Anode gas distributor and Hall thruster and space equipment including the same

Abstract

The present invention relates to an anode gas distributor, a Hall thruster including the same, and a space device. The anode gas distributor includes a buffer cavity, and the buffer cavity includes a top buffer cavity. The top of the top buffer cavity has an annular tapered surface structure. The present invention effectively improves the anti-sputtering and anti-bombardment capabilities of the anode, effectively alleviates the problem of uneven gas emission caused by ion backflow coating, and the tapered anode effectively improves the electric field and / or improves the discharge capacity of the Hall thruster.

Description

Technical Field

[0001] The present invention relates to the technical field of space propulsion; specifically, the present invention relates to an anode gas distributor, a Hall thruster including the same, and a space device. Background Art

[0002] The Hall thruster is a space electric propulsion device, which is widely used in the field of space propulsion and is also one of the preferred propulsion devices for future space vehicles. For example, its typical application scenarios include, but are not limited to, satellite orbit maintenance and attitude control.

[0003] Figure 1 The working principle of the Hall thruster is shown. As shown in the figure, inside the thruster, there is a pair of mutually perpendicular electric field F1 and magnetic field F2. The electric field is along the axial direction, and the magnetic field is along the radial direction. The cathode A is an electron source that maintains stable discharge. The electrons generated by it form an electron beam that moves in a circular motion under the action of the Lorentz force of the radial magnetic field. The propellant gas enters the annular discharge chamber through the anode gas distributor B, and the electrons collide violently with the propellant and ionize the propellant. Under the action of the electromagnetic field, the ions inside the thruster generate an axial acceleration and finally spray out at a high speed to form a reaction thrust.

[0004] The anode gas distributor is an important component of the Hall thruster. Among them, the anode is responsible for applying a high electric potential to accelerate electrons and receiving electrons to form an important function of the discharge circuit, while the gas distributor is used to uniformly distribute the working medium entering the discharge channel of the thruster. Generally speaking, the anode and the gas distributor of the Hall thruster are integrated. Summary of the Invention

[0005] In view of this, the present invention provides an anode gas distributor, a Hall thruster including the same, and a space device, thereby solving or at least alleviating one or more of the above problems and other problems existing in the prior art.

[0006] To achieve the foregoing object, according to a first aspect of the present invention, there is provided an anode gas distributor, wherein the anode gas distributor includes a buffer chamber, the buffer chamber includes a top buffer chamber, and the top of the top buffer chamber has an annular tapered surface structure.

[0007] Optionally, in the anode gas distributor as described above, the end face material of the top buffer chamber is tungsten.

[0008] Optionally, in the anode gas distributor as described above, the overall material of the top buffer chamber is tungsten, and the material of other parts of the anode gas distributor is tantalum.

[0009] Optionally, in the anode gas distributor as described above, the annular conical surface structure is a double-annular conical surface structure or a multi-annular conical surface structure, and multiple groups of air outlet holes are provided in the upper grooves between the conical surface structures of the double-annular conical surface structure or the multi-annular conical surface structure.

[0010] Optionally, in the anode gas distributor as described above, the anode gas distributor further includes a bottom plate seat, an air inlet column, and a fixing stud. The bottom plate seat is circular and has a primary air inlet hole for connecting to the air inlet column and delivering gas to the buffer chamber. One side of the bottom plate seat is installed in the buffer chamber, and the air inlet column and the fixing stud are fixed to the other side of the bottom plate seat.

[0011] Optionally, in the anode gas distributor as described above, the anode gas distributor includes two of the air inlet columns and two of the fixing studs, and the air inlet column and the fixing stud have the same length.

[0012] Optionally, in the anode gas distributor as described above, the buffer chamber further includes one or more intermediate buffer chambers between the top buffer chamber and the bottom plate seat. The top buffer chamber and the intermediate buffer chambers each have a circumferential lower groove, and the outer diameter and inner diameter of the lower groove of the top buffer chamber and the lower groove of the intermediate buffer chambers are the same.

