Research On Three Dimensional Full Particle Numerical Simulation Of Plume

Electric propulsion(EP)is increasingly being applied to satellite communication and deep space exploration.The influence of EP plume on spacecraft becomes an important problem which restricts the further application of electric propulsion.In practical applications,the EP plume will do great harm to spacecraft,and even lead to spacecraft failure.Therefore,how to reduce or avoid the influence of EP plume on spacecraft is essential for the future application of EP.The experimental study and numerical simulation method are used in the study of electric propulsion plume.However,the experiment is time-consuming and expensive,and cannot get a macro understanding of the distribution of plume.The numerical simulation is widely used because of it is economic and well-adapted,and can get a more comprehensive understanding of the distribution of plume.The composition of the electric propulsion plume consists of beam ion,neutral atom,charge exchange(CEX)ion.Characteristics of ion thruster plume–spacecraft interactions are primarily determined by the CEX ion.Therefore,CEX ion is the main research object of simulation of EP plume.The distribution of CEX ions in the plume is determined by the distribution of the beam ions and neutral atoms.Therefore,how to accurately simulate the distribution of beam ions and neutral atoms is the primary problem of numerical simulation.At present,common simulation models include analytic model and full particle model.The analytical model is fast in calculation and agrees well with the experimental results.But the analytical model is only proposed for the plume of ion thruster,and its versatility is poor.The simulation results are very sensitive to the initial parameters,so the initial parameters setting of the analytic model is discussed.Analytic model can only apply to the case where the divergence angle is far less than 1 radian.Moreover,the analytical model is not applicable to the plume of annular ion thruster developed in recent years.The full particle model has better versatility,and can also be used to deal with plume fields with complex boundaries,but most of the current particle models are two-dimensional axisymmetric model and the accuracy of the simulation resultsis also not verified.Therefore,based on the existing full particle model,a 3D full particle model is proposed.It consist of Particle model for the ion beam,DSMC model for the neutral atoms and IFE-PIC-MCC model for CEX ions.On the basis of this,the 3D full particle model is used to analyze the effects of bias multi thruster CEX ions on spacecraft.By comparing the three-dimensional particle model simulation results and the analytical model with experimental data to verify the correctness of the simulation results;its versatility was verified through the simulation of the plume of annular ion thruster;based on bias multi thruster plume,and the analysis of the Mo CEX ion,the superior working condition of the satellite was predicted,and the protection measures of solar panels are given.