Focusing electrode structure of field emission thruster with plume

Abstract

The utility model relates to the technical field of focusing electrode arrays, and particularly discloses a field emission thruster focusing electrode structure with a plume, which comprises an insulating bracket, an extraction electrode, a focusing electrode and an acceleration electrode, the insulating bracket is provided with a first connecting sheet, a second connecting sheet, a third connecting sheet and an assembling hole; the extraction electrode is configured to be fixedly connected with the first connecting sheet and is located in the assembly hole; the focusing electrode is fixedly connected with the second connecting sheet and is positioned in the assembly hole; the accelerating pole is fixedly connected with the third connecting piece and is positioned in the assembling hole; the central axes of the extraction electrode, the focusing electrode and the acceleration electrode coincide; the focusing electrode is positioned between the extraction electrode and the acceleration electrode; according to the focusing electrode structure of the field emission thruster with the charged plume, the focusing effect can be enhanced, the adverse effect caused by the plume is reduced, and the comprehensive performance of the thruster is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of focusing electrode arrays, in particular to a focusing electrode structure for a charged plume of a field emission thruster. Background Art

[0002] In the pure ion emission mode of the field emission thruster, the thruster has higher efficiency and specific impulse, but it will produce charged plumes, causing problems such as charging of the spacecraft surface, charge exchange between the plume and the spacecraft surface, and electromagnetic interference. In addition, since the particles have higher energy during pure ion emission, sputtering corrosion will occur on the internal components of the thruster, resulting in reduced reliability of the thruster and shortened service life.

[0003] To this end, a focusing electrode array is designed to optimize the plume. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a focusing electrode structure for a charged plume of a field emission thruster, which can enhance the focusing effect, reduce the adverse effects brought by the plume, and improve the comprehensive performance of the thruster.

[0005] In order to solve the above problems, the utility model adopts the following technical solutions:

[0006] A focusing electrode structure for a charged plume of a field emission thruster comprises an insulating support, an extraction electrode, a focusing electrode and an accelerating electrode.

[0007] The insulating bracket has a first connecting piece, a second connecting piece, a third connecting piece and an assembly hole.

[0008] The extraction electrode is configured to be fixedly connected to the first connecting piece and is located in the assembly hole.

[0009] The focusing electrode is configured to be fixedly connected to the second connecting piece and is located in the assembly hole.

[0010] The accelerating electrode is configured to be fixedly connected to the third connecting piece and is located in the assembly hole.

[0011] The central axes of the extraction pole, the focusing pole and the accelerating pole coincide with each other.

[0012] The focusing pole is located between the extraction pole and the accelerating pole.

[0013] In the focusing electrode structure of the charged plume of a field emission thruster provided by at least one embodiment of the present disclosure, the first connecting piece, the second connecting piece and the third connecting piece are staggered.

[0014] In the focusing electrode structure of the charged plume of a field emission thruster provided in at least one embodiment of the present disclosure, the central axes of the extraction electrode, the focusing electrode and the accelerating electrode all coincide with the central axis of the assembly hole.

[0015] In the focusing electrode structure for charged plume of a field emission thruster provided by at least one embodiment of the present disclosure, one end of the first connecting piece is fixedly connected to the wall surface of the insulating bracket.

[0016] One end of the second connecting piece and one end of the third connecting piece are both fixedly connected to the hole wall of the assembly hole.

[0017] In the focusing electrode structure of the charged plume of a field emission thruster provided by at least one embodiment of the present disclosure, a first connecting portion is provided on the extraction electrode, and the first connecting portion is configured to be bolted to the first connecting piece.

[0018] A second connection portion is disposed on the focusing electrode, and the second connection portion is configured to be bolted to the second connection piece.

[0019] The accelerating electrode is provided with a third connecting portion, and the third connecting portion is configured to be bolted to the third connecting piece.

[0020] In the focusing electrode structure of the charged plume of a field emission thruster provided by at least one embodiment of the present disclosure, a plurality of the first connecting plates, the second connecting plates and the third connecting plates are configured, and the plurality of the first connecting plates, the second connecting plates and the third connecting plates are distributed in a ring array.

[0021] In the focusing electrode structure of the charged plume of a field emission thruster provided by at least one embodiment of the present disclosure, the extraction electrode and the first connecting portion are integrally arranged.

[0022] The focusing electrode and the second connecting portion are integrally arranged.

[0023] The accelerating electrode and the third connecting portion are integrally arranged.

[0024] The beneficial effects of the utility model are:

[0025] The focusing electrode array obtained only by simple mechanical processing can achieve an enhanced focusing effect, reduce the adverse effects of the plume, improve the overall performance of the thruster, and reduce the cost.

[0026] Compared with the existing technology that leads to reduced comprehensive performance of the thruster or damage to the mechanical structure and reduced thruster life, the use of a focusing electrode structure to solve the plume charging problem and reasonably arrange the electrode distribution can effectively constrain the plume and greatly reduce the plume divergence angle, thereby reducing the sputtering corrosion of the thruster components by the plume, increasing the thrust, and improving the reliability and life of the thruster.

