Double-side gas-filled premixed film clamping device for coaxial cylindrical deflagration drive device

Abstract

The present invention discloses a double-side inflated premixed membrane device for a coaxial cylindrical deflagration drive device, comprising a first membrane ring, a second membrane ring and a third membrane ring; a membrane is arranged between the second membrane ring and the third membrane ring; at least two first air inlet channels are arranged on the second membrane ring; a first concave portion is arranged on the first membrane ring; a metal wire is arranged in the mixing channel, and the metal wire is spiral; each first air inlet channel is connected with the mixing channel; the mixing channel is connected with the deflagration drive section through the outlet channel, and the outlet channel has a mixed air outlet, and the mixed air outlet is located on the inner wall of the second membrane ring; the mixing channel has an air inlet section, a mixing section and an air outlet section; a second air inlet channel is arranged on the third membrane ring, and the second air inlet channel is connected with the driven section. The present invention can make the airflow generate turbulence when flowing through, thereby strengthening the mixing of the components, and then the mixed air flows into the deflagration drive section through the outlet channel, and the uniformity of the mixed air is significantly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of experimental research on high-temperature and high-speed gas dynamics, high-speed aircraft, etc., and more specifically, to a double-side inflated premixed film device for a coaxial cylindrical deflagration drive device. Background Art

[0002] Shock tube / wind tunnel is a kind of experimental equipment widely used in the fields of high-temperature and high-speed gas dynamics, high-speed aircraft, etc. The basic principle is: high-pressure driving gas compresses low-pressure test gas through shock waves to achieve the required test state. Figure 1 As shown, a typical shock tube / wind tunnel includes a driving section 1', a driven section 2', a nozzle 3' and a test section 4'; before the test, the driving section 1' and the driven section 2' are separated by a diaphragm 5', the driving section 1' is filled with high-pressure driving gas, and the driven section 2' is filled with low-pressure test gas; during the test, the diaphragm 5' ruptures, the high-pressure gas expands and enters the driven section 2', and a fast-moving shock wave is generated in the driven section 2'; if the gas after the shock wave is directly used to carry out the test, the equipment operates in the shock tube mode; if the test is carried out using the test gas accelerated by the nozzle 3', the equipment operates in the shock wind tunnel mode.

[0003] The total temperature and total pressure range of the test gas are the main indicators for measuring the equipment's capabilities, and both depend on the driving capacity of the high-pressure driving gas. Normal temperature and high-pressure gas can no longer meet the increasingly demanding test requirements. For this reason, three high-performance driving technologies have been developed at home and abroad: piston drive, heated light gas drive, and detonation drive. Among them, the detonation drive technology has the characteristics of low cost, simple structure and relatively safe, 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 of the 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 of the Chinese Academy of Sciences developed the JF-10 detonation-driven high-enthalpy shock tunnel [see Yu Hongru, Zhao Wei, and Yuan Shengxue's Performance of Hydrogen-Oxygen Detonation-Driven Shock Tunnels - Aerodynamic Test 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 the Aachen University of Technology in Germany in 1993. In 1994, NASA modified the original free piston driven design and built a forward detonation driven high enthalpy shock tunnel (HYPULSE) at GASL. The tunnel can operate in both reflected shock tunnel mode and expansion tube mode [see Chue RSM, Tsai CY, Bakos RJ, Erdos JI, Rogers RC (2002) NASA's HYPULSE Facility at GASL-ADual 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 drive requires the formation of a detonation wave that propagates axially within the drive section. The uneven flow field behind the detonation wave causes the following problems in this drive technology: first, the range of gas mixture ratios that can detonate is much narrower than the range that can deflagrate, and the temperature and sound velocity ranges of the driving gas are also correspondingly narrower, thus limiting the total temperature range of the test gas that can be provided by the detonation drive; second, the effective driving pressure provided by the detonation drive does not exceed 40% of the pressure limit of the equipment, limiting the total pressure range of the test gas.

[0006] In order to overcome the above-mentioned problems of detonation drive, a coaxial cylindrical deflagration drive technology was proposed. This technology requires high-voltage electrodes to be plugged in at both ends of the drive section, and an ignition wire coaxial with the drive section is arranged between the two high-voltage electrodes. The ignition wire is used to ignite the gas on the axis at the same time. This method has strict requirements on the mixing uniformity of the driving gas, and the traditional inflation method cannot meet the requirements. In order to simplify the structure and improve safety, the traditional inflation structure usually directly sets independent inflation holes on the pipe wall, and each driving gas enters the driving section pipeline separately and then mixes; the traditional inflation structure also has no special requirements for the design of the air inlet position, and it can be located at any position in the driving section. Experiments show that the traditional inflation structure cannot meet the gas mixing uniformity required by the coaxial cylindrical deflagration drive technology. Existing document 1 (CN111579200A) discloses a screw temperature-controlled film clamping device, which includes a left flange and a right flange arranged in front and back, the centers of the left flange and the right flange are each provided with an internal threaded hole, the circumference of the left flange is provided with evenly distributed internal threaded holes, and the circumferential position of the right flange is provided with through holes corresponding to the internal threaded holes; the driving section is a cylinder I, the right end of the cylinder is provided with an external thread, the external thread of the driving section is assembled with the internal threaded hole I of the left flange through threads, the driving section is fixed on the left end face of the left flange, and the cavity of the driving section is filled with high-pressure driving gas; the driven section is a cylinder II, the left end of the cylinder II is provided with an external thread, the external thread of the driven section is assembled with the internal threaded hole I of the right flange through threads, the driven section is fixed on the right end face of the right flange, and the cavity of the driven section is filled with low-pressure driven gas; On the central axis between the right end face of the flange and the left end face of the right flange, horizontally movable diaphragm I, diaphragm ring I, diaphragm II and diaphragm ring II are fixed in sequence from front to back; telescopic cylinders are also symmetrically installed between the right end face of the left flange and the left end face of the right flange; the connecting screw passes through the internal threaded hole II and the through hole from left to right in sequence, the left end of the connecting screw is assembled with the internal threaded hole II through the external thread, and the left end of the connecting screw is fixed to the left flange, and the right end of the connecting screw is assembled with the fastening nut through the external thread, and the right end of the connecting screw is fixed to the right flange; a cavity is opened on the central axis of the connecting screw, and a heater is installed in the cavity between the right end face of the left flange and the left end face of the right flange, and a water cooling jacket is mounted on the outer sleeve of the connecting screw at the corresponding position of the heater, and the heater is connected to an external power supply, but the above technical problems are still not solved by the above scheme.

