CN-122021460-A - Ion thruster anode assembly integrated structure design optimization method based on additive manufacturing

CN122021460ACN 122021460 ACN122021460 ACN 122021460ACN-122021460-A

Abstract

The invention relates to the technical field of aerospace electric propulsion, in particular to an integrated structural design optimization method of an anode assembly of an ion thruster based on additive manufacturing, which comprises the steps of determining the outer size of a gas distribution ring of a discharge chamber by combining input parameters of the discharge chamber of the ion thruster; the method comprises the steps of calculating circumferential pressure distribution of a gas distribution ring, completing aperture number and gradual change aperture size design by combining the pressure distribution and the aperture matching of the gas distribution ring, designing a bidirectional spiral pressurizing flow channel, combining CFD gas uniformity simulation analysis, and finally integrally modeling, designing and forming the anode of the pressure gradient compensation type ion thruster and the gas distribution ring based on additive manufacturing. Aiming at the core requirement of the uniformity of circumferential gas supply of the ion thruster discharge chamber, the invention realizes the uniform distribution of gas by the pressure compensation of the flow channel and the reverse adjustment of the gradual aperture, overcomes the problem of uneven circumferential gas supply of the traditional gas distribution ring caused by the pressure gradient of the flow channel, and realizes the uniform gas supply of the ion thruster discharge chamber.

Inventors

LI JIANPENG
WEI LIEJIANG
LI WENFENG
SUN XINFENG
JIA YANHUI
ZHANG XINGMIN
SHI YOUCHENG
CAO WENBIN
ZHAN PENG

Assignees

兰州理工大学

Dates

Publication Date: 20260512
Application Date: 20260403

Claims (7)

1. The ion thruster anode assembly integrated structure design optimization method based on additive manufacturing is characterized by comprising the following steps of: s1, determining the outer dimension of a gas distribution ring of a discharge chamber according to input parameters of the discharge chamber of the ion thruster; S2, carrying out circumferential pressure field modeling of an annular orbit of the gas distribution ring by adopting a one-dimensional annular runner pressure attenuation model, calculating circumferential pressure distribution of the gas distribution ring, and simultaneously calculating the flow of an air outlet orifice of the gas distribution ring by adopting a modified poise page equation according to the characteristic that the gas flow is in a sliding flow area under the vacuum environment of the ion thruster; Step S3, combining pressure distribution and gas distribution ring aperture matching to finish aperture number and gradual change aperture size design; S4, designing a bidirectional spiral pressurizing flow channel, arranging 2 air inlets, and integrally designing two correspondingly connected spiral pressurizing flow channels with an anode along the anode wall surface of the ion thruster, wherein the two spiral pressurizing flow channels are spirally lifted clockwise and are connected with the opposite corners of the gas distribution ring, and the sectional areas of the spiral pressurizing flow channels shrink exponentially to supplement pressure attenuation; s5, carrying out gas uniformity simulation analysis on the integrated structure of the anode and the gas distribution ring of the pressure gradient compensation type ion thruster by combining CFD, and completing structure optimization through iterative verification; And S6, carrying out integrated modeling design on the optimized anode and the gas distribution ring of the pressure gradient compensation type ion thruster, and completing forming processing based on an additive manufacturing technology.
2. The method according to claim 1, wherein in the step S2, the calculation model of the circumferential pressure distribution of the gas distribution ring is: ; Wherein P1 is the pressure of an air inlet at the joint of the air inlet pipe and the gas distribution ring, D 1 is the annular diameter of the gas distribution ring, h is the diameter of a flow passage of the gas distribution ring, K is the Knudsen number, mu is the aerodynamic viscosity, and Q is the flow rate of an air outlet orifice of the gas distribution ring; The modified poispage equation is: ; Where d is the exit aperture, P i is the orifice upstream pressure, P d is the ion thruster discharge chamber pressure, L is the effective length of the gas outlet hole flow passage of the gas distribution ring.
3. The method for optimizing the integrated structural design of the anode assembly of the ion thruster based on additive manufacturing according to claim 2, wherein the step S3 specifically comprises: the diameter distribution of the gradual change gas outlet hole of the pressure compensation of the gas distribution ring is obtained by a simultaneous flow equation: ; ; wherein Q1 is the total input flow, N is the number of gas distribution ring pressure compensation gradual change gas outlet holes, and Q avg is the average flow of single gas outlet holes; the simplification is obtained: ; Wherein d b is the reference design aperture, and d i is the aperture of the ith air outlet.
4. The method for optimizing the integrated structural design of an ion thruster anode assembly based on additive manufacturing according to claim 3, wherein the step S4 specifically comprises: the pressure decay is supplemented by the shrinkage of the flow passage sectional area, the spiral pressurizing flow passage sectional area is exponentially shrunk, and the sectional area A (y) along the flow passage direction at the distance y is: ; Wherein A 0 is the initial sectional area of the flow channel, and k is the contraction coefficient; The method of calculating the shrinkage factor k is as follows: ; Wherein P ref is the pressure at the inlet.
5. The method according to claim 1, wherein in step S3, the pore size is gradually increased from the proximal end to the distal end and is maximized at the farthest end from the gas inlet, in combination with the pressure distribution and the gas distribution ring pore size matching to complete the pore size number and the gradual pore size design.
6. The method according to claim 5, wherein in the step S3, a triangular micro-rib structure is provided in the inner flow channel of the gas distribution ring, and a periodic velocity gradient is formed by dividing the flow channel by the triangular micro-ribs, so as to induce local vortex and enhance gas mixing.
7. The method according to claim 1, wherein in the step S6, the gas distribution ring outlet hole is tapered and gradually decreases from the outside to the inside based on the integrated modeling design and forming process of the pressure gradient compensation type ion thruster anode and the gas distribution ring.

