東華大學圖書館 |

Language: English

Help

回圖書館首頁

手機版館藏查詢

Back

Switch To: Labeled | MARC Mode | ISBD

Current Transport and Onset-Related ...

Moeller, Robert Carlos.

Linked to FindBook

Google Book

Amazon

博客來

Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields.

Record Type:	Language materials, printed : Monograph/item
Title/Author:	Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields./
Author:	Moeller, Robert Carlos.
Description:	214 p.
Notes:	Source: Dissertation Abstracts International, Volume: 74-06(E), Section: B.
Contained By:	Dissertation Abstracts International74-06B(E).
Subject:	Engineering, Mechanical. -
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3554035
ISBN:	9781267938411

Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields.
Moeller, Robert Carlos.

Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields. - 214 p.

Source: Dissertation Abstracts International, Volume: 74-06(E), Section: B.

Thesis (Ph.D.)--California Institute of Technology, 2013.

This work investigated the effects of tailored, externally-applied magnetic fields on current transport and near-anode processes in the plasma discharge of a magnetoplasmadynamic thruster (MPDT). Electrical and plasma diagnostics were used to determine whether applied magnetic fields could mitigate the effects of the "onset" phenomena, including large-amplitude terminal voltage fluctuations and high anode fall voltages associated with unstable operation and anode erosion. A new MPDT was developed and operated with quasi-steady 1 ms pulses from 36 kW to 3.3 MW with argon propellant. Three magnetic configurations studied included self-field operation (without external electromagnets) and two applied poloidal magnetic fields. One configuration used magnetic field lines tangential to the anode lip (and intersecting the anode further upstream) and the other created a magnetic cusp intersecting the anode downstream.

ISBN: 9781267938411Subjects--Topical Terms:

783786
Engineering, Mechanical.

Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields.
LDR:03434nam 2200301 4500 001 1958092
005 20140224122713.5
008 150212s2013 ||||||||||||||||| ||eng d
020 $a 9781267938411
035 $a (MiAaPQ)AAI3554035
035 $a AAI3554035
040 $a MiAaPQ $c MiAaPQ
100 1 $a Moeller, Robert Carlos. $3 2093075
245 1 0 $a Current Transport and Onset-Related Phenomena in an MPD Thruster Modified by Applied Magnetic Fields.
300 $a 214 p.
500 $a Source: Dissertation Abstracts International, Volume: 74-06(E), Section: B.
500 $a Advisers: Joseph E. Shepherd; James E. Polk.
502 $a Thesis (Ph.D.)--California Institute of Technology, 2013.
520 $a This work investigated the effects of tailored, externally-applied magnetic fields on current transport and near-anode processes in the plasma discharge of a magnetoplasmadynamic thruster (MPDT). Electrical and plasma diagnostics were used to determine whether applied magnetic fields could mitigate the effects of the "onset" phenomena, including large-amplitude terminal voltage fluctuations and high anode fall voltages associated with unstable operation and anode erosion. A new MPDT was developed and operated with quasi-steady 1 ms pulses from 36 kW to 3.3 MW with argon propellant. Three magnetic configurations studied included self-field operation (without external electromagnets) and two applied poloidal magnetic fields. One configuration used magnetic field lines tangential to the anode lip (and intersecting the anode further upstream) and the other created a magnetic cusp intersecting the anode downstream.
520 $a The influence of the applied fields on the discharge current streamlines, current densities, and key plasma properties (electron temperature, number density, and plasma potential) was studied. Key findings included that the current pattern and current densities redistributed to follow the applied magnetic field lines. Also, the anode fall voltage was substantially reduced with both applied fields over a large range of currents (and eliminated at 8 kA). These results occurred because applied magnetic field lines intersecting the anode provided a high conductivity path and reduced the local electric field required to sustain the radial current densities. The applied fields reduced the amplitude and frequency of the terminal voltage fluctuations (up to 49%) over a broad range of currents and also decreased transients in the ion saturation current, which suggest reduction of current filamentation and surface-eroding anode spots. Additionally, the cusp field reduced mean terminal voltages over the entire range of discharge currents (up to 31%), and the tangential field lowered terminal voltages below 10.7 kA. These significant reductions in onset-related behaviors should lead to improved thruster lifetime and increased efficiency. These results suggest a distinctive and more effective approach to influencing the near-anode phenomena and mitigating the effects of onset with appropriately designed applied magnetic fields that differ from those used in the vast majority of conventional, so-called "applied-field MPD thrusters.".
590 $a School code: 0037.
650 4 $a Engineering, Mechanical. $3 783786
650 4 $a Engineering, Aerospace. $3 1018395
650 4 $a Physics, Fluid and Plasma. $3 1018402
690 $a 0548
690 $a 0538
690 $a 0759
710 2 $a California Institute of Technology. $b Mechanical Engineering. $3 2093076
773 0 $t Dissertation Abstracts International $g 74-06B(E).
790 $a 0037
791 $a Ph.D.
792 $a 2013
793 $a English
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3554035