[0007] Existing document 2 (CN102407947A) discloses a shock tunnel detonation dual-drive device, comprising: a shock tunnel, the shock tunnel having a detonation drive section, one end of the detonation drive section is provided with a detonation discharge section, and the other end is provided with a driven section; a first diaphragm is provided between the detonation discharge 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 at a section of the detonation drive section close to the detonation discharge section, and a reverse detonation drive ignition device is provided at a section of the detonation drive section close to the driven section; a controllable delay trigger is connected between the forward detonation drive ignition device and the reverse detonation drive ignition device. The invention discloses a device and a method as follows: 1) a forward detonation ignition device is arranged at one end of the detonation driving section of the shock tunnel close to the detonation unloading section, and a reverse detonation driving ignition device is arranged at one end of the detonation driving section close to the driven section; 2) ignition is performed by the forward detonation ignition device to form a forward driven detonation wave; 3) after the forward detonation wave propagates along the detonation driving section for a predetermined time, ignition is performed by the reverse detonation driving ignition device to form a reverse driven detonation wave; 4) the reverse driven detonation wave tears a diaphragm arranged between the driven section and the detonation driving section, and a moving shock wave is formed after the forward detonation wave intersects with the reverse detonation wave, and the moving shock wave enters the driven section to compress the test gas in the driven section.

[0008] In order to meet the requirements of coaxial cylindrical deflagration driving technology for the mixing uniformity of the driving gas, the present invention proposes a double-sided air-filled premixed membrane device for a coaxial cylindrical deflagration driving device, and the double-sided air-filled premixed membrane device for a coaxial cylindrical deflagration driving device is not easily conceived by technical personnel in this field. Summary of the invention

[0009] In view of this, the present invention provides a double-side inflated premixed membrane device for a coaxial cylindrical deflagration drive device, comprising a first membrane ring, a second membrane ring and a third membrane ring, wherein the first membrane ring is connected to the deflagration drive section, the third membrane ring is connected to the driven section, and the second membrane ring is located between the first membrane ring and the third membrane ring;

[0010] A diaphragm is provided between the second clamping membrane ring and the third clamping membrane ring;

[0011] At least two first air inlet channels are arranged on the second clamping membrane ring along the circumferential direction;

[0012] A first concave portion is provided on one side of the first clamping membrane ring close to the second clamping membrane ring;

[0013] A first convex portion matching with the first concave portion is disposed on one side of the second clamping membrane ring close to the first clamping membrane ring, the first concave portion is connected to the first convex portion, and a mixing channel along the circumferential direction is disposed on the first convex portion;

[0014] A metal wire is arranged in the mixing channel, and the metal wire is in a spiral shape;

[0015] Each of the first air intake channels is in communication with the mixing channel;

[0016] The mixing channel is connected to the inside of the deflagration driving section through an outlet channel, and the outlet channel has an air mixing outlet, and the air mixing outlet is located on the inner wall of the second clamping membrane ring;

[0017] The mixing channel comprises an air inlet, a mixing portion and an air outlet, wherein the air inlet is located at one end of the mixing channel, the air outlet is located at the other end of the mixing channel, and the mixing portion is located between the air inlet and the air outlet;

[0018] The end of the air inlet close to the mixing portion is connected to the end of the air outlet close to the mixing portion through the mixing portion, and a blocking portion is provided between the end of the air inlet away from the mixing portion and the end of the air outlet away from the mixing portion;

[0019] The third clamping membrane ring is provided with a second air inlet channel, and the second air inlet channel is communicated with the driven section.

[0020] Optionally, the mixed gas outlet is close to one side of the diaphragm.

[0021] Optionally, the air outlet channel includes a first air inlet section and a first air outlet section connected to the first air inlet section, the first air inlet section is located on a side of the air outlet channel close to the mixing channel, the first air outlet section is located on a side of the air outlet channel away from the mixing channel, the first air inlet section is connected to the mixed air outlet through the first air outlet section, and the angle between the first air inlet section and the first air outlet section is 80°-100°.

