Magnetic drive valve structure for micropores in expansion section of permeable spray pipe
By designing a magnetic drive valve structure on the expansion section of the permeable nozzle, using the magnetic drive technology of NdFeB permanent magnet and arc-shaped sheet, the micro-holes are closed at a high altitude, solving the problem of gas leakage and improving the altitude of the nozzle The performance and maintain low-altitude thrust compensation capability, achieving the improvement of full ballistic performance.
Patent Information
- Application Number
- CN202421155205.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-24
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2034-05-24
AI Technical Summary
A small amount of gas leaks out when the permeable nozzle is flying at high altitude, resulting in poor thrust performance at high altitude.
A magnetically driven valve structure is designed, using neodymium iron boron permanent magnet and arc-shaped plate to form a rotating section and a fixed section on the permeable section, and the micro-holes are closed at a high altitude through the magnetically driven valve to prevent gas leakage.
The small holes in the permeable section are effectively closed, which improves high-altitude performance, increases the effective working airspace of the nozzle, and does not affect the thrust compensation performance at low altitude, achieving an improvement in full ballistic performance.
Smart Images
Figure CN222208105U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of aerospace, and in particular relates to a magnetic force driven valve structure for micropores of a permeable nozzle expansion section. Background Art
[0002] The altitude non-adaptive loss of rocket engine nozzles can reach 15% of the total energy loss of the engine, which greatly restricts the volatilization of the nozzle effect. In order to improve the thrust performance of rocket engine nozzles and compensate for the thrust performance loss caused by the change of back pressure during its operation, altitude compensation nozzles have received extensive attention from the scientific and engineering communities. Among them, the permeable nozzle is a new type of altitude compensation nozzle with the characteristics of no moving parts, continuous altitude compensation, and flow self-regulation. When the flight altitude is low, the pressure difference between the inside and outside of the nozzle wall is large, and the external high-pressure atmosphere enters the nozzle through the permeable section, increasing the pressure on the inner wall of the nozzle, slowing down or improving the over-expansion phenomenon inside the large expansion ratio nozzle, thereby increasing the engine thrust. The pressure difference between the inside and outside of the nozzle changes with the flight altitude, but the permeable nozzle always adjusts the pressure on the inner wall of the nozzle through the pressure difference, thereby changing the internal flow field structure of the nozzle and matching the flow state in the nozzle with the flight altitude. The permeable nozzle uses this adaptive adjustment mechanism to obtain continuous altitude compensation capability. When the flight altitude exceeds a certain height, the external atmospheric pressure is lower than the gas pressure in the permeable nozzle, and a small amount of gas will leak out of the nozzle, which will have a negative impact on the high-altitude thrust of the nozzle. Utility Model Content
[0003] The purpose of the utility model is to solve the problem that a small amount of gas leaks out of the permeable nozzle when the nozzle is at high altitude, resulting in poor high-altitude thrust performance. A magnetically driven valve structure for the micropores of the expansion section of the permeable nozzle is provided. The setting of the magnetically driven valve structure enables the permeable nozzle to close the small holes at the permeable section under high-altitude flight conditions, thereby improving the high-altitude performance of the permeable nozzle and increasing the effective working airspace of the permeable nozzle.
[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is as follows:
[0005] A magnetically driven valve structure for a micropore in a permeable nozzle expansion section, the magnetically driven valve structure comprising a nozzle housing, a permeable section, a flat head positioning pin hole, a rotating section, a truncated cone micropore, a NdFeB permanent magnet, a fixed section, a flat head positioning pin, and a permeable micropore, such as Figure 1 and Figure 2 As shown;
[0006] A composite material of a certain thickness is cut off along the outer side of the permeable section of the permeable nozzle (made of non-metallic materials, such as C / SIC ceramic-based composite materials) to form a groove on the outer side, so that the wall of the permeable section is thinner than the wall of other parts of the nozzle. On this basis, two arc-shaped pieces with the same material and shape as the cut part of the nozzle are installed on the permeable section. The two arc-shaped pieces fit tightly with the permeable nozzle. The longer arc-shaped piece is not fixed to the permeable section and can rotate around the permeable section, which is called the rotating section; the shorter arc-shaped piece is called the fixed section.