[0013] Optionally, in the anode gas distributor as described above, the air outlet holes of the intermediate buffer chamber are arranged on the top plane, the air outlet holes of the top buffer chamber are evenly arranged on the circumferential side, and one of the air outlet holes of the intermediate buffer chamber is aligned with the primary air inlet hole on the bottom plate seat.

[0014] To achieve the foregoing purpose, according to a second aspect of the present invention, a Hall thruster is provided, wherein the anode gas distributor of the Hall thruster is the anode gas distributor as described in any one of the foregoing first aspects.

[0015] To achieve the foregoing purpose, according to a third aspect of the present invention, a space device is provided, wherein the anode gas distributor of the Hall thruster of the space device is the anode gas distributor as described in any one of the foregoing first aspects.

[0016] The present invention is directed to an anode gas distributor and a Hall thruster and a space device including the same, effectively improving the anti-sputtering and anti-bombardment ability of the anode, effectively alleviating the problem of uneven gas emission caused by ion backflow coating, and the conical anode effectively improving the electric field and / or improving the discharge ability of the Hall thruster. Description of the Drawings

[0017] With reference to the accompanying drawings, the disclosure of the present invention will become more apparent. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of the present invention. In the figures:

[0018] Figure 1 is a schematic diagram of a prior art Hall thruster;

[0019] Figure 2 is a schematic perspective view of an embodiment of the anode gas distributor of the Hall thruster of the present invention;

[0020] Figure 3 is Figure 2 a schematic side cross-sectional view of the anode gas distributor in

[0021] Figure 4 is a schematic perspective view of another embodiment of the anode gas distributor of the Hall thruster of the present invention;

[0022] Figure 5 is Figure 4 a schematic side cross-sectional view of the anode gas distributor in

[0023] Figure 6 is Figure 2 and Figure 4 a schematic perspective view of the intermediate buffer cavity of the anode gas distributor in

[0024] Figure 7 and Figure 2 is Figure 4 a schematic perspective view of the bottom plate seat, intake column and fixing stud of the anode gas distributor in

[0025] Reference numerals: A - cathode; B - anode gas distributor; 1 - bottom plate seat; 2 - intake column; 3 - fixing stud; 4 - intermediate buffer cavity; 5 - top buffer cavity; 6 - intermediate buffer cavity outlet hole; 7 - top buffer cavity outlet hole; 8 - primary intake hole; 9 - tapered surface structure; 10 - lower groove of the intermediate buffer cavity; 11 - lower groove of the top buffer cavity; 12 - upper groove of the top buffer cavity; 13 - upper groove outlet hole. Detailed Embodiments

[0026] With reference to the accompanying drawings and specific embodiments, the structural composition, characteristics and advantages of the anode gas distributor according to the present invention, the Hall thruster including the same, and the space equipment will be described by way of example below. However, all descriptions should not be used to form any limitation to the present invention.

[0027] In addition, for any single technical feature described or implied in the embodiments mentioned in this document, or any single technical feature shown or implied in the respective drawings, the present invention still allows for any combination or deletion between these technical features (or their equivalents) without any technical obstacles. Therefore, it should be considered that these additional embodiments according to the present invention are also within the scope of the description herein.

[0028] It should also be noted that in the description of the present invention, the terms indicating directions or positional relationships such as "upper", "lower", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings. This is only for convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0029] Figure 2 is a schematic perspective view of an embodiment of the anode gas distributor of the Hall thruster of the present invention; Figure 3 is Figure 2 a schematic side cross-sectional view of the anode gas distributor in. As can be seen from the figure, the anode gas distributor includes a bottom plate seat 1, an intake column 2, a fixing stud 3, an intermediate buffer cavity 4, a top buffer cavity 5, an intermediate buffer cavity air outlet 6, and a top buffer cavity air outlet 7.