[0022] Optionally, the first air inlet channel includes a second air inlet section and a second air outlet section connected to the second air inlet section, the second air inlet section is located close to the side of the first air inlet channel away from the mixing channel; the second air outlet section is located close to the side of the mixing channel away from the first air inlet channel, and the angle between the second air inlet section and the second air outlet section is 80°-100°.

[0023] Optionally, the metal wire is located in the mixing section.

[0024] Compared with the prior art, the double-sided air-filled premixed film clamping device for a coaxial cylindrical deflagration drive device provided by the present invention achieves at least the following beneficial effects:

[0025] First, in the prior art, independent inflation holes are simply set on the tube wall, and each driving gas enters the deflagration driving section pipeline separately and then mixes, resulting in poor mixing effect. In the present invention, each driving gas first flows into the mixing channel of the second clamp before entering the deflagration driving section. Since a spiral metal wire is fixed in the mixing channel, turbulence can be generated when the airflow passes through, thereby strengthening the mixing of the components. After that, the mixed gas flows into the deflagration driving section through the gas outlet channel, and the uniformity of the mixed gas is significantly improved;

[0026] Second, compared with the prior art, there is no special requirement for the position of the air inlet in the inflation structure, and the mixed gas outlet in the present invention is located very close to the diaphragm, which can significantly reduce the dead angle of gas flow and ensure the consistency of gas component distribution in the pipelines of the driving section 1 and the driven section 2.

[0027] Of course, any product implementing the present invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0028] Further features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

[0030] Figure 1 It is a schematic diagram of the structure of a shock tube / wind tunnel provided in the prior art;

[0031] Figure 2 It is a structural schematic diagram of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention;

[0032] Figure 3 It is an exploded diagram of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention;

[0033] Figure 4 is a side view of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention;

[0034] Figure 5 yes Figure 4 Sectional view of AA in the middle;

[0035] Figure 6 is a front view of a second clamping membrane ring provided by an embodiment of the present invention;

[0036] Figure 7 is a transparent view of a second clamping membrane ring provided by an embodiment of the present invention;

[0037] Figure 8 is a schematic diagram of the structure of a metal wire provided by an embodiment of the present invention;

[0038] Fig. 9 is a bottom view of a second clamping membrane ring provided by an embodiment of the present invention;

[0039] Fig.10 is a bottom view of a first clamping membrane ring provided by an embodiment of the present invention;

[0040] Fig.11 It is a schematic structural diagram of a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel provided by an embodiment of the present invention;

[0041] Fig.12 yes Fig.11 A magnified view of the structure at B in the middle;

[0042] Fig.13 yes Fig.11 A magnified diagram of the structure of the discharge system;

[0043] Fig.14 is a logic block diagram of a discharge system provided by an embodiment of the present invention;

[0044] Fig.15 It is a schematic diagram of the structure of a shock tube / wind tunnel provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless otherwise specifically stated.

[0046] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

[0047] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0048] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0049] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0050] Figure 2It is a structural schematic diagram of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention; Figure 3 It is an exploded diagram of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention; Figure 4 is a side view of a double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device provided by an embodiment of the present invention;

[0051] Figure 5 yes Figure 4 Sectional view of AA in the middle; Figure 6 is a front view of a second clamping membrane ring provided by an embodiment of the present invention; Figure 7 is a transparent view of a second clamping membrane ring provided by an embodiment of the present invention; Figure 8 is a schematic diagram of the structure of a metal wire provided by an embodiment of the present invention; Fig. 9 is a bottom view of a second clamping membrane ring provided by an embodiment of the present invention; Fig.10 is a bottom view of the first clamping membrane ring provided by an embodiment of the present invention; Figure 2-Figure 10 As shown, this embodiment provides a double-side inflated premixed film clamping device 1000 for a coaxial cylindrical deflagration drive device, comprising a first film clamping ring 100, a second film clamping ring 200 and a third film clamping ring 300, wherein the first film clamping ring 100 is connected to the deflagration drive section 1, the third film clamping ring 300 is connected to the driven section 2, and the second film clamping ring 200 is located between the first film clamping ring 100 and the third film clamping ring 300;

[0052] A diaphragm 5 is provided between the second clamping membrane ring 200 and the third clamping membrane ring 300;

[0053] At least two first air inlet channels 201 are arranged on the second clamping membrane ring 200 along the circumferential direction;

[0054] A first concave portion 101 is provided on one side of the first clamping membrane ring 100 close to the second clamping membrane ring 200;

[0055] A first convex portion 202 matching with the first concave portion 101 is disposed on the second membrane ring 200 near the first membrane ring 100. The first concave portion 101 is connected to the first convex portion 202. A mixing channel 203 is disposed on the first convex portion 202 along the circumferential direction.

[0056] A metal wire 204 is disposed in the mixing channel 203, and the metal wire 204 is spiral-shaped;

[0057] Each first air intake channel 201 is connected to the mixing channel 203;

[0058] The mixing channel 203 is connected to the inside of the deflagration driving section 1 through the gas outlet channel 205. The gas outlet channel 205 has a mixed gas outlet 206. The mixed gas outlet 206 is located on the inner wall of the second clamping membrane ring 200.

[0059] The mixing channel 203 has an air inlet 207, a mixing portion 208 and an air outlet 209. The air inlet 207 is located at one end of the mixing channel 203, the air outlet 209 is located at the other end of the mixing channel 203, and the mixing portion 208 is located between the air inlet 207 and the air outlet 209.

