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CN-122014551-A - Annular porous structure cathode for magnetic plasma power thruster

CN122014551ACN 122014551 ACN122014551 ACN 122014551ACN-122014551-A

Abstract

The invention relates to an annular porous structure cathode for a magnetic plasma power thruster, which belongs to the technical field of electric propulsion power devices of space aircrafts and comprises an inner ring emitter and an outer ring emitter, wherein the outer ring emitter is a cylinder, one end of the outer ring emitter is provided with a circular groove, the inner ring emitter is arranged in the circular groove, the inner ring emitter is provided with an inner air supply hole, an annular discharge cavity is formed between the inner ring emitter and the outer ring emitter, the annular discharge cavity and the inner air supply hole jointly form a cathode discharge channel, a plurality of outer air supply holes are arranged on the circular groove, the other end of the outer ring emitter is provided with a tail air containing cavity, and the tail air containing cavity is communicated with the inner air supply hole and the outer air supply hole. According to the invention, through the structural design of the inner ring emitter and the outer ring emitter, the effective current emission area of the cathode is increased by more than 20%, the timely export of heat is ensured, the occurrence of cathode partial burning phenomenon is reduced, and the ignition stability is improved.

Inventors

  • LI YONG
  • WU QINGYUE
  • ZHANG BO
  • WANG GE
  • ZHOU CHENG
  • KONG CHUNCAI
  • ZHANG XINWEI
  • WANG BAOJUN
  • WU PENG
  • CONG YUNTIAN
  • Han Daoman

Assignees

  • 北京控制工程研究所

Dates

Publication Date
20260512
Application Date
20260317

Claims (10)

  1. 1. The annular porous structure cathode for the magnetic plasma power thruster is characterized by comprising a cathode main body (7), wherein the cathode main body (7) comprises an inner ring emitter (2) and an outer ring emitter (1), the outer ring emitter (1) is a cylinder, one end of the outer ring emitter is provided with a circular groove, the inner ring emitter (2) is annular, the inner ring emitter (2) is arranged in the circular groove, a through hole is arranged on the circular groove, the inner through hole of the inner ring emitter (2) is connected with the through hole to form an inner air supply hole (3), an annular discharge cavity (8) is formed between the outer side surface of the inner ring emitter (2) and the side wall surface of the circular groove of the outer ring emitter (1), and the annular discharge cavity (8) and the inner air supply hole (3) jointly form a cathode discharge channel; a plurality of outer air supply holes (4) are formed in the circular groove, a tail air containing cavity (5) is formed in the other end of the outer ring emitter (1), and the tail air containing cavity (5) is communicated with the inner air supply holes (3) and the outer air supply holes (4).
  2. 2. The annular porous cathode for a magnetic plasma power thruster of claim 1, wherein the tail gas chamber (5) is internally provided with a gas damping pad (6) for damping the propellant flowing from one end of the tail gas chamber (5) and balancing the distribution of the propellant between the inner and outer gas supply holes.
  3. 3. An annular porous structured cathode for a magnetic plasma power thruster according to claim 1, characterized in that the central axes of the inner ring emitter (2) and the outer ring emitter (1) coincide.
  4. 4. An annular porous structured cathode for a magnetic plasma power thruster according to claim 1, characterized in that the depth of the annular discharge chamber (8) is 30% -45% of the total length of the cathode body (7).
  5. 5. A cathode with annular porous structure for a magnetic plasma power thruster according to claim 1, wherein the ratio of the area of the side wall surface of the inner gas supply hole (3) to the total area of the side wall surfaces of the plurality of outer gas supply holes (4) is equal to the ratio of the area of the side wall surface of the inner ring emitter (2) to the sum of the area of the side wall surface of the inner ring of the outer ring emitter (1) and the area of the side wall surface of the outer ring.
  6. 6. The annular porous cathode for a magnetic plasma power thruster of claim 1, wherein the outer diameter of the cathode main body (7) is 12-20 mm, and the cathode main body (7) is made of tantalum tungsten.
  7. 7. An annular porous structured cathode for a magnetic plasma power thruster according to claim 1, characterized in that it comprises 7 outer air supply holes (4), the outer air supply holes (4) being uniformly distributed in the circumferential direction.
  8. 8. The annular porous structure cathode for the magnetic plasma power thruster of claim 1, wherein the cross section of the tail gas containing cavity (5) is circular, and the outer circular surface of the tail gas containing cavity (5) is parallel to the outer circular surface of the annular discharge cavity (8).
  9. 9. The cathode with the annular porous structure for the magnetic plasma power thruster of claim 1, wherein the inner side wall surface and the outer side wall surface of the inner ring emitter (2) and the outer ring emitter (1) are both used as electron emission surfaces.
  10. 10. The annular porous structure cathode for a magnetic plasma power thruster of claim 1, wherein the outer air supply holes (4) are tangent to the side wall surface of the circular groove of the outer ring emitter (1) and the outer side wall surface of the inner ring emitter (2), respectively.