[0030] As shown in the figure, the anode gas distributor includes a buffer cavity. In this example, the buffer cavity includes a top buffer cavity 5 and an intermediate buffer cavity 4. In the illustrated example, there is only one intermediate buffer cavity 4; in other embodiments, more than one intermediate buffer cavity 4 can be provided, or the intermediate buffer cavity can be not provided.

[0031] As Figure 2 and Figure 3 shown in, the top end of the top buffer cavity 5 can have an annular tapered surface structure 9. In this embodiment, the annular tapered surface structure 9 is a single annular tapered surface structure. The single-tip top buffer cavity 5 is processed with wire electrical discharge machining to produce a single tip.

[0032] The top end of the top buffer cavity 5 is the anode end face, and its annular tapered surface structure can, to a certain extent, shorten the distance from the anode gas distributor to the discharge channel outlet, thereby effectively increasing the local electric field strength of the Hall thruster, increasing the electron energy on the path, making the discharge simpler and faster, and increasing the outgoing ion velocity on the path, thereby increasing the ionization rate, thrust, and specific impulse.

[0033] Furthermore, the material of the top surface of the top buffer cavity can be tungsten. Alternatively, in an optional embodiment, the overall material of the top buffer cavity can be tungsten. At the same time, the material of other parts of the anode gas distributor can be tantalum. Specifically, the materials of the bottom plate seat 1, the intake column 2, the fixing stud 3, and the intermediate buffer cavity 4 can all be tantalum.

[0034] Compared with the conventional stainless steel or tantalum material anode gas distributor, the tungsten material anode end face has stronger anti-sputtering and bombardment resistance, which can effectively slow down the bombardment sputtering at the tip part, especially can extend the life of the tip part with high field strength and more vulnerable to bombardment; tungsten has strong high-temperature resistance, can withstand large power deposition generated by continuous bombardment heating of the electron current, and has a higher working temperature.

[0035] In addition to the above top buffer cavity 5, the buffer cavity can also include one or more intermediate buffer cavities located between the top buffer cavity 5 and the bottom plate seat 1. Such as Figure 2 and 3 The embodiment of

[0036] Such as Figure 3 As shown in

[0037] In the illustrated example, the air outlet holes 6 of the intermediate buffer cavity 4 are arranged on the top plane. The air outlet holes 7 of the top buffer cavity 5 are uniformly arranged on the circumferential side. The working gas from the intermediate buffer cavity 4 directly enters the top buffer cavity 5 through the air outlet holes 6, and then discharges inwards and outwards along the circumferential side. The uniform circumferential side arrangement of the air outlet holes 7 of the top buffer cavity 5 can effectively prevent the deposition coating of the reflux ions on the air outlet holes, ensure the consistency of the air outlet hole diameter, and ensure the uniformity of the working medium gas.

[0038] From Figure 3It can be seen more clearly that the air outlet holes 7 of the top buffer cavity are placed on the side of the anode gas distributor. In this way, the ions flowing back to the anode will first deposit on the two side surfaces of the tip of the top buffer cavity 5, and it is difficult to move to the side of the top buffer cavity 5, ensuring that the side air outlet holes will not be deposited with ions, ensuring the consistency of the air outlet diameter, ensuring the uniformity and stability of the gas outlet volume during the operation of the thruster, and the ion deposition film tends to be distributed on the surface near the tip and is difficult to directly deposit on the tip, ensuring that an electric field can be stably generated at the tip, preventing the occurrence of the anode surface insulation phenomenon caused by the deposition film, ensuring the stable operation of the thruster anode, and further ensuring the stable progress of discharge ionization.

[0039] From Figure 3 it can also be seen that both the middle buffer cavity 4 and the top buffer cavity 5 are provided with lower grooves, namely the lower groove 10 of the middle buffer cavity 4 and the lower groove 11 of the top buffer cavity 5, and the outer diameters and inner diameters of the lower grooves 10 and 11 are the same.

