Single-component micro-thruster based on MEMS technology
By using nitrous oxide as propellant and designing porous structures and iridium catalysts in the reaction chamber, the performance and cost balance problems of single-component microthrusts are solved, and efficient catalytic decomposition and energy savings are achieved.
Patent Information
- Application Number
- CN202422039629.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-07-08
- Estimated Expiration
- 2034-08-21
AI Technical Summary
Existing single-component microthrusts are difficult to achieve a balance between propellant safety, low cost and high performance, especially in terms of catalyst selection and structural design.
Nitrous oxide is used as propellant, and a multi-column and a Laval nozzle are designed to cover the iridium catalyst between multiple columns and the Laval nozzle in the reaction chamber of the thrust. The catalytic decomposition is combined with a heating wire. The reaction chamber is designed to be porous to improve catalytic efficiency.
The specific impulse and thrust of the thrust are achieved, energy saving, and the balance between propellant safety, low cost and high performance is solved.
Smart Images
Figure CN223072763U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of micro-thrusters, and particularly relates to a monopropellant micro-thruster based on MEMS technology. Background Art
[0002] With the continuous progress of space technology, the requirements for the performance of spacecraft are getting higher and higher, especially the demand for miniaturization of spacecraft. As one of the key technologies to achieve this goal, the development of micro-propulsion systems has received extensive attention. The development of MEMS technology provides new possibilities for the design and manufacture of micro-propulsion systems, enabling thrusters to have the advantages of low cost, light weight, small volume, and high integration.
[0003] Currently, thrusters based on MEMS processes are mainly micro-cold gas thrusters and micro-chemical thrusters. The specific impulse of micro-cold gas thrusters is lower than that of micro-chemical thrusters. Micro-chemical thrusters can significantly improve the specific impulse and thrust of thrusters by utilizing the chemical energy of the working medium. The main micro-chemical thrusters are solid micro-thrusters and monopropellant micro-thrusters. However, traditional solid micro-thrusters cannot adjust the magnitude of thrust, which limits their application scope to a certain extent.
[0004] Currently, the monopropellant micro-thrusters under research are difficult to achieve the balance of propellant safety, low cost, and high performance, that is, the selected catalyst is green, the manufacturing cost is low, the thrust is stable (in the millinewton level), and the power density is low.
[0005] Nitrous oxide (N2O), as a commonly used propellant, can decompose under the action of a catalyst and high temperature. Due to its self-decomposition characteristics (the decomposition reaction is an exothermic reaction, and once it occurs, it does not require continuous heating of the thruster and can self-sustain the decomposition), it can not only improve the specific impulse and thrust but also save energy.
[0006] Existing monopropellant micro-thrusters based on MEMS technology, although having many theoretical advantages, still have some limitations and challenges in practical applications. For example, some thrusters use highly toxic or environmentally harmful propellants, such as hydrazine (N2H4), which no longer meet modern space environmental protection standards. The most widely used high-concentration hydrogen peroxide solution (H2O2) decomposes into oxygen and water under the action of a catalyst, releasing heat energy to increase the thrust and specific impulse. However, if you want to maintain the decomposition process, the thruster needs to be continuously heated, that is, more energy needs to be provided, which undoubtedly increases the demand and consumption of energy. There are also a small number of thrusters that use HAN and ADN propellants to generate thrust by electrolytic decomposition of gas. However, as high-energy substances, these two propellants will face certain challenges when applied to MEMS thrusters.
[0007] In terms of structural design, for MEMS single-component microthrusters, most of them are in planar configurations, which are simple, easy to process, easy to assemble, and mass production can significantly reduce costs. For existing thrusters involving catalytic decomposition, some design cubic columns in the chamber and add catalysts on the surface of the cubic columns. Obviously, the contact area between the propellant and the catalyst is very limited. There are also those that directly add catalyst microparticles in the chamber, but they have high requirements for assembly. Summary of the Invention
[0008] The purpose of the present invention is to provide a single-component microthruster based on MEMS technology to solve the problem that it is difficult for existing single-component microthrusters to achieve a balance among the safety, low cost, and high performance of the propellant.