Description

Annular porous structure cathode for magnetic plasma power thruster Technical Field The invention belongs to the technical field of electric propulsion power devices of space aircrafts, and particularly relates to an annular porous structure cathode for a magnetic plasma power thruster. Background With the development of spacecraft application electric propulsion platforms, various electric propulsion technology researches have been developed and great progress has been made, but the high-power space power supply technology is still in the development stage. MPDT belongs to one type of electric thruster, and is a device for converting electric energy into internal energy of neutral gas and then into directional kinetic energy. The advantage of MPDT over other types of electric thrusters is that a high specific impulse and a high thrust can be achieved simultaneously. The typical operating current of MPDT is typically on the order of hundred amperes. As an electron emission source, the cathode needs to bear electron emission of the whole thruster, and the cathode working environment of MPDT is extremely bad and is a bottleneck of the service life of the thruster. Disclosure of Invention The invention aims to provide an annular porous structure cathode for a magnetic plasma power thruster, which improves the effective current emission area of the cathode by more than 20% through the structural design of an inner ring emitter and an outer ring emitter, ensures the timely export of heat, reduces the occurrence of cathode partial burning phenomenon and improves the ignition stability. The above object of the present invention is mainly achieved by the following technical solutions: The annular porous structure cathode for the magnetic plasma power thruster is characterized by comprising a cathode main body, wherein the cathode main body comprises an inner ring emitter and an outer ring emitter, the outer ring emitter is a cylinder, one end of the outer ring emitter is provided with a circular groove, the inner ring emitter is annular, the inner ring emitter is arranged in the circular groove, a through hole is arranged on the circular groove, the inner through hole of the inner ring emitter is connected with the through hole to form an inner air supply hole, an annular discharge cavity is formed between the outer side surface of the inner ring emitter and the side wall surface of the circular groove of the outer ring emitter, and the annular discharge cavity and the inner air supply hole jointly form a cathode discharge channel; The circular groove is provided with a plurality of outer air supply holes, the other end of the outer ring emitter is provided with a tail air containing cavity, and the tail air containing cavity is communicated with the inner air supply holes and the outer air supply holes. And a gas damping pad is arranged in the tail gas containing cavity and used for damping the propellant flowing from one end of the tail gas containing cavity and balancing the distribution of the propellant among the inner air supply hole and the outer air supply hole. The central axes of the inner ring emitter and the outer ring emitter coincide. The depth of the annular discharge cavity is 30% -45% of the total length of the cathode main body. The ratio of the side wall surface area of the inner air supply hole to the total side wall surface area of the plurality of outer air supply holes is equal to the ratio of the inner ring side wall surface area of the inner ring emitter to the sum of the inner ring side wall surface area and the outer ring side wall surface area of the outer ring emitter. The outer diameter of the cathode main body is 12-20 mm, and the cathode main body is made of tantalum tungsten. Comprises 7 outer air supply holes which are uniformly distributed along the circumferential direction. The section of the tail gas containing cavity is circular, and the outer circular surface of the tail gas containing cavity is parallel to the outer circular surface of the annular discharge cavity. The inner and outer side wall surfaces of the inner ring emitter and the outer ring emitter are both used as electron emission surfaces. The outer air supply hole is tangent to the side wall surface of the circular groove of the outer ring emitter and the outer side wall surface of the inner ring emitter respectively. Compared with the prior art, the invention has at least the following beneficial effects: (1) The cathode structure designed in the invention can improve the effective current emission area of the cathode by more than 20 percent, and meanwhile, the homogeneous surface reduces the occurrence of cathode bias burning phenomenon. (2) The preferred coaxial porous annular discharge cavity design of the embodiment of the invention ensures that the heat deposited in the working process of the cathode is timely, uniformly and axially led out along the porous structure through the optimization of the depth acc