Description

Ion thruster anode assembly integrated structure design optimization method based on additive manufacturing Technical Field The invention relates to the technical field of aerospace electric propulsion, in particular to an integrated structural design optimization method of an anode assembly of an ion thruster based on additive manufacturing. Background Electric propulsion is a sign of an advanced satellite platform due to the advantages of high specific impact, long service life and the like, power is provided for a spacecraft, and in the field of interstellar deep space exploration, an electric thruster is widely valued in various countries and is applied to engineering, and the ion thruster generates thrust by ionizing a gas working medium into plasma and accelerating leading-out ions. The existing ion thruster gas distribution ring has the defects that the pressure at the near end is high and the pressure at the far end is low because of the position of an air inlet pipe, so that the air inflow is different, the pressure at the end of the air inlet pipe is concentrated, the flow difference between the near end and the far end is caused, the discharge of the thruster is caused to be uneven, the current density of an ion beam is even and poor, the sputter etching of the ion thruster is aggravated, and the stable discharge and the service life expansion of the thruster are restricted. And part of the design adopts equal-aperture uniformly distributed open pores or simple linear gradual change apertures, does not consider the dynamic pressure attenuation rule in the flow channel, is limited by the manufacturing process, and cannot realize the integrated forming and manufacturing of the micrometer gradual change apertures and the complex inner flow channel by traditional mechanical processing. Therefore, the integrated structure and the design method of the anode component of the ion thruster based on additive manufacturing are provided, the problem of uneven circumferential air supply of the traditional gas distribution ring caused by the pressure gradient of the runner is solved, and meanwhile, the integrated design and the manufacture of the anode, the complex inner runner and the gradual change hole gas distribution ring are realized based on additive manufacturing. Disclosure of Invention The invention aims to provide an integrated structural design optimization method of an anode assembly of an ion thruster based on additive manufacturing, aiming at the core requirement of circumferential gas supply uniformity of a discharge chamber of the ion thruster, gas is uniformly distributed through channel pressure compensation and gradual aperture reverse regulation, the problem of uneven circumferential gas supply caused by channel pressure gradient of a traditional gas distribution ring is solved, meanwhile, the integrated design and manufacture of an anode, a complex inner channel and a gradual aperture gas distribution ring are realized based on additive manufacturing, and finally, uniform gas supply in the discharge chamber of the ion thruster is realized. The aim of the invention can be achieved by the following technical scheme: An ion thruster anode assembly integrated structure design optimization method based on additive manufacturing comprises the following steps: Step S1, determining the outer size of a gas distribution ring of a discharge chamber by combining the structure, the size, the gas supply mode and the working medium input parameters of the discharge chamber of the ion thruster; And S2, calculating circumferential pressure distribution of the gas distribution ring, and carrying out circumferential pressure field modeling of the annular track of the gas distribution ring by adopting a one-dimensional annular flow passage pressure decay model. The pressure distribution is: ; Where P1 is the pressure of the inlet at the junction of the inlet tube and the gas distribution ring, D 1 is the annular diameter of the gas distribution ring, h is the diameter of the gas distribution ring flow channel, K is the Knudsen number, μ is the aerodynamic viscosity, and Q is the gas distribution ring outlet orifice flow. And according to the gas flow characteristic of the ion thruster in the vacuum environment, the gas flow is in a sliding flow area, and the flow of the gas outlet orifice of the gas distribution ring of the ion thruster is calculated by adopting a modified poispage equation. ; Where d is the exit aperture, P i is the orifice upstream pressure, P d is the ion thruster discharge chamber pressure,L is the effective length of the gas outlet hole flow passage of the gas distribution ring. Step S3, combining pressure distribution and gas distribution ring pore diameter matching to complete the design of the pore diameter number and gradual change pore diameter, and obtaining the gas distribution ring pressure compensation gradual change gas outlet pore diameter distribution by a simultaneous flow