Numerical Simulation Of Rarefied Plasma Plume Flow Based On DSMC/PIC Method

The plasma plume flow exists widely in aerospace propulsion,industrial coating and nuclear reactor and other fields,such as plasma thruster in the aerospace electric propulsion system and micro cathode vacuum arc thruster in the micro satellite which is now being developed.The rarefied plasma plume,because of the size of the device is small,and the surrounding environment of vacuum degree is high,the flow field inside the particle number density is low,the rarefied gas flow effect is strong,the gas state is far from equilibrium,so the flow of plasma plume through ground experiment is difficult to study.Moreover,the traditional CFD method based on Navier-Stokes equation is no longer applicable due to the limitation of the continuum assumption in the rarefied plasma plume.Therefore,in the simulation of the plume field of rarefied plasma plume,the DSMC/PIC algorithm based on Boltzmann equation without continuous media assumption is needed to analyze and calculate.In this paper,the numerical simulation of rarefied plasma plume is carried out based on the DSMC/PIC hybrid algorithm,and the main contents are as follows:For the sparse neutral particle plume generated by the satellite attitude control thruster nozzle,there are both continuous flow area and thin and thin flow area in the flow process.Therefore,the CFD equation based on N-S equation and DSMC method are combined to solve the simulation process.Through numerical simulation,were obtained for force and torque of satellite and satellite solar array thin plume,and analyzes the different influence of different angles of the solar array plume effect on the satellite body and solar panel,while the impact of different weights and different grid numbers in the simulation of force and torque were the preliminary analysis,assessment of plume effects on satellite caused.For plasma devices working in rarefied plasma plume,numerical simulation is carried out to analyze the influence of wall interaction on plume.Therefore,the DSMC algorithm and PIC algorithm coupled DSMC/PIC hybrid algorithm is formed,adding the wall interaction module in the hybrid algorithm,the wall surface interaction,particle density and flow field of each component particle number density map changes with time,and it did not join the wall interaction diagram analysis thus,wall interaction effect on the plume.At the same time,in the thin plasma plume,the charged particle will produce an electric field that affects the motion of the particles in the plume.According to the three-dimensional unsteady rarefied plasma plume,adding electric field of PIC module based on unstructured grids in DSMC/PIC hybrid algorithm,analysis the influence of electric field on the plume,to obtain the electric field,flow field and particle number density of each component in the particle number density change with time,and it did not join the field map for comparative analysis,so as to obtain the effect of electric field on the plume.At the same time,the distribution of particle number in the initial ejection of the plume is analyzed,and the influence of the electric field on the particle motion distribution is obtained.