[0007] A certain thickness of material is cut off from the outer side of the upper edge of the permeable section to form a groove; the groove is used to set the rotating section and the fixed section, the rotating section can rotate around the permeable section, and the fixed section is fixed relative to the permeable section; the fixed section and the permeable section can be formed in one piece, or the fixed section can be produced first and then fixed to the permeable section;
[0008] There is a certain gap between the rotating section and the fixed section, and a NdFeB permanent magnet is installed on both sides of the gap at a certain angle. The permanent magnets are embedded in the rotating section and the fixed section and staggered with each other; the magnetic poles on both sides of the gap between the fixed section and the rotating section are different; there must be a certain gap between the rotating section and the fixed section, because if the fixed section and the rotating section are in contact, the rotating section may not rotate to the expected angle under the action of friction. Of course, the width should be as small as possible, and it should be ensured that the force between the magnets will not be significantly weakened due to the distance. The angle between adjacent permanent magnets is not fixed, such as 120°, 90°, 60°, etc., but it is necessary to ensure that each pair of magnets will not affect each other, and the number of pairs of magnets can be appropriately increased.
[0009] The rotating section is provided with truncated cone micropores, and the permeable section is provided with permeable micropores, and the truncated cone micropores correspond to the permeable micropores one by one to ensure smooth air circulation;
[0010] A circle of flat-head locating pin holes are opened on one side of the rotating section and the permeable section near the throat, and they correspond one to one, for installing flat-head locating pins; the flat-head locating pins penetrate the rotating section and the permeable section, and the two do not rotate relative to each other when penetrated.
[0011] Furthermore, the staggered interval of each pair of matched NdFeB permanent magnets is less than 10°, ensuring that after rotation, the holes of the permeable section and the rotating section are completely disconnected, and the gas cannot leak. Figure 6 shown.
[0012] Furthermore, the number and size of the truncated cone micropores are the same as those of the permeable section micropores and correspond one to one, such as Figure 5 shown.
[0013] Furthermore, if Figure 4As shown, the length of the flat-head locating pin (excluding the head) is equal to or less than the thickness of the nozzle shell, and the purpose of setting the length is to make the internal surface as smooth as possible.
[0014] Furthermore, hot melt adhesive suitable for bonding metal materials is coated between the flat head locating pin and the flat head locating pin hole to ensure that the flat head locating pin will not fall off during the transportation and installation of the nozzle.
[0015] Furthermore, the permeable section and the rotating section are provided with a row of micro holes and a flat head positioning pin hole every 10°.
[0016] Compared with the prior art, the beneficial effects of the utility model are:
[0017] 1. Compared with the existing permeable nozzle, the permeable nozzle adopting the magnetically driven valve structure can close the permeable section under high-altitude flight conditions, prevent the leakage of gas, and avoid the loss of high-altitude performance, thus having better high-altitude flight capability than the permeable nozzle without this structure.
[0018] 2. Under low-altitude flight conditions, the permeable section can work normally, and this structure does not affect the low-altitude thrust compensation performance of the permeable nozzle.
[0019] 3. The high altitude micropore closing technology of the permeable nozzle using the magnetically driven valve structure is a passive regulation technology. The closing of the valve is completely driven by the magnetic force of the permanent magnet and does not require an additional control system or actuator.
[0020] 4. The performance of the permeable nozzle using this valve structure is close to that of the original permeable nozzle in the low altitude section, and is better than the original permeable nozzle in the high altitude section, and has better overall ballistic performance.
[0021] 5. This structure mainly changes the external profile of the nozzle and has little effect on the internal profile of the nozzle, which can ensure the smoothness of the internal profile and will not produce additional flow losses. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the 1 / 8 structure of the permeable nozzle of the utility model.
[0023] Figure 2 This is a schematic diagram of the 1 / 8 structure of the permeable nozzle body.
[0024] Figure 3 It is a schematic diagram of the 1 / 8 structure of the rotating section of the permeable nozzle.
[0025] Figure 4 This is a schematic diagram of a flat head locating pin.
[0026] Figure 5 This is a 1 / 8 model wireframe diagram of a permeable nozzle in low altitude working mode.
[0027] Figure 6 This is a 1 / 8 model wireframe diagram of a permeable nozzle in high altitude working mode.
[0028] Among them, 1-nozzle shell, 2-permeable section, 3-flat head positioning pin hole, 4-rotating section, 5-truncated cone microhole, 6-NdFeB permanent magnet, 7-fixed section, 8-flat head positioning pin, 9-permeable microhole. DETAILED DESCRIPTION
[0029] The technical solution of the utility model is further explained below in conjunction with the accompanying drawings and embodiments, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the utility model without departing from the spirit and scope of the technical solution of the utility model should be included in the protection scope of the utility model.