[0040] The top buffer cavity 5 extends a section (or two sections, see Figure 4 and Figure 5 ) of protruding tips on a structure similar to that of the middle buffer cavity 4. The cone angle of one section (or two sections) of the tips can be, for example but not limited to, 60°, and the lower groove 11 is also arranged. A plurality of completely penetrating air outlet holes 7 of the top buffer cavity are evenly distributed at a certain angular interval along the circumferences on both sides inside the lower groove 11 of the top buffer cavity 5. Each pair of air outlet holes 7 of the top buffer cavity on both sides is coaxial. The axis connection lines of the paired air outlet holes 7 of the top buffer cavity 5 inside the lower groove 11 all pass through the above-mentioned coaxial axis.

[0041] In an alternative embodiment, the axis connection lines of all pairs of air outlet holes 7 of the top buffer cavity 5 inside the lower groove 11 all pass through the centers of all the air outlet holes 6 on the upper surface of the middle buffer cavity 4.

[0042] From Figure 2 and Figure 3 it can be seen that the anode gas distributor may further include a bottom plate seat 1, an air inlet column 2, and a fixing stud 3.

[0043] In the illustrated embodiment, the bottom plate seat 1 can be circular, and the bottom plate seat 1 can have primary air inlet holes 8, a total of two, arranged at the diameter center ring of the center of its inner and outer rings, see Figure 7 . The primary air inlet holes 8 are used to connect with the air inlet column 2 and convey gas to the buffer cavity 5. The primary air inlet holes 8 on the bottom plate seat 1 are coaxial with a certain air outlet hole 6 on the upper surface of the middle buffer cavity 4, and thus are aligned and communicated.

[0044] One side of the base plate seat 1 is installed in the buffer cavity. For example, in the illustrated embodiment, it is installed in the middle buffer cavity 4 and the top buffer cavity 5. In an embodiment without a middle buffer cavity, the base plate seat 1 can also be directly installed in the top buffer cavity 5. In an alternative embodiment, the middle buffer cavity 4 and the base plate seat 1 can be precisely connected by electron beam welding; furthermore, the top buffer cavity 5 and the middle buffer cavity 4 can also be precisely connected by electron beam welding. The outer diameters of the base plate seat 1, the middle buffer cavity 4, and the top buffer cavity 5 are the same.

[0045] On the other side of the base plate seat 1, an intake column 2 and a fixing stud 3 are fixedly installed.

[0046] Corresponding to the number of primary intake holes 8, the anode gas distributor includes two intake columns 2. The intake column 2 is a hollow tube and can be precisely fixed to the base plate seat 1 by means such as but not limited to electron beam welding. There are two fixing studs 3 in total. The tail of it can have threads, be integrally machined with the base plate seat 1, and then undergo threading treatment.

[0047] In this way, there are a total of four intake columns 2 and fixing studs 3, which are evenly distributed along the circumferential direction at an angular interval of 90 degrees on one side of the central ring of the base plate seat 1. In an alternative embodiment, other numbers of intake columns and fixing bolts can be selected. The lengths of the intake column 2 and the fixing stud 3 can be the same.

[0048] In this way, this embodiment provides a double-tube intake double-layer intake buffer cavity (middle buffer cavity 4, top buffer cavity 5) and two intake columns 2, which can effectively buffer and fully homogenize the working medium gas. Moreover, a plurality of top buffer cavity outlet holes 7 are arranged oppositely on the side, and the gas enters radially in parallel on both sides, which has better uniformity and a larger intake volume compared with the traditional axial intake, ensuring the uniformity of the plasma generated after the ionization of the working medium gas in the discharge cavity.

[0049] Figure 4 It is a schematic perspective view of another embodiment of the anode gas distributor of the Hall thruster of the present invention. Figure 5 is Figure 4 a schematic side sectional view of the anode gas distributor in Figure 4 and Figure 5 The technical solutions of the embodiments in Figure 2 and Figure 3 are basically completely the same as the technical solutions of the embodiments in

[0050] In this embodiment, the annular tapered surface structure 9 is a double-annular tapered surface structure. In an alternative embodiment, it is conceivable to use a multi-annular tapered surface structure, such as a triple-annular, quadruple-annular, or more. The double-tip groove-shaped top buffer cavity 5 can be machined with a double tip using electrical discharge machining. There is an upper groove 12 between the double-annular tapered surface and the multi-annular tapered surface.

