Hypervelocity Impact Experiment and Simulation for Ejecta

With more and more frequently increasing of human's space activities, ejecta produced by micrometeoroid and small space debris impacting on spacecraft surface will also further affect the space debris environment. The ground experiments and numerical simulations about aluminum sphere projectile hypervelocity impacting on 5A06 aluminum plate were carried out in this work. The mean value of the special ejecta parameters, such as the mean velocity of ejecta, the mean size of ejecta, the mean ejected angle of ejecta, were studied, setting up a foundation for constructing the space debris environment model for ejecta. In this paper, multiple regression method was used to obtain the relation among the mean velocity of ejecta, the impact velocity, and the size of the projectile. The results show that SPH (Smoothed Particle Hydrodynamics) can be effectively used in numerically simulating the mean velocity of ejecta, the mean size of ejecta and the mean ejected angle of ejecta; the mean velocity of ejecta increases with the impact velocity, and the size of the projectile; the ejecta in the process of material ejection can obey cone shape approximately, and the mean ejected angle is nearly 41 but basically unaffected by the impact velocity and the size of the projectile.