[0060] An end of the air inlet 207 close to the mixing portion 208 is connected to an end of the air outlet 209 close to the mixing portion 208 through the mixing portion 208, and a blocking portion 210 is provided between an end of the air inlet 207 away from the mixing portion 208 and an end of the air outlet 209 away from the mixing portion 208;

[0061] The third clamping membrane ring 300 is provided with a second air inlet channel 301 , and the second air inlet channel 301 is communicated with the driven section 2 .

[0062] Specifically, the double-side inflated premixed membrane device 1000 for the coaxial cylindrical deflagration drive device comprises a first membrane ring 100, a second membrane ring 200 and a third membrane ring 300, the first membrane ring 100, the second membrane ring 200 and the third membrane ring 300 are respectively annular in shape, wherein the first membrane ring 100 is connected to the deflagration driving section 1, the third membrane ring 300 is connected to the driven section 2, and the second membrane ring 200 is located between the first membrane ring 100 and the third membrane ring 300;

[0063] A diaphragm 5 is installed between the second diaphragm ring 200 and the third diaphragm ring 300, and the diaphragm 5 separates the deflagration driving section 1 and the driven section 2;

[0064] At least two first air inlet channels 201 are arranged on the second membrane ring 200 along the circumferential direction, and combustible gas is charged into the deflagration driving section 1 through the first air inlet channels 201. The number of the first air inlet channels 201 may be three;

[0065] The first membrane ring 100, the second membrane ring 200 and the third membrane ring 300 are connected by concave and convex surfaces respectively, such as the second membrane ring 200 is provided with a first convex portion 202 on the side close to the first membrane ring 100, the second membrane ring 200 is provided with a second concave portion 211 on the side close to the third membrane ring 300, the first membrane ring 100 is provided with a first concave portion 101 on the side close to the second membrane ring 200, the third membrane ring 300 is provided with a second convex portion 302 on the side close to the second membrane ring 200, the first convex portion 202 is matched and connected with the first concave portion 101, the second concave portion 211 is matched and connected with the second convex portion 302, the first convex portion 202 is provided with a mixing channel 203 along the circumferential direction on the side close to the first membrane ring 100, and the multiple first air inlet channels 201 need to be merged into the mixing channel 203 before entering the deflagration driving section 1 to mix the combustible gases of different first air inlet channels 201;

[0066] A metal wire 204 is fixedly connected in the mixing channel 203. The metal wire 204 is spiral, so that the airflow generates turbulence when flowing through the spiral metal wire 204, thereby strengthening the mixing of the components. For example, the fuel, the oxidant and the inert gas flow into the mixing channel 203 through the first air inlet channel 201 respectively. The spiral metal wire 204 generates turbulence when the airflow flows through, thereby strengthening the mixing of the fuel, the oxidant and the inert gas. In addition, the spiral outer diameter of the metal wire 204 can be 0.5 mm larger than the width of the mixing channel 203, and the metal wire 204 can be directly clamped in the mixing channel 203 by utilizing its elasticity; of course, the outer diameter of the metal wire 204 can also be made less than or equal to the width of the mixing channel, and the metal wire 204 can be directly bonded to the mixing channel 203.

[0067] Each first air intake channel 201 is connected to the mixing channel 203, such that the fuel, the oxidant and the inert gas enter the mixing channel 203 through the first air intake channel 201 to be mixed;

[0068] The mixing channel 203 is connected to the inside of the deflagration driving section 1 through the gas outlet channel 205. The gas outlet channel 205 has a mixed gas outlet 206. The mixed gas outlet 206 is located on the inner wall of the second membrane ring. The number of the gas outlet channel 205 is 1. The mixed gas in the mixing channel 203 enters the deflagration driving section 1 through the gas outlet channel 205. Compared with the method of the prior art in which each driving gas is respectively filled into the pipeline of the deflagration driving section 1 and then mixed, the present invention enables each driving gas to be mixed in the mixing channel 203 first and then enter the pipeline of the deflagration driving section 1, which can significantly improve the uniformity of the mixed gas. In addition, since the diaphragm 5 is arranged between the second membrane ring and the third membrane ring, the mixed gas outlet 206 is relatively close to the diaphragm 5, which can reduce the four corners of the gas flow and ensure the uniformity of the gas in the deflagration driving section 1.

[0069] The mixing channel 203 has an air inlet 207, a mixing portion 208 and an air outlet 209. The air inlet 207 is located at one end of the mixing channel 203, and the air inlet 207 corresponds to each first air inlet channel 201. The air outlet 209 is located at the other end of the mixing channel 203, and the air outlet 209 corresponds to the air outlet channel 205. The mixing portion 208 is located between the air inlet 207 and the air outlet 209. The spiral metal wire 204 can be fixed to the mixing portion 208 to facilitate more effective air mixing. The mixing channel 203 occupies 4 / 5 of the circumference of the first convex portion 202.

[0070] The end of the air inlet 207 close to the mixing portion 208 is connected to the end of the air outlet 209 close to the mixing portion 208 through the mixing portion 208, and a blocking portion 210 is provided between the end of the air inlet 207 away from the mixing portion 208 and the end of the air outlet 209 away from the mixing portion 208, and the blocking portion 210 occupies 1 / 5 of the circumference of the first convex portion 202;

[0071] A second air inlet channel 301 is provided on the third membrane ring 300. The number of the second air inlet channel 301 can be one. The second air inlet channel 301 is linear. The second air inlet channel 301 is connected to the driven section 2. The test gas, such as air or inert gas, is flushed into the driven section 2 through the second air inlet channel 301.