[0051] Similarly, the tapered surface structure at the upper end of the top buffer cavity 5 can, to a certain extent, shorten the distance from the anode gas distributor to the discharge channel outlet, thereby achieving local electric field enhancement, enabling electrons flowing towards this tip to obtain higher energy when traveling the same path, effectively reducing the discharge difficulty, and improving the ionization effect of the thruster, especially for small-sized permanent magnet Hall thrusters. At the same time, it can increase the ion emission velocity, thereby enhancing the thrust and specific impulse of the thruster. The anode gas distributor structure with upper and lower grooves in the double-tip or multi-tip can effectively avoid the radial magnetic field constraint area of the anode, preventing serious bombardment of the anode by electrons caused by the intersection of the anode and magnetic field lines and avoiding serious electron loss.

[0052] To ensure sufficient density of the working medium gas in the upper groove area at the tip center, Figure 4 and Figure 5 in the illustrated embodiment, based on the original side gas outlet, multiple groups of air holes 13 are added in the upper groove 12, and these air holes 13 lead from the lower groove 11 of the top buffer cavity 5 to the upper groove 12. The axis connection lines of all multiple pairs of top buffer cavity air holes 7 in the lower groove 11 of the top buffer cavity 5 all pass through the centers of the multiple groups of air holes 13 in the upper groove 12, as shown in Figure 4 and Figure 5 shown.

[0053] Figure 6 is Figure 2 and Figure 4 a schematic perspective view of the intermediate buffer cavity of the anode gas distributor in. This figure shows the top surface of the intermediate buffer cavity 4, rather than showing the lower groove 10 of the intermediate buffer cavity 4. Multiple intermediate buffer cavity air holes 6 are evenly distributed along its top surface, and the distances from them to the annular outer and inner peripheries of the intermediate buffer cavity 4 are the same.

[0054] Figure 7 is Figure 2 and Figure 4 a schematic perspective view of the bottom plate seat, intake column, and fixing studs of the anode gas distributor in. This figure shows the annular bottom plate seat 1 and two primary intake holes 8 on the bottom plate seat 1. These two primary intake holes 8 are symmetrically distributed and respectively correspond to the positions of the intake columns 2. Two fixing studs 3 and two intake columns 2 are evenly distributed on the circumference of the bottom plate seat 1, with an angular separation of 90 degrees between each pair. For a more detailed description of the bottom plate seat 1, intake column 2, and fixing studs 3, more details described above can be referred to.

[0055] Another aspect of the present invention also provides a Hall thruster, wherein the anode gas distributor of the Hall thruster is the anode gas distributor described in any one of the foregoing embodiments. Other aspects of the present invention also provide a space device, wherein the anode gas distributor of the Hall thruster of the space device is the anode gas distributor described in any one of the foregoing embodiments. For example, these space devices can be artificial satellites, space stations, etc. The Hall thruster and the space device arranged in this way have the respective characteristics of the anode gas distributor in the foregoing embodiments, and thus also have their corresponding advantages.