[0009] To solve the above technical problems, the present invention provides a single-component microthruster based on MEMS technology. The single-component microthruster is a thruster using nitrous oxide as the propellant. The single-component microthruster includes a thruster base, a heating wire partition, heating wires, and a thruster end cap. One surface of the thruster base is provided with a reaction chamber, and a gas inlet region and a Laval nozzle that are mutually communicated are arranged in the reaction chamber. Multiple columnar bodies are arranged at positions adjacent to the gas inlet region in the reaction chamber, and the multiple columnar bodies are arranged separately from each other. Between the multiple columnar bodies and the Laval nozzle, the surface of the reaction chamber is covered with a plurality of receiving holes, and iridium catalysts are filled in the plurality of receiving holes. The heating wire partition covers the reaction chamber, and the heating wire partition is provided with partition through holes that are communicated with the reaction chamber. The heating wires are arranged between the heating wire partition and the thruster end cap. The thruster end cap is provided with end cap through holes that are communicated with the partition through holes.
[0010] In one embodiment, in the direction from the gas inlet region to the Laval nozzle, the width dimension of the gas inlet region increases.
[0011] In one embodiment, the multiple columnar bodies are all in contact with the heating wire partition.
[0012] In one embodiment, the multiple columnar bodies are all cylindrical.
[0013] In one embodiment, the multiple columnar bodies are arranged in a staggered array.
[0014] In one embodiment, between the multiple columnar bodies and the Laval nozzle, the reaction chamber is provided with a perforated plate, and the plurality of receiving holes are all arranged on the perforated plate, and the region where the multiple columnar bodies are located is communicated with the Laval nozzle by the plurality of receiving holes.
[0015] In one embodiment, the receiving holes include a first receiving hole and a second receiving hole; a plurality of the first receiving holes communicate the region where the plurality of columnar bodies are located with the Laval nozzle; a plurality of the second receiving holes communicate with the plurality of the first receiving holes, and the plurality of the second receiving holes all face the heating wire partition plate.
[0016] In one embodiment, the materials of the thruster base, the heating wire partition plate and the thruster end cap are all silicon.
[0017] In one embodiment, the material of the heating wire is Pt (platinum).
[0018] The beneficial effects of the present utility model are as follows:
[0019] Since the single-component micro-thruster is a thruster using nitrous oxide as a propellant, and between the plurality of columnar bodies and the Laval nozzle, the surface of the reaction chamber is covered with a plurality of receiving holes, and iridium catalysts are filled in the plurality of receiving holes, so it can be decomposed under the action of the catalyst and high temperature, the reaction releases heat and self-sustains decomposition, realizing the improvement of specific impulse and thrust, and saving energy; and after the reaction chamber is designed to be porous, the efficiency of catalytic decomposition can be improved, thereby improving the specific impulse of the thruster, thus effectively solving the problem that it is difficult for the existing single-component micro-thruster to achieve the balance of propellant safety, low cost and high performance. Description of the Drawings
[0020] In order to more clearly illustrate the technical solutions of the present utility model, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.
[0021] Figure 1 is the structural schematic diagram provided by the embodiment of the present utility model;
[0022] Figure 2 is Figure 1 the disassembled structural schematic diagram of
[0023] Figure 3 is Figure 2 the enlarged structural schematic diagram of part A of
[0024] The reference numerals are as follows:
[0025] 10. Thruster base; 11. Reaction chamber; 12. Gas inlet region; 13. Laval nozzle; 14. Columnar body; 15. Receiving hole; 151. First receiving hole; 152. Second receiving hole; 16. Porous plate;
[0026] 20. Heating wire partition; 21. Partition through-hole;
[0027] 30. Heating wire;
[0028] 40. Thruster end cap; 41. End cap through-hole. Specific embodiments
[0029] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention.
[0030] The present invention provides a single-component micro-thruster based on MEMS technology, and its embodiment is as Figures 1 to 3 shown. The single-component micro-thruster is a thruster using nitrous oxide as a propellant. The single-component micro-thruster includes a thruster base 10, a heating wire partition 20, a heating wire 30, and a thruster end cap 40.
[0031] Regarding the thruster base 10, as Figures 1 to 3 shown, at this time, the material of the thruster base 10 is silicon, which is etched by MEMS process, and its external dimensions are 1mm * 15mm * 20mm, belonging to an integrally formed structure; a reaction chamber 11 is provided on one surface of the thruster base 10. In the illustrated direction, the reaction chamber 11 is provided on the upper surface of the thruster base 10. A gas inlet region 12 and a Laval nozzle 13 that are mutually communicated are provided in the reaction chamber 11. The gas inlet region is provided on the left side of the reaction chamber 11, and the Laval nozzle 13 is provided on the right side of the reaction chamber 11.
[0032] Among them, at this time, in the direction from the gas inlet region 12 to the Laval nozzle 13, the width dimension of the gas inlet region 12 increases, while in the region of the reaction chamber 11 adjacent to the Laval nozzle 13, the width dimension of this region gradually decreases.