[0072] During specific use, the first membrane ring 100 is first connected to the deflagration driving section 1, the third membrane ring 300 is connected to the driven section 2, and the second membrane ring 200 is clamped between the first membrane ring 100 and the third membrane ring 300, wherein the diaphragm 5 is installed between the second membrane ring 200 and the third membrane ring 300; secondly, each driving gas is connected through each first air inlet channel 201, and each driving gas is filled into the mixing channel 203 through the first air inlet channel 201 for mixing, and the mixed combustible mixed gas enters the deflagration driving section 1 through the air outlet channel 205; the test gas, such as air or inert gas, is connected through the second air inlet channel 301, and the test gas enters the driven section 2 through the air outlet channel 205.

[0073] Compared with the prior art, the double-sided air-filled premixed film clamping device for a coaxial cylindrical deflagration drive device provided by the present invention achieves at least the following beneficial effects:

[0074] First, in the prior art, independent inflation holes are simply set on the tube wall, and each driving gas enters the deflagration driving section pipeline separately and then mixes, resulting in poor mixing effect. In the present invention, each driving gas first flows into the mixing channel of the second clamp before entering the deflagration driving section. Since a spiral metal wire is fixed in the mixing channel, turbulence can be generated when the airflow passes through, thereby strengthening the mixing of the components. After that, the mixed gas flows into the deflagration driving section through the gas outlet channel, and the uniformity of the mixed gas is significantly improved;

[0075] Second, compared with the prior art, there is no special requirement for the position of the air inlet in the inflation structure, and the mixed gas outlet in the present invention is located very close to the diaphragm, which can significantly reduce the dead angle of gas flow and ensure the consistency of gas component distribution in the pipelines of the driving section 1 and the driven section 2.

[0076] In some optional embodiments, continue to refer to Figure 5 As shown, the mixed gas outlet 206 is close to one side of the diaphragm 5. By placing the mixed gas outlet 206 close to the diaphragm 5, the dead angle of gas flow is significantly reduced, and the gas purity in the deflagration driving section 1 is more effectively guaranteed.

[0077] In some optional embodiments, continue to refer to Figure 7 As shown, the air outlet channel 205 includes a first air inlet section 212 and a first air outlet section 213 connected to the first air inlet section 212. The first air inlet section 212 is located on the side of the air outlet channel 205 close to the mixing channel 203, and the first air outlet section 213 is located on the side of the air outlet channel 205 away from the mixing channel 203. The first air inlet section 212 is connected to the mixed air outlet 206 through the first air outlet section 213, and the angle between the first air inlet section 212 and the first air outlet section 213 is 80°-100°.

[0078] Specifically, the air outlet channel 205 includes a first air inlet section 212 and a first air outlet section 213, the first air inlet section 212 and the first air outlet section 213 are connected, the first air inlet section 212 is located on the side of the air outlet channel 205 close to the mixing channel 203, and the first air outlet section 213 is located on the side of the air outlet channel 205 away from the mixing channel 203, the first air inlet section 212 is connected to the mixed air outlet 206 through the first air outlet section 213, and the angle between the first air inlet section 212 and the first air outlet section 213 can be designed to be between 80°-100°, which can be completed by conventional mechanical processing means, without the need for casting or 3D printing, thereby reducing costs and improving strength. The angle between the first air inlet section 212 and the first air outlet section 213 can be 90°, that is, the angle between the first air inlet section 212 and the first air outlet section 213 is designed to be a right angle, which is better processed.

[0079] In some optional embodiments, continue to refer to Figure 5 As shown, the first air inlet channel 201 includes a second air inlet section 214 and a second air outlet section 215 connected to the second air inlet section 214, and the second air inlet section 214 is located on the side of the first air inlet channel 201 away from the mixing channel 203; the second air outlet section 215 is located on the side of the first air inlet channel 201 close to the mixing channel 203, and the angle between the second air inlet section 214 and the second air outlet section 215 is 80°-100°.

[0080] Specifically, the first air inlet channel 201 includes a second air inlet section 214 and a second air outlet section 215, and the second air inlet section 214 and the second air outlet section 215 are connected. The second air inlet section 214 is located on the side of the first air inlet channel 201 away from the mixing channel 203; the second air outlet section 215 is located on the side of the first air inlet channel 201 close to the mixing channel 203. The angle between the second air inlet section 214 and the second air outlet section 215 is 80°-100°, which can be completed by conventional mechanical processing means without the need for casting or 3D printing, thereby reducing costs and improving strength. The angle between the second air inlet section 214 and the second air outlet section 215 can be designed to be 90°, which makes it easier to process.