[0030] Neodymium iron boron permanent magnet, which is a tetragonal crystal composed of neodymium, iron, boron and other elements, can absorb weights equivalent to 640 times its own weight. Neodymium iron boron permanent magnets are suitable for use in the aerospace field to reduce the weight of aircraft due to their small size, strong magnetism and good heat resistance. On the premise of ensuring that the contact surface of the rotating section and the permeable section has a certain degree of smoothness, the utility model gives priority to the use of neodymium iron boron permanent magnets. If a group of permanent magnets is set every 90°, 8 neodymium iron boron permanent magnets can generate enough torque to make the rotating section rotate relative to the nozzle.
[0031] Embodiment 1:
[0032] The nozzle model dimensions of the utility model are: nozzle contraction section 500mm, nozzle expansion section 1600mm, throat diameter 260mm, expansion ratio 30, permeable section length 700mm, permeable section and rotating section are provided with a row of micro holes and a positioning pin hole every 10°, nozzle thickness 56mm, positioning pin length 56mm (excluding the head). The size of the NdFeB permanent magnet is close to a cuboid of 40mm×50mm×30mm.
[0033] The magnetically driven valve structure includes a nozzle housing 1, a permeable section 2, a flat head positioning pin hole 3, a rotating section 4, a truncated cone microhole 5, a permanent magnet 6, a fixed section 7, a flat head positioning pin 8, and a permeable microhole 9. Figure 1 and Figure 2 As shown;
[0034] A composite material of a certain thickness is cut off along the outer side of the permeable section of the permeable nozzle (made of non-metallic materials, such as C / SIC ceramic-based composite materials) to form a groove on the outer side, so that the wall of the permeable section is thinner than the wall of other parts of the nozzle. On this basis, two arc-shaped pieces with the same material and shape as the cut part of the nozzle are installed on the permeable section. The two arc-shaped pieces fit tightly with the permeable nozzle. The longer arc-shaped piece is not fixed to the permeable section and can rotate around the permeable section, which is called the rotating section; the shorter arc-shaped piece is called the fixed section.
[0035] A certain gap is left between the rotating section 4 and the fixed section 7, and a NdFeB permanent magnet 6 is installed on both sides of the gap at a certain angle. The permanent magnets 6 are embedded in the rotating section 4 and the fixed section 7 and staggered with each other; the magnetic poles on both sides of the gap between the fixed section 7 and the rotating section 4 are different; the angle between adjacent permanent magnets is 90°.
[0036] The rotating section 4 is provided with truncated cone micropores 5, and the permeable section 2 is provided with permeable micropores 9. The number and size of the truncated cone micropores 5 are the same as those of the micropores in the internal permeable section 2 and correspond one to one to ensure smooth air circulation. Figure 5 shown.
[0037] A circle of flat-head positioning pin holes 3 are provided on one side of the rotating section 4 and the permeable section 2 near the throat, and the holes are corresponding to each other, for installing flat-head positioning pins 8; the flat-head positioning pins 8 penetrate the rotating section 4 and the permeable section 2, and the two do not rotate relative to each other during penetration. The permeable section 2 and the rotating section 4 are provided with a row of micro-holes and a flat-head positioning pin hole 3 every 10°.
[0038] The fixed section 7 and the rotating section 4 (such as Figure 3 As shown in the figure, the rotating section 4 is installed on the permeable section 2 and a certain gap is maintained (the rotating section 4 is not fixed, but due to the special structure of the truncated cone, it will not slide along the nozzle) to prevent the NdFeB permanent magnets 6 from contacting each other, which would result in the magnetic poles not being aligned under the action of friction. The rotating section 4 has a certain degree of smoothness with the nozzle body and the permeable section 2 to ensure that the eight NdFeB permanent magnets 6 can drive the rotating section 4 to rotate. The staggered interval of each matching pair of NdFeB permanent magnets 6 is less than 10° to ensure that after rotation, the holes of the permeable section 2 and the rotating section 4 are not connected at all, and the gas cannot leak. As shown in the figure, the rotating section 4 is installed on the permeable section 2 and the permeable section 4 is not fixed, which would prevent the gas from leaking. Figure 6 As shown. Figure 4 As shown, the length of the flat head positioning pin 8 (excluding the head) is equal to the thickness of the nozzle housing 1, and the purpose of setting the length is to make the internal profile as smooth as possible. Hot melt adhesive suitable for bonding metal materials is applied between the flat head positioning pin 8 and the flat head positioning pin hole 3 to ensure that the flat head positioning pin 8 will not fall off during the transportation and installation of the nozzle.
