direction X.

[0079] Along the axial direction X, the length between the first electrode 11 and the blind plate 14 is L1, and the length between the second electrode 12 and the diaphragm 5 is L2. The lengths of L1 and L2 are limited to 0.5cm-20cm.

[0080] The deflagration drive section 1 has an opening 8 that mates with the first electrode 11 and the second electrode 12. A sealing ring 81 is provided on the contact surface between the first electrode 11, the second electrode 12 and the opening 8.

[0081] The deflagration drive section 1 is also provided with a mounting hole 400 for mounting an ignition wire rigid support ring 1000. The mounting hole 400 is located in the middle of the deflagration drive section 1. The ignition wire rigid support ring 1000 is inserted into the mounting hole 400. The ignition wire rigid support ring 1000 is the aforementioned ignition wire rigid support ring 1000 used for the coaxial cylindrical deflagration drive device.

[0082] The deflagration drive section 1 is filled with a combustible mixture;

[0083] The discharge system 7 includes a high-voltage capacitor 71, an ignition switch 720, and an unloading switch 730. The ignition circuit 72 is formed by the positive terminal of the high-voltage capacitor 71, the ignition switch 720, the first electrode 11, the ignition wire 13, the second electrode 12, and the negative terminal of the high-voltage capacitor 71. The unloading circuit 73 is formed by the positive terminal of the high-voltage capacitor 71, the unloading switch 730, and the negative terminal of the high-voltage capacitor 71. The ignition circuit 72 and the unloading circuit 73 are connected in parallel. The high-voltage capacitor 71 is used to store high-voltage electricity and discharge it to the ignition wire.

[0084] Specifically, the coaxial cylindrical deflagration drive device for shock tubes / wind tunnels includes a deflagration drive section 1 and a driven section 2. One end of the deflagration drive section 1 is connected to the driven section 2, and the other end is connected to a blind flange 14. A diaphragm 5 is installed between the deflagration drive section 1 and the driven section 2. The driven section 2 is connected to the test section 4 through a nozzle 3. The blind flange 14 is a flange cover. By using the blind flange 14 to block the end of the deflagration drive section 1, there is no need to use the traditional detonation unloading section and install a diaphragm between the detonation unloading section and the deflagration drive section. This not only helps to reduce the space occupied, but also reduces the cost.

[0085] A first electrode 11 and a second electrode 12 extending radially Y are inserted into the deflagration driving section 1. The first electrode 11 is located on the side of the deflagration driving section 1 near the blind plate 14, and the second electrode 12 is located on the side of the deflagration driving section 1 near the driven section 2. That is, the first electrode 11 and the second electrode 12 are inserted at both ends of the deflagration driving section 1. An ignition wire 13 extending axially is electrically connected between the first electrode 11 and the second electrode 12. The axial direction X is the direction from the blind plate 14 to the center line of the driven section 2. The radial direction Y intersects with the axial direction X. Optionally, the ignition wire 13 can be any metal material selected from copper, silver, nickel-chromium, tungsten and alloys. The length of the ignition wire 13 can be adjusted according to the length of the deflagration driving section 1.

[0086] The axial distance from the first electrode 11 to the blind plate 14 is L1, and the axial distance from the second electrode 12 to the diaphragm 5 is L2. If the lengths of L1 and L2 are less than 0.5cm, breakdown may occur, leading to equipment damage or endangering personnel safety. If the lengths of L1 and L2 are greater than 20cm, the combustion of the combustible mixture in the deflagration drive section 1 may be unstable. Therefore, limiting the lengths of L1 and L2 to 0.5cm-20cm not only allows the ignition wire 13 to be arranged as long as possible along the axial direction in the deflagration drive section, which can further enable the combustion of the combustible mixture in the deflagration drive section 1 to be more complete, but also avoids the distance between the first electrode 11 and the end of the deflagration drive section and between the second electrode 12 and the diaphragm 5 being too close, thereby avoiding breakdown and ensuring the safety of equipment and personnel.