[0081] Fig.11 It is a schematic structural diagram of a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel provided by an embodiment of the present invention; Fig.12 yes Fig.11 A magnified view of the structure at B in the middle; Fig.13 yes Fig.11 A magnified diagram of the structure of the discharge system; Fig.14 is a logic block diagram of a discharge system provided by an embodiment of the present invention. Figure 11-Figure 14 As shown, this embodiment provides a coaxial cylindrical deflagration drive device for a shock tube / wind tunnel, comprising a deflagration drive section 1, a driven section 2, a double-sided gas-filled premixed film clamping device 1000, a blind plate 14, and a discharge system 7, wherein one end of the deflagration drive section 1 is connected to the driven section 2 through the double-sided gas-filled premixed film clamping device 1000, and the other end is connected to the blind plate 14;

[0082] The deflagration driving section 1 is a straight tube of equal cross section, and a first electrode 11 and a second electrode 12 extending along a radial direction Y are plugged 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, and an ignition wire 13 extending along an axial direction X is electrically connected between the first electrode 11 and the second electrode 12, and the axial direction X is the direction of the axial centerline from the deflagration driving section 1 to the driven section 2, and the radial direction Y intersects the axial direction X;

[0083] 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 0.5 cm-20 cm;

[0084] The deflagration driving section 1 is provided with an opening 8 that matches the first electrode 11 and the second electrode 12, and a sealing ring 81 is provided on the contact surface between the first electrode 11 and the second electrode 12 and the opening 8;

[0085] The deflagration driving section 1 is filled with a combustible mixed gas;

[0086] The discharge system 7 includes a high-voltage capacitor 71, an ignition switch 720 and a unloading switch 730. The ignition circuit 72 is formed by the positive electrode 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 electrode of the high-voltage capacitor 71; the unloading circuit 73 is formed by the positive electrode of the high-voltage capacitor 71, the unloading switch 730 and the negative electrode of the high-voltage capacitor 71; the ignition circuit 72 is connected in parallel with the unloading circuit 73, and the high-voltage capacitor 71 is used to store high voltage electricity and discharge it to the ignition wire.

[0087] Specifically, the coaxial cylindrical deflagration drive device for shock tube / wind tunnel comprises 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 plate 14.

[0088] The double-sided air-filled premixed film clamping device 1000 is the double-sided air-filled premixed film clamping device 1000 for the coaxial cylindrical deflagration drive device. The diaphragm 5 is located between the second film clamping ring 200 and the third film clamping ring 300. The deflagration drive section 1 is separated from the driven section 2 by the diaphragm 5. The driven section 2 is connected to the test section 4 through the nozzle 3. The blind plate 14 is a flange cover. The blind plate 14 is used to block the end of the deflagration drive section 1. There is no need to use a traditional explosion unloading section and set a diaphragm between the explosion unloading section and the deflagration drive section, which is not only conducive to reducing the occupied space area, but also can reduce costs.

[0089] A first electrode 11 and a second electrode 12 extending along a radial direction Y are plugged into the deflagration driving section 1, the first electrode 11 is located on the side of the deflagration driving section 1 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, that is, the first electrode 11 and the second electrode 12 are plugged into the two ends of the deflagration driving section 1; an ignition wire 13 extending along an axial direction 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 axial centerline of the driven section 2, the radial direction Y intersects the axial direction X, optionally, the ignition wire 13 can be made of any metal material selected from copper, silver, nickel-chromium, tungsten and alloys, and the length of the ignition wire 13 can be adjusted according to the length of the deflagration driving section 1;

[0090] 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 0.5 cm, breakdown may occur, resulting in equipment damage or endangering personnel safety; if the lengths of L1 and L2 are greater than 20 cm, it may cause unstable combustion of the combustible mixture in the deflagration driving section 1. Therefore, the lengths of L1 and L2 are limited to 0.5 cm-20 cm, which not only makes the ignition wire 13 as long as possible in the axial direction in the deflagration driving section, which can further make the combustible mixture in the deflagration driving section 1 burn more fully, but also avoids the distance between the first electrode 11 and the end of the deflagration driving 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;

[0091] Fig.12 yes Fig.11 A magnified view of the structure at B in the middle; Fig.11 The 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 match the first electrode 11 and the second electrode 12. Fig.12 In order to show the opening 8 in the figure, the aperture of the opening 8 is drawn 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 first electrode 11 and the second electrode 12 are conveniently plugged into the combustion driving section 1 through the opening 8. In order to ensure the sealing inside the deflagration driving section 1, a sealing ring 81 is provided 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 provided on the contact surface of the deflagration driving section 1 where the second electrode 12 contacts the opening 8;

[0092] The deflagration driving section 1 is filled with a combustible mixed gas through the first air inlet channel 201 on the second membrane ring 200. The combustible mixed gas may include fuel, oxidant and inert gas, wherein 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 gas or carbon dioxide, or other gases that do not participate in the combustion reaction; the ratio of fuel: oxidant: inert gas may be 1:1:1, the ratio of fuel: oxidant: inert gas may be 2:1:1, and the ratio of fuel: oxidant: inert gas may be 2:1:7. Of course, the ratio of fuel, oxidant and inert gas is set according to the experimental requirements; the driven section 2 is filled with a test gas, such as air or inert gas, through the second air inlet channel 301 on the third membrane ring 300;

[0093] The discharge system 7 includes a high-voltage capacitor 71, an ignition switch 720 and a discharge switch 730. The positive electrode 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 electrode of the high-voltage capacitor 71 constitute an ignition circuit 72; the positive electrode of the high-voltage capacitor 71, the discharge switch 730 and the negative electrode of the high-voltage capacitor 71 constitute a discharge circuit 73. The ignition circuit 72 and the discharge circuit 73 are connected in parallel. The high-voltage capacitor 71 is used to store high voltage electricity.

