Open AccessFeatures of electron-wall collision frequency with saturated sheath in Hall thruster
Author(s) -
Fengkui Zhang,
Yongjie Ding
Publication year - 2011
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.60.065203
Subject(s) - collision frequency , collision , electron , atomic physics , backflow , physics , materials science , nuclear physics , mechanical engineering , computer security , computer science , engineering , inlet
In the paper we study the electron-wall collision frequency in Hall thruster using the two-dimensional particle-in-cell method. It is found that electron-wall collision frequency is greatly increased in the state of saturated sheath compared with in the state of classic sheath, and even two orders of magnitude higher. Thus, the contribution of electron-wall collision frequency in the state of saturated sheath to near-wall current will be non-ignorable. In this paper the reason why the electron-wall collision frequency is increased in the state of saturated sheath is further analysed. It is believed that the increase of electron-wall collision frequency is caused by rather low sheath potential drop and the backflow of secondary electron emitted from the wall.