Design And Performance Research Of Orbital Control Thruster For Formation Micro-nano Satellites

The formation missions of micro-nano satellites put forward high requirements for the relative position maintenance and orbital maneuverability between the satellites.In view of the light weight,small size,and low power consumption of micro-nano satellites,it is urgent to develop a pulse-type orbit-controlled micro thruster with high specific impulse,micro thrust and fast response.In this paper,in response to the technical requirements of the "Tianyuan-1" micro-nano satellite formation flight mission,the overall design of the orbit-controlled thruster is carried out.The system mainly includes a first-level storage tank,a surge tank,solenoid valves,sensors,electric heating nozzles,and control circuits.By comparison,R134 a was finally selected as the propellant of the air-conditioning propulsion system.Then,based on the one-dimensional steady isentropic flow of ideal gas,the design of the nozzle was completed,and the fluid motion simulation analysis was carried out by using Fluent software.The results show that the temperature and pressure in the nozzle continue to decrease,and the exhaust velocity of the nozzle can reach twice the speed of sound,which is consistent with the characteristics of the Laval nozzle.Based on MEMS technology,the electrical heating nozzle has been processed and manufactured,and the heating performance of the heating wire has been tested.The heating wire can be heated to above 100°C within 30 s under the action of a pulsed power supply.In an approximate vacuum environment of 10 Pa,with nitrogen as the experimental gas,the performance of the thruster is tested using a torsion pendulum micro-thrust test bench.The results show that the thrust is proportional to the total pressure,and the actual thrust is about95% of the theoretical thrust;the specific impulse increases significantly with the increase of the temperature of the heating chamber.When the temperature of the outer surface of the glass sheet is 95℃,the specific impulse increases by about 10%,and the actual specific impulse is about 65% of the theoretical specific impulse.Converted into R134 a propellant,when the total pressure is 0.06 MPa,the thrust is 4.6m N;when the temperature of the outer surface of the glass sheet is 95℃,the specific impulse is 55 s,which can meet the mission requirements of orbitcontrolled thruster.