[0039] When working at low altitude, the ambient pressure is much greater than the pressure on the inner wall of the nozzle, and the outside atmosphere flows into the inside of the nozzle. At this time, the hot melt adhesive melts and falls off under the high temperature of the gas, but under the action of the internal and external pressure difference, the flat-head positioning pin 8 is still fixed in place, so that the rotating section 4 is fixed relative to the permeable section 2, and the truncated cone micropore 5 and the permeable micropore 9 remain connected, so that the outside air can smoothly enter the inside of the nozzle to achieve the penetration effect.
[0040] When working at high altitude, the gas in the nozzle expands, and the internal pressure of the nozzle is greater than the external environmental pressure. At this time, the flat-head positioning pin 8 is pushed out of the nozzle by the gas flow under the action of the internal and external pressure difference, and the rotating section 4 loses its constraint and rotates relative to the permeable section 2. When the magnetic poles of the NdFeB permanent magnets 6 on both sides are relative, the rotating section 4 loses the torque effect and stops rotating. At this time, the truncated cone micropores 5 and the permeable micropores 9 are no longer connected, and the internal gas cannot leak, reducing the high-altitude thrust loss of the nozzle. The simulation data is given below: the working conditions of the permeable nozzle at an altitude of 30km, with a total pressure of 3900000Pa and a total temperature of 3400K are simulated, wherein the working conditions of the permeable section indicate the opening of the small holes of the permeable section; when the permeable section is closed, the permeable section is calculated as the nozzle wall, simulating the working conditions when the small holes of the permeable section are closed (i.e., the working conditions of this invention). It can be seen from the table that the permeable section has better performance when it is closed at high altitude, indicating that this invention reduces the high-altitude thrust loss of the permeable nozzle.
[0041]
[0042] The above is the principle of the utility model. For those skilled in the art, the utility model can be modified and changed in various ways. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model, such as: appropriately increasing the number of permanent magnets; appropriately changing the size or type of permanent magnets; exchanging the relative position of the rotating section and the fixed section, etc., should be included in the protection scope of the utility model.
Claims
1. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section, characterized in that: The magnetic force driven valve structure comprises a nozzle housing (1), a permeable section (2), a flat head positioning pin hole (3), a rotating section (4), a truncated cone microhole (5), a permanent magnet (6), a fixed section (7), a flat head positioning pin (8), and a permeable microhole (9); A material of a certain thickness is cut off from the outer side of the upper edge of the permeable section (2) to form a groove; the groove is used to arrange the rotating section (4) and the fixed section (7); the rotating section (4) can rotate around the permeable section (2), and the fixed section (7) is fixed relative to the permeable section (2); A certain gap is left between the rotating section (4) and the fixed section (7), and a permanent magnet (6) is installed at a certain angle on both sides of the gap. The permanent magnets (6) are embedded in the rotating section (4) and the fixed section (7) and are staggered with each other; the magnetic poles on both sides of the gap between the fixed section (7) and the rotating section (4) are different from each other; The rotating section (4) is provided with a truncated cone micropore (5), and the permeable section (2) is provided with a permeable micropore (9), and the truncated cone micropore (5) corresponds to the permeable micropore (9) one by one; A circle of flat-head positioning pin holes (3) are provided on one side of the rotating section (4) and the permeable section (2) near the throat, and are in one-to-one correspondence, for installing flat-head positioning pins (8); the flat-head positioning pins (8) penetrate the rotating section (4) and the permeable section (2), and the two do not rotate relative to each other when penetrated.
2. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section according to claim 1, characterized in that: The staggered interval of each pair of matched NdFeB permanent magnets (6) is less than 10°.
3. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section according to claim 1, characterized in that: The number and size of the openings of the truncated cone micropores (5) are the same as those of the micropores of the permeable section (2) and correspond one to one.
4. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section according to claim 1, characterized in that: The length of the flat head positioning pin (8) is equal to or less than the thickness of the nozzle shell (1).
5. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section according to claim 1, characterized in that: Hot melt adhesive is applied between the flat head positioning pin (8) and the flat head positioning pin hole (3).
6. A magnetically driven valve structure for a micropore in a permeable nozzle expansion section according to claim 1, characterized in that: The permeable section (2) and the rotating section (4) are provided with a row of micro holes and a flat-head positioning pin hole (3) every 10 degrees.