[0087] Figure 11 yes Figure 10 Enlarged view of the structure at point B; where, Figure 10The enlarged view at point C is the same as the enlarged view at point B. An opening 8 is provided on the deflagration driving section 1 to cooperate with the first electrode 11 and the second electrode 12. Figure 11 In order to show the opening 8 in the figure, the diameter of the opening 8 is drawn to be larger than the actual size. The opening 8 is matched with the first electrode 11 and the second electrode 12 is matched with the opening 8. The opening 8 facilitates the insertion of the first electrode 11 and the second electrode 12 into the combustion driving section 1. In order to ensure the sealing of the deflagration driving section 1, after the first electrode 11 is inserted into the deflagration driving section 1, a sealing ring 81 is set on the contact surface of the deflagration driving section 1 where the first electrode 1 contacts the opening 8, and a sealing ring 81 is set on the contact surface of the deflagration driving section 1 where the second electrode 12 contacts the opening 8.

[0088] A mounting hole 400 for mounting an ignition wire rigid support ring 1000 is also provided on the deflagration drive section 1. The mounting hole 400 is located in the middle of the deflagration drive section 1. The ignition wire rigid support ring 1000 is the aforementioned ignition wire rigid support ring 1000 for a coaxial cylindrical deflagration drive device, including a rotating handle 100 and a rigid support rod 300. The rigid support rod 300 is threadedly connected to the rotating handle 100, and the rotating handle 100 is connected to the deflagration drive section 1 via a threaded cap 200. The mechanical connection is used to support the ignition wire 13 via the first forked portion 302 on the rigid support rod 300. The first forked portion 302 is V-shaped, and the root of the first forked portion 302 is on the same horizontal plane as the axis center line of the combustion drive section 1. The root of the first forked portion 3021 faces the second handle portion 102 and can provide support for the middle part of the ignition wire 13, thereby preventing the ignition wire 13 from drooping excessively between the first electrode 11 and the second electrode 12, exceeding the allowable range of coaxiality.

[0089] The deflagration drive section 1 is filled with a combustible mixture, which may include fuel, oxidant, and inert gas. The fuel is hydrogen, carbon monoxide, or alkanes, alkenes, and alkynes, or other combustible gases. The oxidant is oxygen or nitrous oxide, or other oxidizing gases. The inert gas is nitrogen, rare gases, or carbon dioxide, or other gases that do not participate in the combustion reaction. The ratio of fuel:oxidant:inert gas can be 1:1:1, 2:1:1, or 2:1:7. Of course, the ratio of fuel, oxidant, and inert gas is set according to the specific equipment and experimental requirements.

[0090] It also includes a discharge system 7, which includes a high-voltage capacitor 71, an ignition switch 720, and an unloading switch 730. The positive terminal of the high-voltage capacitor 71, the ignition switch 720, the first electrode 11, the ignition wire 13, the second electrode 12, and the negative terminal of the high-voltage capacitor 71 constitute an ignition circuit 72. The positive terminal of the high-voltage capacitor 71, the unloading switch 730, and the negative terminal of the high-voltage capacitor 71 constitute an unloading circuit 73. The ignition circuit 72 and the unloading circuit 73 are connected in parallel. The high-voltage capacitor 71 is used to store high-voltage electricity.

[0091] After the high-voltage capacitor 71 is charged, the ignition switch 720 is closed first. The high-voltage capacitor 71 is connected to the ignition wire 13 through the first electrode 11 and the second electrode 12 respectively, and ignition begins. After a predetermined time, the unloading switch 730 is closed to short-circuit the positive and negative terminals of the high-voltage capacitor 71. The charge in the high-voltage capacitor 71 is then instantly returned to the high-voltage capacitor 71 through the unloading circuit 73, completing the unloading. The predetermined time can be 5-30 milliseconds.

