ЗОНДОВІ ТА СПЕКТРАЛЬНІ ДОСЛІДЖЕННЯ МАЛОПОТУЖНОГО ЕЛЕКТРОРЕАКТИВНОГО ХОЛЛОВСЬКОГО ДВИГУНА

Abstract

The work is devoted to the study of a low-power Hall Effect Thruster. The currency of developing and increasing of integral characteristics of Hall Effect Thruster with power consumption less 0,3 kW is substantiated. The main directions of low-power Hall Effect Thruster investigation are considered. The analysis of latest investigations and studies of low-power Hall Effect Thruster showed the existence of three main directions - development of fundamentally new schemes, improvement of existing models, as well as works on study of physical processes features in Hall Effect Thruster with power consumption up to 0,3 kW.Using developed Hall Effect Thruster ITM-31, distribution of plasma parameters in the discharge channel has been studied by probe diagnostic, and the wear of the discharge chamber walls has been studied by optical spectroscopy. Thruster characteristics are given. Investigations were carried out in a vacuum chamber 0,5 m in diameter and 0,8 m in length. The pumping was carried out by a diffusion pumps. At a maximum xenon consumption rate 1,5 mg/s, the working pressure in the vacuum chamber did not exceed 2∙10-3 Torr. Probe measurements were performed using a single probe; probe was inserted into the discharge channel from the anode side. Calculation of plasma parameters was carried out graphically. The temperature and concentration of charged particles are calculated, and the electric potential distribution is obtained. Conclusions are made about the properties of the accelerating layer.It is shown that one of the non-intrusive methods of diagnostics is the method of optical emission spectroscopy (OES). With the help of this method it is possible to provide plasma parameters investigation and characteristics of the construction wear during the thruster testing at different regimes of operation and on each stage of thruster lifetime. For the spectroscopic investigation of the Hall Effect Thruster discharge chamber walls wear the scheme of the experiment and the equipment description is presented. For the estimation of the discharge chamber insulators erosion rate the spectral lines criteria and method of wavelengths selection is presented. Mathematical model of the thruster plasma plume experimental emission spectral data processing is described that was developed on the basis of actinometry hypothesis and corona model. Results of the spectroscopic investigation of the discharge chamber erosion rate at different thruster operational regimes are presented. From experimental and theoretical model the dependence of the discharge chamber insulators erosion rate from the discharge voltage was processed.