摘要

Hall effect thrusters (HETs) are efficient propulsion devices for the station-keeping of geostationary satellites. However, a further efficiency increase requires better knowledge of plasma and plasma-wall interactions. Electric probes are often used for diagnosing HET plasmas but the existing semi-analytical theories, used for the interpretation of probe characteristics, could only be applied with caution. Therefore, in this work a particle-in-cell model of the Langmuir probe immersed in plasma under conditions corresponding to those of HET plasma is developed. It was found that materials with a predominant elastic contribution to secondary electron emission (SEE) will generally lead to lower power deposition on a surface. In the case of inelastic and true SEE processes, the power deposited on a wall depends on the ratio of the sum of secondary electron energies to the electron impact energy. The axial magnetic field also leads to substantial reduction of power deposition on the probe.

  • 出版日期2014-5