[0092] The assembly sequence of the coaxial cylindrical deflagration drive device for shock tubes / wind tunnels is as follows:

[0093] Provides deflagration drive section 1;

[0094] First, an opening 8 is provided on the deflagration driving section 1 for placing the first electrode 11 and the second electrode 12; second, a sealing ring 81 is installed on the contact surface between the first electrode 11 and the second electrode 12 and the opening 8, and then the first electrode 11 and the second electrode 12 are inserted into the opening 8, with the first electrode 11 located on the side of the deflagration driving section near the blind plate 14, and the second electrode 12 located on the side of the deflagration driving section 1 near the driven section 2; an ignition coil extending along the axial direction X is connected between the first electrode 11 and the second electrode 12. After initially straightening the ignition wire 13, the rigid support rod 300 is threadedly connected to the rotating handle 100 and inserted into the deflagration drive section 1 through the mounting hole 400. The angle of the rigid support rod 300 is adjusted by rotating the handle 100 so that the ignition wire 13 falls at the root of the first fork 302. After installation, the threaded cap 200 is tightened to achieve mechanical connection between the rotating handle 100 and the deflagration drive section 1. The second fork 303 is used to prevent the ignition wire 13 from moving out of the first fork 302.

[0095] A diaphragm 5 is installed between the deflagration driving section 1 and the driven section 2. The driven section 2 is connected to one end of the deflagration driving section 1 near the diaphragm 5, and a blind plate 14 is connected to the other end.

[0096] The deflagration drive section 1 is filled with a combustible mixture;

[0097] Connect the discharge system 7, and form an ignition circuit 72 by connecting the positive terminal of the high voltage capacitor 71, the ignition switch 720, the first electrode 11, the ignition wire 13, the second electrode 12, and the negative terminal of the high voltage capacitor 71; form an unloading circuit 73 by connecting the positive terminal of the high voltage capacitor 71, the unloading switch 730, and the negative terminal of the high voltage capacitor 71; the ignition circuit 72 and the unloading circuit 73 are connected in parallel.

[0098] Assemble the coaxial cylindrical deflagration drive device for shock tubes / wind tunnels according to the above assembly sequence. This not only allows for better insertion of the first and second electrodes and more precise placement of the ignition wire 13, but also prevents leakage of combustible mixture, ensuring personal safety, and facilitating operation.

[0099] Of course, without considering the discharge of the high-voltage capacitor to the ignition wire, the above assembly sequence can be appropriately adjusted. After installing the driven section 2 or the blind plate 14, the discharge system can be connected first, and then the combustible mixture can be charged into the deflagration drive section 1, as follows:

[0100] First, it provides the deflagration drive section 1;

[0101] Second, firstly, an opening 8 is provided on the deflagration driving section 1 for placing the first electrode 11 and the second electrode 12; secondly, a sealing ring 81 is installed on the contact surface between the first electrode 11 and the second electrode 12 and the opening 8, and then the first electrode 11 and the second electrode 12 are inserted into the opening 8, with the first electrode 11 located on the side of the deflagration driving section near the blind plate 14, and the second electrode 12 located on the side of the deflagration driving section 1 near the driven section 2; a point extending along the axial direction X is connected between the first electrode 11 and the second electrode 12. Ignition wire 13; After initially straightening the ignition wire 13, connect the rigid support rod 300 to the rotating handle 100 by thread, insert it into the deflagration drive section 1 through the mounting hole 400, and adjust the angle of the rigid support rod 300 by rotating the handle 100 so that the ignition wire 13 falls at the root of the first fork 302. After installation, tighten the threaded cap 200 to realize the mechanical connection between the rotating handle 100 and the deflagration drive section 1, and use the second fork 303 to prevent the ignition wire 13 from moving out of the first fork 302.

