Effect of Magnetic Mirror on the Asymmetry of the Radial Profile of Near-Wall Conductivity in Hall Thrusters

2009 ◽  
Vol 11 (3) ◽  
pp. 1-7
Author(s):  
Yu Daren ◽  
Liu Hui ◽  
Fu Haiyang
2008 ◽  
Vol 48 (8) ◽  
pp. 543-554 ◽  
Author(s):  
D. Yu ◽  
H. Liu ◽  
Y. Cao ◽  
H. Fu

2010 ◽  
Vol 29-32 ◽  
pp. 519-524
Author(s):  
Zhi Wen Wu ◽  
Shu Shu ◽  
Da Ren Yu ◽  
Xiang Yang Liu ◽  
Ning Fei Wang

The wall material plays an important role for the electron current due to near wall conductivity in Hall Thrusters. A Monte Carlo method combined with a one dimensional steady sheath model is presented and is applied to simulate the electron conductive current due to near wall conductivity for the different channel wall materials of Hall thruster. The simulation results show that the higher the secondary electron emission (SEE) coefficient of the channel wall material is, the greater the electron conductive current is. Based on the simulation, a physical explanation is given from the viewpoint of near wall conductivity. For the channel wall material with low SEE coefficient, the secondary electrons taking part in the near wall conductivity becomes less. In addition, the absolute potential drop in the sheath near the wall increases, which means that the sheath can stop more electrons from colliding with the channel wall. And consequently the electron conductive current due to near wall conductivity is much less. The situation is vice verse for the channel wall material with high SEE coefficient. The simulation results are qualitatively in accordance with the experiments. The results can help to choose and design the wall material of the Hall Thrusters with a high performance.


2007 ◽  
Vol 14 (6) ◽  
pp. 064505 ◽  
Author(s):  
Daren Yu ◽  
Hong Li ◽  
Zhiwen Wu ◽  
Wei Mao

Author(s):  
Serge Barral ◽  
Karol Makowski ◽  
Zbigniew Peradzynski ◽  
Michel Dudeck
Keyword(s):  

Author(s):  
Zhen Qian ◽  
Minghui Zhang ◽  
Hao Yu ◽  
Fei Wei

Radial profiles of particle velocity in a large scale (418 mm I.D.) downward Circulating Fluidized Bed (CFB downer) were obtained via a Laser Doppler Velocimetry (LDV) system. Results show that particle velocity is gradually increasing along the radial direction and there exists a peak value in the near wall region. Such unique radial profile shape can be explained by the solids accumulating trend in the near wall region of the downer. Experiment results in this large scale downer are also compared with those obtained by other researchers in small scale units so as to investigate the scale-up effect on the radial particle velocity distribution in the downer.


Sign in / Sign up

Export Citation Format

Share Document