[0027] By optimizing the plume through the focusing structure, the ions can be ejected in a direction parallel to the thruster centerline, reducing the plume divergence angle, increasing the degree of plume aggregation near the axis, making the thrust vector more accurate, and reducing thruster losses to a certain extent, improving thrust, specific impulse and efficiency. Therefore, using this focusing structure to optimize the plume can improve the overall performance of the thruster and has greater application value. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a stereoscopic diagram of a focusing electrode structure of a charged plume of a field emission thruster according to the utility model.

[0030] Figure 2 A three-dimensional diagram of an insulating bracket.

[0031] Figure 3 A stereogram for extracting the pole.

[0032] Figure 4 This is a stereogram of the focusing pole.

[0033] Figure 5 This is a three-dimensional diagram of the accelerating electrode.

[0034] Figure 6 Schematic diagram of the arrangement of plume angle measurement components.

[0035] Figure 7 Schematic diagram of current density of the needle-plate structure group within different plume angle ranges.

[0036] Figure 8 Schematic diagram of current density of the focusing structure group within different plume angle ranges.

[0037] In the figure:

[0038] 10. Insulating bracket; 11. First connecting piece; 12. Second connecting piece; 13. Third connecting piece; 14. Assembly hole;

[0039] 20. extraction pole; 21. first connection portion;

[0040] 30. focusing electrode; 31. second connecting portion;

[0041] 40. accelerating electrode; 41. third connecting portion;

[0042] 50. Circular collecting plate;

[0043] 60. Three-axis displacement platform;

[0044] 70. High voltage power supply module;

[0045] 80. Oscilloscope current collection module;

[0046] 90. Emitter. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments will be described clearly and completely below in conjunction with the drawings in the embodiments. Obviously, the described embodiments are only a part of the embodiments, rather than all the embodiments.

[0048] Example

[0049] like Figures 1 to 5 As shown, a focusing electrode structure of a field emission thruster charged plume includes an insulating support 10, an extraction electrode 20, a focusing electrode 30 and an accelerating electrode 40.

[0050] Specifically, the insulating bracket 10 has a first connecting piece 11 , a second connecting piece 12 , a third connecting piece 13 and an assembly hole 14 .

[0051] Further, the extraction electrode 20 is configured to be fixedly connected to the first connecting piece 11, and the extraction electrode 20 is located in the assembly hole 14. The focusing electrode 30 is configured to be fixedly connected to the second connecting piece 12, and the focusing electrode 30 is located in the assembly hole 14. The accelerating electrode 40 is configured to be fixedly connected to the third connecting piece 13, and the accelerating electrode 40 is located in the assembly hole 14.

[0052] Furthermore, the central axes of the extraction electrode 20 , the focusing electrode 30 and the accelerating electrode 40 coincide with each other. The focusing electrode 30 is located between the extraction electrode 20 and the accelerating electrode 40 .

[0053] Furthermore, the central axes of the extraction electrode 20 , the focusing electrode 30 and the accelerating electrode 40 all coincide with the central axis of the assembly hole 14 .

[0054] In this embodiment, the extraction electrode, the focusing electrode and the accelerating electrode are machined, the electrode material is stainless steel, and the insulating bracket 10 is 3D printed, the material of the insulating bracket 10 is Teflon, and the processing accuracy is 0.1 mm.

[0055] In this embodiment, the first connecting piece 11 , the second connecting piece 12 and the third connecting piece 13 are staggered.

[0056] Specifically, one end of the first connecting piece 11 is fixedly connected to the wall surface of the insulating bracket 10 . One end of the second connecting piece 12 and one end of the third connecting piece 13 are both fixedly connected to the hole wall of the assembly hole 14 .

[0057] In this embodiment, a plurality of first connection parts 21 are provided on the extraction pole 20 . The plurality of first connection parts 21 are distributed in a ring array. The first connection parts 21 are configured to be bolted to the first connection sheet 11 .

[0058] Furthermore, a plurality of second connection parts 31 are provided on the focusing electrode 30 . The plurality of second connection parts 31 are distributed in a ring array. The second connection parts 31 are configured to be bolted to the second connection sheet 12 .

[0059] Furthermore, a plurality of third connection portions 41 are disposed on the accelerating electrode 40 . The plurality of third connection portions 41 are distributed in a ring array. The third connection portions 41 are configured to be bolted to the third connection sheet 13 .

[0060] In this embodiment, the extraction electrode 20 and the first connection part 21 are integrally arranged. The focusing electrode 30 and the second connection part 31 are integrally arranged. The accelerating electrode 40 and the third connection part 41 are integrally arranged. The integrated design has good integrity and stable structure.