[0094] After the high-voltage capacitor 71 is charged, the ignition switch 720 is closed first, and 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 poles of the high-voltage capacitor 71, and the charge in the high-voltage capacitor 71 is instantly returned to the high-voltage capacitor 71 through the unloading circuit 73, completing the unloading. The above-mentioned predetermined time can be 5-30 milliseconds.

[0095] The assembly sequence of the coaxial cylindrical deflagration drive for shock tube / wind tunnel is as follows:

[0096] Providing a deflagration drive section 1;

[0097] First, an opening 8 for placing the first electrode 11 and the second electrode 12 is provided on the deflagration driving section 1; secondly, a sealing ring 81 is installed on the contact surface of the first electrode 11 and the second electrode 12 with the opening 8, and the first electrode 11 and the second electrode 12 are inserted into the opening 8, 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. After the first electrode 11 and the second electrode 12 are inserted, an ignition wire 13 extending along the axial direction X is connected between the first electrode 11 and the second electrode 12;

[0098] The driven section 2 is installed at one end of the deflagration driving section 1 through a double-side gas-filled premixed clamping device 1000, a diaphragm 5 is installed between the second clamping membrane ring 200 and the third clamping membrane ring 300, and a blind plate 14 is installed at the other end of the deflagration driving section 1;

[0099] The driving gas is charged into the deflagration driving section 1 through the first air inlet channel 201, and the test gas is charged into the driven section 2 through the second air inlet channel 301;

[0100] Connect the discharge system 7, and make the positive electrode 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 electrode of the high-voltage capacitor 71 form an ignition circuit 72; the positive electrode of the high-voltage capacitor 71, the unloading switch 730 and the negative electrode of the high-voltage capacitor 71 form an unloading circuit 73; the ignition circuit 72 and the unloading circuit 73 are connected in parallel.

[0101] Assembling the coaxial cylindrical deflagration drive device for shock tube / wind tunnel according to the above assembly sequence can not only better plug the first electrode and the second electrode and make the position of the ignition wire 13 more accurately arranged, but also avoid leakage of combustible mixture, ensure personal safety, and facilitate operation.

[0102] 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 driving gas can be filled into the deflagration driving section 1, as follows:

[0103] First, providing a deflagration drive section 1;

[0104] Second, first, an opening 8 for placing the first electrode 11 and the second electrode 12 is opened on the deflagration driving section 1; secondly, the first electrode 11 and the second electrode 12 are inserted into the opening 8, 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. After the first electrode 11 and the second electrode 12 are inserted, a sealing ring 81 is installed on the contact surface of the first electrode 11 and the second electrode 12 with the opening 8; an ignition wire 13 extending along the axial direction X is connected between the first electrode 11 and the second electrode 12;

[0105] Third, the driven section 2 is installed at one end of the deflagration driving section 1 through the double-side inflation premixing clamping device 1000, the diaphragm 5 is installed between the second clamping ring 200 and the third clamping ring 300, and the blind plate 14 is installed at the other end of the deflagration driving section 1;

[0106] Fourth, connect the discharge system 7, and make the positive electrode 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 electrode of the high-voltage capacitor 71 form an ignition circuit 72; make the positive electrode of the high-voltage capacitor 71, the unloading switch 730 and the negative electrode of the high-voltage capacitor 71 form an unloading circuit 73; connect the ignition circuit 72 and the unloading circuit 73 in parallel;

[0107] Fifth, the driving gas is charged into the deflagration driving section 1 through the first air inlet passage 201 , and the test gas is charged into the driven section 2 through the second air inlet passage 301 .

[0108] It should be noted that: first, a deflagration driving section 1 is provided; second, first, an opening 8 for placing a first electrode 11 and a second electrode 12 is provided on the deflagration driving section 1; secondly, a sealing ring 81 is installed on the contact surface of the first electrode 11 and the second electrode 12 with the opening 8, and the first electrode 11 and the second electrode 12 are inserted into the opening 8, 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, and after the first electrode 11 and the second electrode 12 are inserted, an ignition wire 13 extending along the axial direction X is connected between the first electrode 11 and the second electrode 12; third, the driven section 2 is installed at one end of the deflagration driving section 1 through a double-sided inflation premixing film clamping device 1000, a diaphragm 5 is installed between the second film clamping ring 200 and the third film clamping ring 300, and a blind plate 14 is installed at the other end of the deflagration driving section 1; the assembly sequence of the above three steps is irreversible, that is, the above assembly sequence cannot be reversed, and it cannot be implemented after reversal.

[0109] The working principle is as follows: there is an ignition wire 13 arranged along the axial direction X in the deflagration driving section 1. 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. A high voltage of thousands to tens of thousands of volts is applied to both ends of the ignition wire 13. At the moment when the ignition switch 720 is powered on, the ignition wire 13 is heated violently, and the driving gas near the ignition wire 13 is ignited within a microsecond. After ignition, a columnar flame surface is formed and expands radially; The ignition wire 13 is strictly coaxial with the pipeline of the deflagration driving section 1 to ensure that they are burned out simultaneously at all locations along the axial direction; 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 removed before the end of combustion. Therefore, after a predetermined time, the unloading switch 730 is closed to short-circuit the positive and negative poles of the high-voltage capacitor 71. The charge in the high-voltage capacitor 71 is instantly returned to the high-voltage capacitor 71 via the unloading circuit to complete the unloading, thereby preventing the combustion products from breaking down near the positive pole of the high-voltage capacitor 71 and causing a safety accident.