[0056] The following describes the specific working process in combination with the Hall thruster in the space device as follows: (1) The working medium gas first enters the intermediate buffer chamber 4 from the intake column 2 through the two primary intake holes 8 on the bottom plate seat 1, and then enters the top buffer chamber 5 from the intermediate buffer chamber outlet hole 6 in the lower groove 10 of the intermediate buffer chamber 4, and finally enters the discharge chamber radially through the circumferentially arranged top buffer chamber outlet holes 7 on both sides of the top buffer chamber 5, completing the uniform distribution of the working medium gas. (2) After the thrust magnetic field is constructed and the anode is ignited, the space primary electrons and the external cathode electrons are accelerated by the anode and start to move towards the anode. The conical anode will enhance the local electric field, making the electrons have higher energy. Subsequently, the accelerated electrons enter the radial magnetic field confinement region to perform circumferential Hall drift and ionize the working medium gas from the axial direction. After losing energy through ionization, the electrons migrate towards the anode, bombard the anode to form an electron current, and transfer the remaining energy to the anode to form power deposition and heat the anode. Some of the reflux ions have a chance to deposit at both ends of the anode tip and coat the inclined surface, while the side outlet holes are not affected by the deposited coating. (3) During the working process, the electrons will continuously bombard the anode tip and form power deposition. Due to the anti-bombardment sputtering and high-temperature resistance characteristics of the tungsten material itself, the bombardment sputtering at the tip is effectively slowed down, effectively extending the life of the tip, and its high-temperature resistance characteristics enable it to work normally at a higher temperature.

[0057] The above advantages and optimization points ensure the originality and uniqueness of the present invention, can effectively improve the anode power load of the Hall thruster, effectively avoid the uneven gas outlet caused by the coating of the outlet hole by the reflux ions, resulting in uneven plasma density in the channel. The tip effectively enhances the local field strength, improves the discharge ignition ability, and the tungsten tip effectively slows down the tip passivation caused by electron bombardment sputtering, extending the life of the anode gas distributor.

[0058] The technical scope of the present invention is not limited to the content described in the above description. Those skilled in the art can make various deformations and modifications to the above embodiments without departing from the technical idea of the present invention, and these deformations and modifications should all fall within the scope of the present invention.

Claims

1. An anode gas distributor, characterized in that, The anode gas distributor includes a buffer chamber, and the buffer chamber includes a top buffer chamber. Among them, the top of the top buffer chamber has an annular tapered surface structure, and the tapered surface structure is a protruding tip extending from the top of the top buffer chamber. And the top of the top buffer chamber is the anode end face. The annular tapered surface structure is a double-annular tapered surface structure or a multi-annular tapered surface structure, and multiple groups of air outlet holes are arranged in the upper grooves between the tapered surface structures of the double-annular tapered surface structure or the multi-annular tapered surface structure.

2. The anode gas distributor according to claim 1, wherein, The end face material of the top buffer chamber is tungsten.

3. The anode gas distributor according to claim 2, wherein, The overall material of the top buffer chamber is tungsten, and the materials of the other parts of the anode gas distributor are tantalum.

4. The anode gas distributor according to claim 1, wherein, The anode gas distributor further includes a bottom plate seat, an air inlet column, and a fixing stud. The bottom plate seat is circular and has a primary air inlet hole for connecting with the air inlet column and delivering gas to the buffer chamber. One side of the bottom plate seat is installed on the buffer chamber, and the air inlet column and the fixing stud are fixed on the other side of the bottom plate seat.

5. The anode gas distributor according to claim 4, wherein The anode gas distributor includes two of the air inlet columns and two of the fixing studs, and the lengths of the air inlet column and the fixing stud are the same.

6. The anode gas distributor according to claim 4, wherein, The buffer chamber further includes one or more intermediate buffer chambers located between the top buffer chamber and the bottom plate seat. The top buffer chamber and the intermediate buffer chambers all have circumferential lower grooves, and the outer diameters and inner diameters of the lower grooves of the top buffer chamber and the lower grooves of the intermediate buffer chambers are the same.

7. The anode gas distributor according to claim 6, wherein, The air outlet holes of the intermediate buffer chamber are arranged on the top plane, the air outlet holes of the top buffer chamber are evenly arranged on the circumferential side, and one of the air outlet holes of the intermediate buffer chamber is aligned with the primary air inlet hole on the bottom plate seat.

8. A Hall thruster, characterized in that, The anode gas distributor of the Hall thruster is the anode gas distributor according to any one of the preceding claims 1 to 7.

9. A space device, characterized in that, The anode gas distributor of the Hall thruster of the space equipment is the anode gas distributor according to any one of the preceding claims 1 to 7.

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