[0033] In addition, multiple columnar bodies 14 are provided at the position of the reaction chamber 11 adjacent to the gas inlet region 12, and the multiple columnar bodies 14 are arranged separately; the shape of the columnar body 14 is not particularly limited. For example, the columnar body 14 can be a rectangular column, a triangular column, or other polygonal columns. In this embodiment, the multiple columnar bodies 14 are all cylindrical, which belongs to a better choice, not only facilitating processing but also having sufficient area to contact the propellant.
[0034] Similarly, there are no special restrictions on the arrangement of the columnar bodies 14, which can be regularly arranged or irregularly arranged; in this embodiment, multiple columnar bodies 14 are arranged in a staggered array. For example, after the columnar bodies 14 in the first row are arranged at equal intervals in a straight line direction, the columnar bodies 14 in the second row will be arranged at equal intervals in the same straight line direction, and the multiple columnar bodies 14 in the second row will respectively align with the spaces separated by the multiple columnar bodies 14 in the first row; with such a regular arrangement of the multiple columnar bodies 14, not only is the processing simple, but also it can ensure that the multiple columnar bodies 14 are fully and evenly distributed in the reaction chamber 11, so that the heat transfer efficiency is consistent and high everywhere inside the reaction chamber 11.
[0035] Furthermore, in this embodiment, it is also set that multiple columnar bodies 14 are all in contact with the heating wire partition 20, thereby ensuring timely heat transfer from the heating wire 30 to the multiple columnar bodies 14, which plays an important role in improving the heat transfer efficiency of the multiple columnar bodies 14.
[0036] It should also be pointed out that at this time, between the multiple columnar bodies 14 and the Laval nozzle 13, the surface of the reaction chamber 11 is covered with a plurality of receiving holes 15, and iridium catalysts are filled in the plurality of receiving holes 15; the plurality of receiving holes 15 can be directly formed by processing on the surface of the reaction chamber 11, as long as it is ensured that the plurality of receiving holes 15 are evenly distributed on the surface of the reaction chamber 11.
[0037] However, to ensure that the catalytic reaction proceeds more fully and efficiently, as Figure 2 and Figure 3 shown, in this embodiment, between the multiple columnar bodies 14 and the Laval nozzle 13, a porous plate 16 is provided in the reaction chamber 11. The porous plate 16 is in the shape of a rectangular plate, which separates the area where the multiple columnar bodies 14 are located from the area where the Laval nozzle 13 is located; but since at this time the plurality of receiving holes 15 are all provided on the porous plate 16, the area where the multiple columnar bodies 14 are located and the Laval nozzle 13 can be communicated by the plurality of receiving holes 15.
[0038] Moreover, as Figure 2 and Figure 3 shown, at this time the receiving holes 15 include first receiving holes 151 and second receiving holes 152; the plurality of first receiving holes 151 are straight through holes arranged horizontally, which penetrate the left and right sides of the porous plate 16, so that the plurality of first receiving holes 151 can communicate the area where the multiple columnar bodies 14 are located with the Laval nozzle 13; while the plurality of second receiving holes 152 are straight through holes arranged vertically. At this time, the plurality of second receiving holes 152 all face the heating wire partition 20 and penetrate the porous plate 16 from top to bottom, thereby realizing the communication between the plurality of second receiving holes 152 and the plurality of first receiving holes 151.
[0039] Since the first receiving hole 151 and the second receiving hole 152 are both filled with iridium catalyst at this time, no matter in which direction the propellant flows in the porous plate 16, it can make full contact with the iridium catalyst, thus ensuring the efficient and sufficient progress of the catalytic reaction.
[0040] Regarding the heating wire partition 20, as Figure 2 shown, at this time, the material of the heating wire partition 20 is silicon, the appearance size is 0.2mm * 15mm * 20mm, and the heating wire partition 20 is provided with a partition through hole 21. The partition through hole 21 can be made by etching process. In this embodiment, the partition through hole 21 is a round hole with a diameter of 1.6mm.
[0041] When installing the heating wire partition 20, the heating wire partition 20 and the thruster base 10 can be connected by bonding process, so that the heating wire partition 20 can cover the reaction chamber 11; wherein, at this time, the partition through hole 21 is opposite to the gas inlet area 12, so that the partition through hole 21 is in communication with the reaction chamber 11.