[0061] The following is a comparative experiment between the focusing structure in the embodiment and the traditional pin-plate structure. By analyzing the falling position of the current on the circular collecting sheet, the plume divergence half angle is calculated to verify the focusing performance of the focusing structure in the embodiment. Specifically, it is divided into a focusing structure group and a pin-plate structure group.

[0062] like Figure 6-8 As shown, the extraction pole 20, the focusing pole 30 and the accelerating pole 40 are connected with external wires for power supply, and the insulating bracket 10 is fixed on the optical plate by bolts and aligned with the edge of the optical plate. The field emission thruster experimental prototype and the focusing structure are kept vertical by connecting parts and aligned by the three-axis displacement platform 60 under the emitter 90.

[0063] The emitter 90 is connected to the high voltage power module 70, and the potential of the emitter and the focusing electrode is set to be equal, that is, V emi =V f The extraction electrode and the acceleration electrode are grounded, that is, V e =V a =0V.

[0064] At the same time, the oscilloscope current collection module 80 is used to collect the current on the extraction electrode, the acceleration electrode and the circular collection plate 50, and the current ratio of each part is calculated to analyze the focusing effect.

[0065] The thrusters were stably fired at 2800V and 3000V, and data were collected to perform calculations and analyses on the plume divergence half-angle.

[0066] The calculated plume divergence half angle for the focusing structure group at 2800 V is between 10.6° and 11.6°. The calculated plume divergence half angle at 3000 V is 11.6°.

[0067] The plume divergence half-angles of the needle-plate structure group at emission voltages of 2800V and 3000V are 35.8° and 40.8° respectively.

[0068] The experimental and numerical simulation plume divergence half-angle data of the focusing structure group and the needle plate structure group are summarized in the following table:

[0069]

[0070] By comparing the plume divergence half-angle data of the two prototypes solved by experimental data, it can be seen that the focusing structure can effectively reduce the plume divergence half-angle. After optimization, the maximum divergence half-angle is only 1 / 3 of the previous one, which is about 11°.

[0071] Further analysis of the current density within different plume angle ranges of the circular collecting plate shows that the focusing structure optimizes the plume and can also cause ions to be ejected in a direction parallel to the central axis of the thruster, thereby reducing the plume divergence angle and increasing the degree of plume aggregation near the axis. This can make the thrust vector more precise and reduce thruster losses to a certain extent, thereby improving thrust, specific impulse and efficiency.

[0072] Therefore, using the focusing structure in the embodiment to optimize the plume can improve the overall performance of the thruster and has greater application value.

[0073] Although the embodiments of the present application have been shown and described above, the scope of protection of the present invention is not limited thereto, and any changes or substitutions that are not conceivable through creative work should be included in the scope of protection of the present invention; unless explicitly stated, any element, action or instruction used in this document should not be interpreted as critical or necessary.

Claims

1. A focusing electrode structure for a charged plume of a field emission thruster, characterized in that: include: An insulating bracket, comprising a first connecting piece, a second connecting piece, a third connecting piece and an assembly hole; An extraction electrode, configured to be fixedly connected to the first connecting piece and located in the assembly hole; A focusing electrode, configured to be fixedly connected to the second connecting piece and located in the assembly hole; as well as An accelerating electrode, configured to be fixedly connected to the third connecting piece and located in the assembly hole; Wherein, the central axes of the extraction pole, the focusing pole and the accelerating pole coincide with each other; The focusing pole is located between the extraction pole and the accelerating pole.

2. The focusing electrode structure of a field emission thruster charged plume according to claim 1, characterized in that: The first connecting piece, the second connecting piece and the third connecting piece are staggeredly distributed.

3. The focusing electrode structure of a field emission thruster charged plume according to claim 1, characterized in that: The central axes of the extraction pole, the focusing pole and the accelerating pole all coincide with the central axis of the assembly hole.

4. The focusing electrode structure of a field emission thruster charged plume according to claim 2, characterized in that: One end of the first connecting piece is fixedly connected to the wall surface of the insulating bracket; One end of the second connecting piece and one end of the third connecting piece are both fixedly connected to the hole wall of the assembly hole.

5. The focusing electrode structure of a field emission thruster charged plume according to claim 1, characterized in that: The extraction pole is provided with a first connection portion, and the first connection portion is configured to be bolted to the first connection piece; A second connecting portion is provided on the focusing electrode, and the second connecting portion is configured to be bolted to the second connecting piece; The accelerating electrode is provided with a third connecting portion, and the third connecting portion is configured to be bolted to the third connecting piece.

6. The focusing electrode structure of a field emission thruster charged plume according to claim 2, characterized in that: The first connecting piece, the second connecting piece and the third connecting piece are each configured in plurality, and the plurality of the first connecting pieces, the second connecting pieces and the third connecting pieces are distributed in a ring array.

7. The focusing electrode structure of a field emission thruster charged plume according to claim 5, characterized in that: The extraction electrode and the first connection portion are integrally arranged; The focusing electrode and the second connecting portion are integrally arranged; The accelerating electrode and the third connecting portion are integrally arranged.

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