[0102] Third, a diaphragm is installed between the deflagration driving section 1 and the driven section 2. The driven section 2 is connected to one end of the deflagration driving section 1 near the diaphragm 5, and a blind plate 14 is connected to the other end.

[0103] Fourth, connect the discharge system 7, and form an ignition circuit 72 by connecting the positive terminal of the high-voltage capacitor 71, the ignition switch 720, the first electrode 11, the ignition wire 13, the second electrode 12, and the negative terminal of the high-voltage capacitor 71; form an unloading circuit 73 by connecting the positive terminal of the high-voltage capacitor 71, the unloading switch 730, and the negative terminal of the high-voltage capacitor 71; the ignition circuit 72 and the unloading circuit 73 are connected in parallel.

[0104] Fifth, the combustion-driven section 1 is filled with a combustible mixture.

[0105] It should be noted that: First, a deflagration driving section 1 is provided; second, firstly, an opening 8 is formed on the deflagration driving section 1 for placing a first electrode 11 and a second electrode 12; secondly, a sealing ring 81 is installed on the contact surface between the first electrode 11 and the second electrode 12 and the opening 8, and then the first electrode 11 and the second electrode 12 are inserted into the opening 8, with the first electrode 11 located on the side of the deflagration driving section near the blind plate 14, and the second electrode 12 located on the side of the deflagration driving section 1 near the driven section 2; an ignition wire 13 extending along the axial direction X is connected between the first electrode 11 and the second electrode 12; thirdly, a diaphragm is installed between the deflagration driving section 1 and the driven section 2, with the driven section 2 connected to one end of the deflagration driving section 1 near the diaphragm 5, and the blind plate 14 connected to the other end; the assembly sequence of the above three steps is irreversible, that is, the assembly sequence cannot be reversed, otherwise it cannot be implemented.

[0106] The working principle is as follows: Within the deflagration drive section 1, there is an ignition wire 13 arranged axially (X). After the high-voltage capacitor 71 is charged, the ignition switch 720 is closed. The high-voltage capacitor 71 is connected to the ignition wire 13 through the first electrode 11 and the second electrode 12. A high voltage of several thousand to tens of thousands of volts is applied across the ignition wire 13. At the instant the ignition switch 720 is energized, the ignition wire 13 heats up intensely, igniting the combustible mixture near the ignition wire 13 within microseconds. After ignition, a columnar flame is formed and expands radially. The ignition wire 13 is made strictly coaxial with the pipe of the deflagration drive section 1 to ensure that all parts along the axial direction burn out simultaneously. Since the discharge process of the high-voltage capacitor 71 is longer than the combustion process, the remaining charge in the high-voltage capacitor 71 needs to be discharged before the combustion ends. Therefore, after a predetermined time, the unloading switch 730 is closed to short-circuit the positive and negative terminals of the high-voltage capacitor 71. The charge in the high-voltage capacitor 71 then returns to the high-voltage capacitor 71 instantly through the unloading circuit to complete the unloading, thereby preventing the combustion products near the positive terminal of the high-voltage capacitor 71 from breaking down and causing a safety accident.

[0107] It should be noted that: detonation drive requires the formation of a detonation wave propagating axially within the drive section pipe, while deflagration drive involves igniting the gas in the deflagration drive section 1 pipe simultaneously along the axial direction, completing combustion in a deflagration rather than detonation manner, and ending combustion simultaneously along the axial direction X.

[0108] The effective operating time of a shock tube / wind tunnel is typically in the range of a few milliseconds to 100 milliseconds. In order to provide accurate test conditions, it is essential to ensure that the combustible mixture in the deflagration drive section is ignited and burned out simultaneously.

[0109] As can be seen from the above embodiments, the coaxial cylindrical deflagration drive device for shock tubes / wind tunnels provided by the present invention achieves at least the following beneficial effects:

[0110] First, in the prior art, detonation drives the formation of axially propagating detonation waves in the driving section pipe. Since the extremely high pressure peak of the detonation wave cannot be fully used for driving, the effective pressure provided by detonation driving is much lower than the pressure limit of the equipment. However, in this invention, deflagration replaces detonation, and there is no pressure peak in detonation. The combustion pressure can be 100% used to compress the test gas, thus increasing the pressure of the test gas.

