Simulation Study on Discharge Characteristics of Radio Frequency Ion Thruster with Iodine Working Medium
Iodine,as a potential working medium in space thrusters,has attracted much attention in recent years.Unlike xenon,the discharge products of iodine working medium are more complex,containing small amounts of I-,I2+,I2+and I3+.Although the content of polyvalent ions is small,it has a great influence on the working performance of thrusters.In this paper,a two-dimensional axisymmetric model is established based on plasma discharge,studying the effects of mass flow rate,RF power and background pressure on two main ionization products,I+and I2+.When the mass flow rate ranges from 20 to 70 mL/min,I+slightly decreases and I2+slightly increases with the increase of mass flow rate.When the RF power ranges from 100 to 650 W,I+increases rapidly with the increase of RF power,and I2+decreases slightly.When the background pressure ranges from 0.001 to 0.1 Torr,I+initially increases rapidly with the increase of background pressure and it begins to decrease at around p0=0.015 Torr.I2+has maintained a slow increase.Ignoring the influence of ionization loss,conducting a full factor design of experiment(DOE)of the three influencing factors.When the mass flow rate is 60 mL/min,the RF power is 150 W,and the background pressure is 0.015 Torr,obtaining the optimal product I2+∶I+=0.204094,which is consistent with the simulation result I2+∶I+=0.205069,and the error is 0.48％.
Radio-frequency ion thrustersDOEIodine working mediumICP
万方数据
维普