[0110] It should be noted that: the traditional detonation driving technology requires the formation of a detonation wave that propagates axially in the driving section pipeline, while the deflagration driving technology adopted in the present invention is to ignite the gas in the pipeline of the deflagration driving section 1 simultaneously along the axial direction, complete the combustion in a deflagration rather than a detonation manner, and end the combustion simultaneously along the axial direction X.

[0111] Usually the effective working time of a shock tube / wind tunnel is roughly in the order of a few milliseconds to 100 milliseconds. In order to provide accurate test conditions, it is necessary to strictly ensure that the driving gases in the deflagration driving section are ignited and burned out at the same time.

[0112] It can be seen from the above embodiments that the coaxial cylindrical deflagration drive device for shock tube / wind tunnel provided by the present invention achieves at least the following beneficial effects:

[0113] First, in the prior art, a detonation wave propagating in the axial direction is formed in the driving section pipeline by detonation driving. Since the extremely high pressure peak of the detonation wave cannot be fully used for driving, the effective pressure provided by the detonation driving is much lower than the pressure limit of the equipment. In the present invention, detonation is replaced by deflagration, and there is no pressure peak in the detonation. The combustion pressure can be 100% used to compress the test gas, thereby increasing the pressure of the test gas;

[0114] Second, the mixture ratio limit of deflagration is much wider than that of detonation, and the temperature and sound speed range of the driving gas is larger. Therefore, the corresponding total temperature range of the test gas is also larger than that of detonation drive.

[0115] Third, in the prior art, independent inflation holes are simply set on the tube wall, and each driving gas enters the deflagration driving section pipeline separately and then is mixed. In the present invention, each gas is first merged into the mixing channel of the second clamping member before entering the deflagration driving section. Since a spiral metal wire is fixed in the mixing channel, turbulence can be generated when the airflow flows through, thereby strengthening the mixing of each component. After that, the mixed gas flows into the deflagration driving section through the gas outlet channel, which significantly improves the uniformity of the mixed gas.

[0116] Fourth, compared with the prior art inflation structure which has no special requirements for the position of the air inlet, the mixed gas outlet of the present invention is located on the inner wall of the second clamping membrane ring, close to the position of the diaphragm, which can reduce the dead angle of gas flow and improve the spatial distribution consistency of the mixed gas;

[0117] Fig.15 It is a schematic diagram of the structure of a shock tube / wind tunnel provided in an embodiment of the present invention; the embodiment of the present invention also 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.

[0118] Although some specific embodiments of the present invention have been described in detail by way of example, it will be appreciated by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device, characterized in that: It comprises a first clamping membrane ring, a second clamping membrane ring and a third clamping membrane ring, wherein the first clamping membrane ring is connected to the deflagration driving section, the third clamping membrane ring is connected to the driven section, and the second clamping membrane ring is located between the first clamping membrane ring and the third clamping membrane ring; A diaphragm is provided between the second clamping membrane ring and the third clamping membrane ring; At least two first air inlet channels are arranged on the second clamping membrane ring along the circumferential direction; A first concave portion is provided on one side of the first clamping membrane ring close to the second clamping membrane ring; A first convex portion matching with the first concave portion is disposed on one side of the second clamping membrane ring close to the first clamping membrane ring, the first concave portion is connected to the first convex portion, and a mixing channel along the circumferential direction is disposed on the first convex portion; A metal wire is arranged in the mixing channel, and the metal wire is in a spiral shape; Each of the first air intake channels is in communication with the mixing channel; The mixing channel is connected to the inside of the deflagration driving section through an outlet channel, and the outlet channel has an air mixing outlet, and the air mixing outlet is located on the inner wall of the second clamping membrane ring; The mixing channel comprises an air inlet, a mixing portion and an air outlet, wherein the air inlet is located at one end of the mixing channel, the air outlet is located at the other end of the mixing channel, and the mixing portion is located between the air inlet and the air outlet; The end of the air inlet close to the mixing portion is connected to the end of the air outlet close to the mixing portion through the mixing portion, and a blocking portion is provided between the end of the air inlet away from the mixing portion and the end of the air outlet away from the mixing portion; The third clamping membrane ring is provided with a second air inlet channel, and the second air inlet channel is communicated with the driven section.

2. The double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device according to claim 1, characterized in that: The mixed gas outlet is close to one side of the diaphragm.

3. The double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device according to claim 1, characterized in that: The air outlet channel includes a first air inlet section and a first air outlet section connected to the first air inlet section, the first air inlet section is located on a side of the air outlet channel close to the mixing channel, the first air outlet section is located on a side of the air outlet channel away from the mixing channel, the first air inlet section is connected to the mixed air outlet through the first air outlet section, and the angle between the first air inlet section and the first air outlet section is 80°-100°.

4. The double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device according to claim 1, characterized in that: The first air inlet channel includes a second air inlet section and a second air outlet section connected to the second air inlet section, the second air inlet section is located close to the side of the first air inlet channel away from the mixing channel; the second air outlet section is located close to the side of the mixing channel away from the first air inlet channel, and the angle between the second air inlet section and the second air outlet section is 80°-100°.

5. The double-side inflation premixing film clamping device for a coaxial cylindrical deflagration drive device according to any one of claims 1 to 4, characterized in that: The metal wire is located in the mixing portion.

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