The Numerical Simulation On Electron Motion In Hypersonic Rarefied And Weakly Ionization Gas

When aircraft have the hypersonic flight mission with big Mach, the head ofaircraft will have intense interaction wieh flow field. At this point, the chemicalreaction and ionization reaction becomes an indispensable part of the simulation.Accompanied by it, the problem of electron motion in hypersonic rarefied andweakly ionization gas arises.The study of this problem is still in the developmentstage, all the method in the world now can not fully formed flawless solve on thisproblem.At present, DSMC (Direct Simulation Monte Carlo) is widely used inrarefied gas study and achieved satisfactory results. The main content of thisarticle is adding ionization reaction on the basis of the non-equilibrium chemicalreactions and processing the motion of electron after ionization. Due to the theelectronic quality singularity, it will moving much faster than other particles inthe case if we don’t have any treatment. This constitutes the technical difficultiesof DSMC within the same time step simulation of molecular motion, and makesdestruction of the electrically neutral assumption. In this paper, we use averagevelocity method to complete the simulation, it can basically meet the electricalneutral hypothesis, and also can avoid the physical properties’ singularity ofelectrons. Secondly, the nose of the aircraft’s aerodynamic parameters werecalculated, it is found that the maximum heat flux appear in the stagnation pointvicinity, and the region near the stagnation point is also strong in compressionand wall pressure maximum area.This paper has certain direct sense to f development and research of thehypersonic weakly ionization gas in rarefied, the analysis and simulation aboutthe motion of electron and aerodynamic parameters played a certain role in thepromotion and expansion of the DSMC method.