[0111] Second, the limit of the mixture ratio in deflagration is much wider than that in detonation, and the temperature and sound velocity range of the driving gas are larger, so the corresponding total temperature range of the test gas is also larger than that driven by detonation.

[0112] Third, by aligning the root of the first fork on the rigid support rod with the center line of the combustion drive section on the same horizontal plane, the ignition wire can be supported by the first fork on the rigid support rod, preventing the ignition wire from drooping excessively between the two electrodes and exceeding the allowable range of coaxiality; the second fork connected to the first fork prevents it from moving out of the first fork.

[0113] Figure 14 This is a schematic diagram of a shock tube / wind tunnel provided in an embodiment of the present invention; another embodiment of the present invention provides a shock tube / wind tunnel, including a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel provided in an embodiment of the present invention.

[0114] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A rigid support ring for an ignition wire in a coaxial cylindrical deflagration drive device, characterized in that, include: Rotary handle, threaded nut, and rigid support rod; The rotary handle is inserted into the deflagration drive section, and the rotary handle is connected to the deflagration drive section through the threaded cap; The rotary handle includes a first handle portion and a second handle portion connected to the first handle portion. The diameter of the first handle portion is smaller than the diameter of the second handle portion. The end of the second handle portion away from the first handle portion is connected to the rigid support rod. The rigid support rod is located within the deflagration drive section. The rigid support rod is provided with a fork at the end away from the second handle. The fork includes a first fork portion, which is located on the side close to the second handle. The first fork portion includes a first fork segment and a second fork segment connected to the first fork segment. The root of the first fork portion is on the same horizontal plane as the axis centerline of the combustion drive section, and the root of the first fork portion faces the side of the second handle. The first forked portion is V-shaped; The maximum distance between the first forked section and the second forked section is less than the diameter of the mounting hole on the deflagration drive section; A sealing element is fitted at the junction between the first handle part and the second handle part, and a sealing ring is fitted on the contact surface between the sealing element and the deflagration drive section. The rigid support rod is made of plastic.

2. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to claim 1, characterized in that, The fork also includes a second fork connected to the first fork. The second fork is located on the side away from the second handle. The second fork includes a third fork segment and a fourth fork segment. The end of the third fork segment near the second handle is connected to the end of the first fork segment away from the second handle. The end of the fourth fork segment near the second handle is connected to the end of the second fork segment away from the second handle. The angle between the first forked segment and the third forked segment, and the angle between the second forked segment and the fourth forked segment are both α1, where 90° > α1 < 180°, and the extension of the third forked segment does not intersect the extension of the fourth forked segment; or, the angle between the first forked segment and the third forked segment, and the angle between the second forked segment and the fourth forked segment are both α2, where 45° ≥ α2 ≤ 90°, and the extension of the third forked segment intersects the extension of the fourth forked segment.

3. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to claim 2, characterized in that, The interface between the first forked segment and the third forked segment is the first interface, and the interface between the second forked segment and the fourth forked segment is the second interface. The distance between the first interface and the second interface is less than the diameter of the mounting hole on the deflagration drive segment.

4. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to claim 1, characterized in that, The second handle is connected to the rigid support rod by a thread.

5. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to claim 1, characterized in that, The first handle portion, the second handle portion, and the sealing element are integrally formed.

6. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to claim 1, characterized in that, The sealing element is a sealing pressure ring.

7. The rigid support ring for the ignition wire of the coaxial cylindrical deflagration drive device according to any one of claims 1-6, characterized in that, Along the first direction, the length of the handle is 20cm-40cm, and the first direction is the direction from the first handle portion to the second handle portion.

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