Study On Electrostatic Adhesion Of Lunar Particle Based On DEM

In this thesis, electrostatic adhesion mechanism of lunar dust has been systematically studied. Lunar particle electrostatic adhesion is one of major issues faced by lunar-landing project. It will make the detector performance degradation and lifetime decay. Therefore, studying on electrostatic adhesion of lunar dust has important theoretical and practical significance.Charged lunar dust is fundamental reason of electrostatic adhesion. So lar radiation and solar wind plasma make lunar dust charge. Current category is analyzed, charged model of particle is setup according to single particle orbit theory and Maxwell energy distribution and charging mechanism is analyzed using MATLAB.Charged lunar dust has strong electrostatic adhesion. Based on electrostatic adhesion mechanism including constituent elements and their mathematical model, electrostatic adhesion mechanical model of spherical and irregular shape particle is established.Based on discrete element method, electrostatic adhesion of lunar dust is simulated using EDEM software. Firstly, electrostatic adhesion mechanism is verified by discrete element software and finite element software. Secondly, plugin of electrostatic adhesion is compiled using C++. At last, electrostatic adhesion is simulated to verify model accuracy and analyze effect of size and shape of lunar particle, electric field on lunar surface and material property of lunar probe on electrostatic adhesion.In addition, environment on lunar surface is strong radiation, high vacuum and extreme temperature. Charging characteristic and electrostatic adhesion of lunar dust is affected. Effect of environment on lunar surface on electrostatic adhesion is quantificationally analyzed. The most common UV and X-rays are chosen to study effect of solar radiation on electrostatic adhesion of lunar dust. The method of reducing the vacuum is used to research effect of high vacuum on electrostatic adhesion. Because relevant data of temperature on lunar surface is rarely and temperature of plasma varies with change of that on lunar surface. Therefore, method of temperature of plasma representing temperature on lunar surface is used to study effect of extreme temperature on electrostatic adhesion of lunar dust.