[0042] Regarding the heating wire 30, as Figure 2 shown, at this time, the material of the heating wire 30 is Pt (platinum), the thickness is 100um, and it can be connected to the thruster base 10 and the thruster end cover 40 by bonding connection, so that the heating wire 30 is arranged between the heating wire partition 20 and the thruster end cover 40.
[0043] Regarding the thruster end cover 40, as Figure 2 shown, at this time, the material of the thruster end cover 40 is silicon, the appearance size is 0.8mm * 15mm * 20mm, and the thruster end cover 40 is provided with an end cover through hole 41. The end cover through hole 41 can be made by etching process. In this embodiment, the end cover through hole 41 is a round hole with a diameter of 1.6mm.
[0044] When installing the thruster end cover 40, the heating wire partition 20 and the thruster end cover 40 can be connected by bonding process, so that the heating wire 30 can be stably installed between the heating wire partition 20 and the thruster end cover 40; wherein, at this time, the end cover through hole 41 is opposite to the partition through hole 21, so that the end cover through hole 41 is in communication with the partition through hole 21.
[0045] When applying the above single-component micro-thruster, the propellant flows through the end cover through hole 41 and the partition through hole 21 in sequence and then enters the gas inlet area 12 of the reaction chamber 11. Then the propellant will pass through the multi-columnar bodies 14 distributed in an array and undergo a catalytic decomposition reaction in the porous plate 16 filled with iridium catalyst, and the reaction products will be ejected from the Laval nozzle 13.
[0046] In summary, the present utility model has at least the following beneficial effects:
[0047] 1. For the front half of the reaction chamber 11 of the single-component micro-thruster, columnar bodies 14 are arranged in an array to improve the heat transfer efficiency, that is, to increase the temperature of the gas reaching the chamber. The chamber is designed to be porous to improve the catalytic decomposition efficiency.
[0048] 2. Nitrous oxide is selected as the propellant to achieve self-sustaining decomposition of nitrous oxide at the microscale, utilizing the chemical energy of the gas, greatly enhancing the performance of the thruster and reducing the power consumption of the thruster.
[0049] The above are the preferred embodiments of the present utility model. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present utility model, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present utility model.
Claims
1. A single - component micro - thruster based on MEMS technology, characterized in that the single - component micro - thruster is a thruster using nitrous oxide as a propellant, and the single - component micro - thruster includes a thruster base, a heating wire partition, a heating wire, and a thruster end - cap; one surface of the thruster base is provided with a reaction chamber, and the reaction chamber is provided with a gas inlet region and a Laval nozzle that are in communication with each other; the reaction chamber is provided with multiple columnar bodies at a position adjacent to the gas inlet region, and the multiple columnar bodies are arranged separately from each other; between the multiple columnar bodies and the Laval nozzle, the surface of the reaction chamber is covered with multiple receiving holes, and all the receiving holes are filled with iridium catalysts; the heating wire partition covers the reaction chamber, and the heating wire partition is provided with partition through - holes, and the partition through - holes are in communication with the reaction chamber; the heating wire is arranged between the heating wire partition and the thruster end - cap; the thruster end - cap is provided with end - cap through - holes, and the end - cap through - holes are in communication with the partition through - holes.
2. The single - component micro - thruster according to claim 1, characterized in that in the direction from the gas inlet region to the Laval nozzle, the width dimension of the gas inlet region increases.
3. The single - component micro - thruster according to claim 1, characterized in that all the multiple columnar bodies are in contact with the heating wire partition.
4. The single - component micro - thruster according to claim 1, characterized in that all the multiple columnar bodies are cylindrical.
5. The single - component micro - thruster according to claim 1, characterized in that the multiple columnar bodies are arranged in a staggered array.
6. The single - component micro - thruster according to claim 1, characterized in that between the multiple columnar bodies and the Laval nozzle, the reaction chamber is provided with a perforated plate, and all the multiple receiving holes are arranged on the perforated plate, and the region where the multiple columnar bodies are located is in communication with the Laval nozzle through the multiple receiving holes.
7. The single - component micro - thruster according to claim 6, characterized in that the receiving holes include first receiving holes and second receiving holes; the multiple first receiving holes communicate the region where the multiple columnar bodies are located with the Laval nozzle; the multiple second receiving holes are in communication with the multiple first receiving holes, and all the multiple second receiving holes face the heating wire partition.
8. The single - component micro - thruster according to claim 1, characterized in that the materials of the thruster base, the heating wire partition, and the thruster end - cap are all silicon.
9. The single - component micro - thruster according to claim 1, characterized in that the material of the heating wire is Pt.